Disgruntled sixfivediesel owners

[grancito]

I see posts of some that are sick of the problems with their 6.5, but from looking at all of the posts, it is not a diesel problem, mostly it is electrical, and so would be the same if one had a gasoline engine, and probably worse because they have more sensors. Don't give up on your diesel.

[RipnRun]

I love my truck. It's diesel prices that get me pissed off. Right now I'm paying around 90 cent per gallon more than regular unleaded.

[Shlep]

Only thing that's got me pissed at my 6.5 is it's lack of power towing large loads, as a matter of fact even after the purchase of it's replacement I decided to keep it anyway because of it's reliablity :D

[trukdoc]

...15...4by is14...show me a 14-15yr old dodgem or ford thats holding togather good as my jimmys...diesel technology is in a constant state of flux{for you aggies that means it changes a lot}...a 4.3 z motor{gasser}putz ot the equivalent hp as a mid 70s 350...1st 6.9s{original diesel for ford p/u} were 145hp...in 79 that engine was used by IH in 70 passenger skool buses...most complaints about towing power I get are really about towing speed...cause you alwayz got that one buddy that runz off and leaves you...6.5 is good solid power..only real problem is gmz tstat hsg design...still simple engine{mech pump eng.}simple to troublshoot,,simple to repair...there are some very smart people on this site and ANY problem can be solved with patience...and perserverence...

[JD_countryboy]

Gms 4.3l Z gas engine is really stout. Add some edelbrock performance parts and bore it fourty over, you got a realy great powrful fuel efficant engine that can power lots. Loved the one in my 91 s-10 when i had it. THat 4x4 s-10 with 5 speed manual would kick some @ass. beat alot of stuff with it. s-10 has terminal ohio cancer and is sittin in the barn, just aint decided what to build to drop the whole injected 4.3 into. 18 mpg in town, 22 on the highway. Wont handel what i pull with my 6.5 though. Ran the crap outta it and it takes it. Looked up thye engine hp specs once, stock had more hp than most all small v-8 of that time frame. (any manufature) Torque was cpomparable, but usually a touch less. But i could outrun stock v-8 dakotas. and repowered rangers with 302 in them. Man that pissed them off :D of course, i've outrun quite a few vehicles with my 6.5 too. man does that turn heads

[hraney]

most of the folks around here I hear complain about the 6.5TD stepped out of 454 Chevies or 460 Fords and expected the diesel to have the same "snap" as their gassers. Needless to say they were disappointed.
But.... show me a 454 or 460 that would stay together like the 6.5TD (with maintenance) and get the fuel mileage of the 6.5TD.
And as far as diesel prices, my K3500 crew cab is still cheaper to operate than my wife's 04 Honda Pilot and she gets nearly twice the mileage on cheaper fuel. Of course, it took making her get out the payment books and insurance papers to prove that to her.

[deerefanatic]

I don't know. My neighbor has a 454 Vortec powered GMC that's holding together nicely, and gets the same mileage as my 6.5 when unloaded and about 2 mpg less when loaded..... And his starts every morning which is alot more than I can say about my 6.5........

Oh, and I got to drive it hauling a 32' gooseneck stock trailer (steel, not aluminum) that weighs so much, it will put my half ton down on the bump stops.... VERY HEAVY..... It ran circles around my 6.5 pulling half to a third as much......

[Oldsmoke]

So I been lookin' back over a couple old Diesel Power's and in a write up on the Stanadyne DB2 it says the pump supports motors with as high as 200 HP.

I would assume that unless the displacement of the pump is enlarged there is no way you can get more than 200 crankshaft hp from the pump since it simply can not pump enough fuel.

It has been my understanding that the only difference between a DB2 and a DB4 is that the DB4 is electronically controlled and the DB2 is mechanical.

So is there no way to get more that 200hp from our 6.5's?

[grancito]

I think that diesel power is wrong, because theoretically my burb is producing more than 200 hp with a #9 resistor.

[Oldsmoke]

Well, supposedly the article was written by a Stanadyne engineer.

[grancito]

There must have been a printing error, because they can be chipped to 300 hp.

[Buddy]

And regardless of the fuel input you can add propane and push a lot more power that doesnt require additional diesel fuel.

[Stumped]

I had 11,000lbs(or so) behind mine this week.Even with 3:42s and a zillion miles,the old 6.5 amazes me.I dont tow a lot,but couldnt see how you would need much more than our trucks make stock.Granted the bobcat doesnt sit as high or as blunt as a camper ect,but really felt strong to me.My 454 1 ton couldnt hold a candle to the 6.5 loaded with same weight

[Oldsmoke]

Didn't mean to burst anybody's bubble or anything but I did find that article a little disturbing. I am very happy with the power my truck puts out and I do feel it will pull at least as much as a big block gasser.

[JD_countryboy]

my seat of the pants opionion. My 6.5 TD will pull the same and just as good as a 99 f350 7.3 joke. Was lucky enough to hook to the same trailer/ load once with the work truck and my truck. THe better part, my 6.5 started rollin away with the trailer soon as foot off brake. THe joke, you gotta give it fuel to make enough power to start movin and doesn't amke any power till the turbo spools up. Plus i like my truck alot more than any ford.

[Stumped]

We took brothers powerstroke on a 6x6 retrieval.Ran well,18 mpg(with a utility bed,not aerodynamic) but listening to that loud motor made me like the old 6.5 even mmore,plus 3 more mpg.

[Husker 6.5]

So I been lookin' back over a couple old Diesel Power's and in a write up on the Stanadyne DB2 it says the pump supports motors with as high as 200 HP.

I would assume that unless the displacement of the pump is enlarged there is no way you can get more than 200 crankshaft hp from the pump since it simply can not pump enough fuel.

It has been my understanding that the only difference between a DB2 and a DB4 is that the DB4 is electronically controlled and the DB2 is mechanical.

So is there no way to get more that 200hp from our 6.5's?

Recheck your math. The article said the DB2 can support up to 50hp per cyl = 400hp. With marine injectors, intake and exhaust mods, boost increase to 15 psi., and the IP turned all the way up, you can make a reliable 300-320 hp from a DB2 without major engine or IP mods. If you want more power, the DB2 can be modified to acheive the 50hp level, but the 6.5 won't handle that hp/torque level very long without extensive ($) modifications to the motor, and you will lose low rpm drivability.

Husker 6.5

[Oldsmoke]

I wish you were right on that Husker. Get out those reading glasses!

[Stumped]

Id like to throw an HX35 thats in my stash(non w/gated ) and my 4911 pump on the old 6.5 and see what really happens.Crank up the fuel rate bout a 1/2 turn with a tad adv on the timing and tune with the pyro from there.I bet you could get 275 horse w/o a cooler or meth/water.But after the rocker arm,valve spring fiasco,and then using the WRONG hole to reinstall the i/p,i swore i would never pull it apart again.The HX looks like the same pattern as our GM turbos,and the discharge even looks like its clocked right and spaced to hook it up factory looking.Next time I do a turbo on it,the inner fenders coming out

[Oldsmoke]

Is the 4911 pump an American Bosch? I'm thinking that might be what's on an old DT 466 IH I have laying around. Looks like the DB2 only a little bigger?

[Stumped]

I believe the 4911 just has a diff calibration.I kmow the part throttle timing cam is different profile(I changed the 6.2 cam out for the 6.5) and something about the tranfer pmp piston diameter(a few mm) but phys are the same size I believe.The pmp I have is a Stanadyne DB 2 4911 J code application 1992-3 6.5 turbo VIN F no emissions

[Husker 6.5]

I wish you were right on that Husker. Get out those reading glasses!

You're right, I'm wrong. Got my new reading glasses, too! I hate having all this stuff floating around in my mind, these over 40 moments drive me nuts, and 50 is around the corner! Yet, I have personal knowledge of DB2 6.5's that are putting down 230-240 hp at the rear wheels on a dyno, which means they're running about 260-70 hp at the crank. DB2's have been turned up, no other pump mods, marine injectors, intake, 4" exhaust. With rotor and housing mods they will support 400 hp (but the 6.5 motor may not, fatal bottom end/headbolt failure).

[Stumped]

Do you know which pump works best if you were shooting for those h/power #s? I have a decent collection,but most are 2829 and 1 good 4911,1 worn 4911.

[Husker 6.5]

4911 for 92-93 6.5T. Just turning the screw in and tuning via EGT with adding marine injectors should get you another 40 hp easily, with intake and exhaust, further tuning will get you to about 80 hp. A competent diesel shop (preferably Stanadyne approved repair) with an experienced Stanadyne/Roostamaster tech should be able to mod your IP. Essentially, by increasing the transfer volume, you then increase the volume and duration of the injection pulse - thus more hp.

Doug (Sixnickel) is really good with the mechanical pumps, he has a lot of years experience with them. PM him for further assistance.

Husker 6.5

[Stumped]

Personally,I think the bad rap is good for us.I can get a whole truck for what a used motor of the other brands sell for.I would bet 90% of the i/ps replaced are good.For some unknown reason,the 2nd battery seems neglected(clean terminals ect) so the same goes for bad starters.The OPS IS the main failure point on the engine support end.If there are any fuel leaks after the lift,bad ops makes system pull air(ie i/p pulls fuel instead of having it pushed to it) then timing adv all the way.Then the main webbing in the block gives due to increased cyl pressure and the timing event being off.Just cause she wasnt leaking fuel out doesnt mean anything.Air molecules are smaller than fuel,air can get in where fuel couldnt get out.I deal with it daily at work.Our equip test for 5 diff gasses.A small air leak sometimes will let the smaller moleculed c1-3 gasses leak right out,while holding the larger c 4-5 molecules trapped inside test column.I am off to rescue yet another truck today with rotted fuel system and brake lines.$800 for the truck with 92,000 miles and a nice brown interior.That 454 is outta there.

[sixnickel]

Like I have said before.If you know them 6.2/6.5s you got to love them. But if you don't know them and nobody around ya does ether, I guess you got to hate them. Our gain !!!

[deerefanatic]

I know there's alot of guys that like 6.5's, and I'll agree it isn't the worst, but if I had a truck with a 454, it'd stay... Our neighbor's 454 Vortec would run circles around my 6.5 and doesn't really consume much more fuel than my 6.5 under a similar load.....

[Stumped]

Its a 95 1 ton HD 3500 2wd straight axle with the NV4500.It the new gen 454 and wont get out of its own way.It does get decent mileage(bout 14-15 out on the road) with the mesh Tommy Lift gate and the cattle racks.Honestly,if you let the gate down on the chains(not up)its like night and day on power.I never was happy with the way the gears are spaced in that NV either.The 2-3 spread is annoying at best.I thought if I found a 92-93 cluster and harness and pull the electronic pump off I could stick that 6.5 in.The last one I got has really bad rust on the motor and pulleys ect and didnt want to use it.This one didnt sit as long.Im not starting it until I change the oil and fuel filter.We towed her home today.I cant EVER get a GM8,always 3-5s.

[Stumped]

By the way,you ever fooled with the vacume pump(put the o-ring kit in) on that Mercedes 300?I have one sitting at my brothers house with the vac system out.I would love to get it going,but it made it to the back burner.Has a killer 5 cyl turbo diesel.Its keeping the trans from shifting properly,so we left it parked.

[JD_countryboy]

For the most part, that swhy anything gets a bad rap. the guys running it, just dont know how to operatit it properly, and surely donmt know how to fix and or maintain. Im lovin my 6.5 more evertime i drive it. Pissed me off a bit earlier today when the started suddenly just up and quit. Had it towd 40 miles back home. New starter and it spins over faster then ever now. So maybe the old one was wore, and heaed out anyway, just didnt know it. Even stupider thing, Had it tested, while on the tester, rattled like a cummins, and thoughth it was gonna pop. Passed the test though. No way in the world woulfd i have ever put it back in.

On a different note, the IH rollback that hauled us home just randomly died on us once, and when we hopped out to unload my truck, noticed a front wheel lug nut layin on the ground by the tire. The rollback had new front tires installed in the last few days( so i was told tires still had tits on them) Looked to me like tire place cut a lugnut off cut into the sud and just put a new nut on the damaged stud anyway. What a day.

[tdijetta99]

Its a 95 1 ton HD 3500 2wd straight axle with the NV4500.It the new gen 454 and wont get out of its own way.It does get decent mileage(bout 14-15 out on the road) with the mesh Tommy Lift gate and the cattle racks.Honestly,if you let the gate down on the chains(not up)its like night and day on power.I never was happy with the way the gears are spaced in that NV either.The 2-3 spread is annoying at best.I thought if I found a 92-93 cluster and harness and pull the electronic pump off I could stick that 6.5 in.The last one I got has really bad rust on the motor and pulleys ect and didnt want to use it.This one didnt sit as long.Im not starting it until I change the oil and fuel filter.We towed her home today.I cant EVER get a GM8,always 3-5s.

Hate to bring up an old topic, but a 95 454 is still a throttle body injected 220hp slug. I had an 89 and a 94, only difference was the 94 had an aluminum intake and another gear.... 1996 got the Vortec 454 which brought the specs up to 290hp/410tq.. It will absolutely run circles around a 6.5 and get similar fuel mileage..

One of the guys I work with has a 2003 Avalanche with the 5.3 gasser (295hp/330tq) and it totally outpulls my 6.5 up the same mountain with my car trailer and Camaro on it.. I max out at around 40mph with the 6.5 while the avalanche will do 65 with the cruise control set.. The avalanche gets better mileage than my blazer empty AND towing..

[Buddy]

I think you need to upgrade your truck man :) We all know it sucks stock, what do you have on it? Could you fill out your signature?

[tdijetta99]

ok.. signature updated.. It doesn't run bad.. it's just never going to outpull a vortec big block.. ain't gonna happen..

[Buddy]

Get yourself a performance chip from any vendor and some high output injectors, cone filter air intake, a cooling upgrade (130gph water pump and Dmax fan/clutch) and you'd be amazed. You also only have the 1500 version, like me, and Vortec Big Block come in the 1/2 tons?

With the L56 "S" engine you are severely underpowered on purpose. The ECM has lower max fuel rate and the programming to support lower fuel rate. Besides EGR (which we both have deleted) the pre-cups are smaller on the L56 than the L65 "F" engine providing a little less power. On the EGR delete did you gut the inside of the intake? OUr 94 intake is pretty bad for power, that rectangle crap pulling in from the fender. Youd be amazed by the new turbo whine you get with an SSDS or similar intake. The later models intakes were actually OK, but our stock intake was not that great.

Besides the power, you dont have a model built for hauling big loads, although I think it can just fine. My 1500 was upgraded to the HD trailering package by its first owner and was used to pull horse trailer on a regular basis.

With the PMD issue resolved and IP's built better now than years ago and we know how to keep the IPs alive, these trucks can be reliable and powerful. There is a non wastegated turbo being sold that fits on the 6.5 that provides better MPG with a little better high end RPM power because of the reduced backpressure. Although my turbo is still original and still going strong.

[tdijetta99]

The 454 from 96 and newer only was available in the 2500HD and 3500, no big block for the 1500's..

Either way the HP output for the 6.5's was similar from the 1500-3500 series.. The gearing/brakes/suspension were different, but the 5-10hp difference was insignificant.. the S engine was rated 190hp/380tq.. F i believe was 180/360 but had a flatter torque curve so they actually pulled a little better...

ALL the 6.5's were severely underpowered from the factory... none produced more than 200hp stock except for the marine applications..

I have a 9.5" rear from a 2500LD (same 3.73's) to put in mine as soon as this crappy 1/2 ton rear lets go... the 8.5 should have never been paired with a diesel in a truck.. I built an 8.5 for my camaro and it holds up fine, but stock it lasted one launch with the slicks before grenading haha..

So far I haven't had any cooling issues, It'll stay under 200 puling the car trailer even in the summer with the A/C on.. Im thinking about the cooling system upgrade anyway because I do plan on getting a chip and marine injectors.. I'll probably just pick up a set of nozzles and swap them myself.. $100 is a lot cheaper than $450, and I have a pop tester...

I took the upper intake piece off and hogged it out, I couldn't believe how small the air passage was.. I'll look around for a non-egr intake to replace it with..

[Buddy]

The F engines had up to like 440ftlbs torque stock and 195hp, and the S engines were less torque, 360 and 180 like you said. So it is a bit different.

You would be really surprised how well your truck could run, as I agree they are dogs when stock. Mine at least had a hypertech chip and a 3.5" Banks exhaust on it when I got it. I'm going to upgrade the exhaust soon though, and output it in front of the rear wheel, not so bad with the long box.

[tdijetta99]

which applications were over 400ft/lbs? I was looking around online for some specs but couldn't find anything other than what I posted.. There's reference on wikipedia to a 215hp, 440tq 6.5 but no application or RPO code.. I see a bunch of other RPO codes for the 6.5.. L49(non turbo 155hp), L56(180hp), L57(non turbo 160hp), L65(195hp), LQM (175hp), and LQN(190hp).

I guess I'm happy with how it runs, but I'm not impressed with it's pulling power the way it is now.. I'm hoping some marine nozzles and a chip will make it tow a little nicer..

Believe it or not, my TDI will pull a car on a dolly up the mountain better than the Blazer.. The blazer handles the weight better and stops better, but the Jetta will outpull it in a straight line with the camaro in tow.. kinda patheitc really.. I used to use the TDI to pull the camaro to the track before I got the truck...

[Buddy]

Power to weight ratio, your Jetta probably weighs like almost 2 tons less at the same horsepower, and up there in torque.

And the Jetta probably cost you more than your truck :) but if you put like $1500 to $2000 of parts into the 6.5 it will impress, and still less than $10k reliable.

The regular stock F L65 engine in 2500s and 3500 pickups was 430 or 440 ftlbs.

[tdijetta99]

Jetta weighs in at 3050lbs, the blazer was 5170 last time I was on a scale, but I had a bunch of crap in the truck so I think it's a little under 5k.. I paid about the same for both vehicles.. The Jetta definitely wins in the power to weight thing, the 180/300 was at the front wheels..

You have any resources for that L65 spec? Only L65's I can find are 195/380 in any application, even the P chassis motorhomes..

[Buddy]

Your Blazer is only 5000 lbs. Thats insanely light for this engine to lug around. You must have had that Blazer a long time to have paid about the same.

This site sponsor has a graph of stock power at the bottom of the stores FAQ page, and when I googled got this
http://www.media.gm.com/division/chevrolet/products/archive_prod_info/98chevy/ck/engine.htm#l65die

[tdijetta99]

I kinda paid too much for the blazer and got a good deal on the Jetta.. ended up paying 8k for each.. wait I think I paid more for the blazer.. kinda shady used car dealer on Ebay.. either way i was looking for a 94 diesel blazer in good shape for a looong time.. the blazer I got almost 2 years ago, had 130k on it and it was spotless inside and out, looked like it had 20k on it.. no plow, no extra wiring, nothing that GM didn't put there..

The TDI I got in 05 right before the fuel prices jumped..

[bigde53]

One of the guys I work with has a 2003 Avalanche with the 5.3 gasser (295hp/330tq) and it totally outpulls my 6.5 up the same mountain with my car trailer and Camaro on it.. I max out at around 40mph with the 6.5 while the avalanche will do 65 with the cruise control set.
NO WAY!! I had a 99 1/2 ton with the 5.3 and it was a total pig no comparision to the truck I have now. That POS couldn't hold OD towing 2k on flat ground. I say you need to upgrade what you have. My truck runs great and it weighs in about 7k empty so I would think a light blazer would be like a sports car sort of.

[deerefanatic]

Of course you couldn't hold overdrive pulling uphill with the 5.3. Neither can a 454, even though it has 100 MORE horsepower than a 6.5 and the same torque as an F vin 6.5 (more than an S vin 6.5) It's simple and expected: Gas burners have a much higher torque band than diesels, especially turbo diesels. A gas burner needs to turn hi revs to make horsepower..... That's why good-pulling gas burners will have slow gears in the back (4.10's for instance) while a diesel can live, and sometimes even prefers faster gears like 3.42 and 3.73's.... In fact, with my 6.5, I've found that it's best to NOT let it drop out of overdrive because it noticeably looses power over 2800 rpms compared to when it's lugging along at 1800-2000 rpm......

The only way to say that x gas burner can't haul as much uphill as y diesel is to drive them both in their UNIQUE power band with the same load.. And when keeping that in mind, you'll find the 6.5 is rarely the winner.

What you guys forget is until the Duramax, GM marketed the 454 for POWER. the 6.5 was for COST EFFECTIVENESS as you got the same horsepower as a 350, the torque of a 454, and the fuel efficiency of a big V6 or small V8..... On fuel that at that time was much cheaper than Gasoline... Diesel was not GM's power motor until the Duramax....

[2000RIG]

what kind of torque can you get out of a 6.5td with all the bells and whistles, if stock is 430ftlbs what would with air ,exhaust,marine injectors and 80hp reflash?

[Buddy]

Ian Carver in Maxxtorque Fall08 issue got 590 ftlbs @ 2300rpm with 303 horsepower @ 3400rpm, but he was using propane fumigation and water meth injection and nitrous. So you can probably get 530ish ftlbs without the extra injections. If you live in moderate to hot climate areas water injection is a great idea, much better than an intercooler. otherwise there is also an alternative turbo, non-GM, that has been developed to work on the 6.5TD that is non wastegated and more efficient and lowers IATs a lot too, because of the reduced backpressure needed to turn the turbo.

[deerefanatic]

590 lb-ft..... Ahhh..... Just creeping into cummins territory. :D I couldn't resist!! :D

[tdijetta99]

NO WAY!! I had a 99 1/2 ton with the 5.3 and it was a total pig no comparision to the truck I have now. That POS couldn't hold OD towing 2k on flat ground. I say you need to upgrade what you have. My truck runs great and it weighs in about 7k empty so I would think a light blazer would be like a sports car sort of.

well something was wrong with your 5.3... push the skinny pedal all the way down and they wake up and shine at high rpm's.. That avalanche would pull 1st gear to 45mph, second to a little over 70.. The 5.3 is an awesome engine if you're not afraid to rev it up.. the 6.0 in the 2500's is a nice one too..

My blazer runs fine, but it's as slow as you would expect 190hp in a 5000lb truck to be.. It seems to make the best power around 2500-3000rpm though.. falls on its face at 3300..

[my95diesel]

My diesel outpulls my tbi 454 and tbi 350. Faster than the 350 and better fuel economey than both. Only complaint is this blown head gasket. As far as starting, I live in Michigan and havent had a problem yet and only plug it in when its 15degrees or lower. She still fired right up with blow head gasket it neagtive weather with with chill when plugged in! I love my diesel

[grancito]

I see posts of how much more HP the 454 puts out than a 6.5. A friend has one the same year as mine and it is around 200 HP and less torque, must give it a run against mine.

[tdijetta99]

yeah the 454's were pigs till 96 when they got the Vortec MPI.. the TBI's were rated only 220hp, the carbureted ones were even worse..

Should be a good race haha

[Buddy]

My truck is very quick and it weighs like 6800lbs, so your blazer should be speedy. Just need to get rid of that crappy E-PROM program.

tdijetta99 Do you know your IP model type, its on the side facing the intake, so need inspection mirror if you dont know. And the code on your E-PROM inside the ECM? Its fairly easy to check. I might be able to send you another chip to try out, a stock L65 one, which would wake an L56 up. I also noticed turbo spool faster and louder whine with the SSDS intake.

[tdijetta99]

I'll get in there and look tomorrow, I thought I worte it down when I had the intake off but I gues I didn't.. I had to pull it off when I relocated the PMD because the harness was routed wrong for some reason and it wouldn't reach..

I definitely want to wake it up some.. it has no excuse to be out-towed by a diesel Jetta, hahaha
Some days it runs MUCH stronger than others.. I need to get some gauges on there and see what it's doing..

[Stumped]

My 3500 HD(94-5,I forget) is a slug at best.That 454 doesnt make any power at any RPM.And the gear spread on that nv4500 leaves a lot to be desired.I need a 93 diesel dash cluster so I can drop a 6.2 turbo in there

[Buddy]

I definitely want to wake it up some.. it has no excuse to be out-towed by a diesel Jetta, hahaha
Some days it runs MUCH stronger than others.. I need to get some gauges on there and see what it's doing..

So do you have the PMD on the intake, from SSDS, and how long has it been there? (about a year ago they switched to the higher temp rated D-tech type) And youre supposed to tighten the bolts every 3k or so, according to SSDS. And if you took off the IP, did you set the TDCO and IP timing correctly? A PMD and timing could be why its such a dog.

[bigde53]

well something was wrong with your 5.3... push the skinny pedal all the way down and they wake up and shine at high rpm's..
Thats the problem I did and it screamed all the time I used to get 9-10 mpg towing a 2k boat now I can tow 7-8k and get 15mpg and not have to scream the motor. My diesel outpulls my tbi 454 and tbi 350. Faster than the 350 and better fuel economey than both.
My buddy had a 97 3/4ton 6.5 and wanted a 1ton he bought into the 454 hype and got a 99 454 1ton and hated it he got a dmax in 01 and likes it but he has driven mine since Ive worked on it and says it pulls just as good. Needless to say he wishes he still had his 6.5 with alot more doe in his pocket!

[trukdoc]

...you lookin for a tach dash or regular dash got a spare out of the beast...93...

[UGLYTRUK]

I have a few 6.5's, and my current one on the road is a '95 4x4 Suburban I just drove back from Phoenix, and rust proofed, and even tho it has 240k, it runs great.

My air pump is now making a bit of noise, and I bought a new A/C Delco one, but I've been advised to just trash the old one, and buy or build a spring kit.

I've also recently lost boost, and pulling the air cleaner elbow shows the turbo spooling up, but my boost guage just sits on zero, and I've much less power going uphill, like my DD 84 6.2 Sub.

My fuel mileage is also 11, and I've been told maybe my injectors are weak, yet it only smoke for a few seconds cold, even tho it's been below freezing!

It was 16 when I drove it to California from Phoenix, and 11 when I loaded a Corvair pickup on a trailer and drove back east. Now it's 11 driving moderately! No jackrabbit starts or above 65mph.

So.... Should I install marine injectors, or just keep it stock? What about the supposedly crappy air box? And recently my throttle has been acting up. I got a used one from a '97, but the wire colors are different. I just turn off the engine, and it comes back to life

[Racer5551]

I have a few 6.5's, and my current one on the road is a '95 4x4 Suburban I just drove back from Phoenix, and rust proofed, and even tho it has 240k, it runs great.

My air pump is now making a bit of noise, and I bought a new A/C Delco one, but I've been advised to just trash the old one, and buy or build a spring kit.

I've also recently lost boost, and pulling the air cleaner elbow shows the turbo spooling up, but my boost guage just sits on zero, and I've much less power going uphill, like my DD 84 6.2 Sub.

My fuel mileage is also 11, and I've been told maybe my injectors are weak, yet it only smoke for a few seconds cold, even tho it's been below freezing!

It was 16 when I drove it to California from Phoenix, and 11 when I loaded a Corvair pickup on a trailer and drove back east. Now it's 11 driving moderately! No jackrabbit starts or above 65mph.

So.... Should I install marine injectors, or just keep it stock? What about the supposedly crappy air box? And recently my throttle has been acting up. I got a used one from a '97, but the wire colors are different. I just turn off the engine, and it comes back to life

Fix the vacuum problem you have and you will likely get your performance back.
Without proper boost you are overfueling the engine and its only defense from meltdown is to defuel.

If it has never had the injectors serviced it is due,although the marine injectors are touted as +40 hp,there is no way they can deliver that.
The IP is the bottleneck when it comes to fuel delivery with these engines so stock injectors are all you will ever need and probably better performing.

[UGLYTRUK]

I had an intercooler pipe come disconnected, (did I mention there's an aftermarker IC?), anyhow, I was driving 10 across the top of Texas, and all of a sudden I notice HUGE amounts of black smoke, and 1200 EGT. I slowed down, and wondered what was wrong. I eventually found the clamp loose, reconnected it, and everything returned to normal.

In this case, the EGT never goes above 800, even on the way to our farm up a good hill, and zero smoke, but power's down. I believe the wastegate is functioning, and closing fully. I tinkered with the actuator and rod, and the turbo is spinning, but???

I really don't need extra power, I'm an OG. Just maybe a big exhaust, like on my other 94 (dead) Suburban, and a nice less restrictive air box and the spring kit.

If injectors are weak, how does one test them? Would the engine smoke? The only issue I noticed is kinda reluctant starting when warm. It starts great cold, even 10f! Warm it spins for a few seconds, more than any of my other 6.2's or 6.5's

[deerefanatic]

I'm going to throw into this thread that since I last posted here, I picked up a 95 Dodge Cummins.. it now has twin turbos, big injectors and a fully built up billet transmission.. Putting down well over 500hp/1100 lb-ft of torque to the ground.

All you guys that say the 6.5 has plenty of power for towing and pulls just as well blah blah blah are just fooling yourselves.. :D I can tow 20k and walk away from your 6.5 empty. :D

BUT, i do still own my half-ton 6.5... It's unique and makes a great little grocery getter.

[Buddy]

I'm going to throw into this thread that since I last posted here, I picked up a 95 Dodge Cummins.. it now has twin turbos, big injectors and a fully built up billet transmission.. Putting down well over 500hp/1100 lb-ft of torque to the ground.

All you guys that say the 6.5 has plenty of power for towing and pulls just as well blah blah blah are just fooling yourselves.. :D I can tow 20k and walk away from your 6.5 empty. :D

BUT, i do still own my half-ton 6.5... It's unique and makes a great little grocery getter.

Wow, nice comparison, NOT!! Just because you couldnt set it up as well doesnt mean its not possible. You had to modify that Cummins to get there. Its not as conventional upgrade on the 6.5 but that doesnt mean its that difficult.

I modify my own PCM programs, and can tell you the retailers never tapped the potential of the DS4, on fuel delivery potential. That and the people that try to tell you the GM8 is the best for the 6.5 is ridiculous, an HX35 off the cummins is too small for the 6.5 to get the right pulling power, yet the GM8 is smaller, and more displacement than the Cummins. GM set it up as a grocery getter, that was unfortunate.