Towing power

[tompdw]

I have a stock 1998 K3500 dually with 4:10 gears. My owner's manuel says I could only pull 10,000lbs with my gooseneck/ fifth wheel hitch. This seems awfully low considering some 1/2 ton gas burners can do this. Does this seem right or is it that much of a dog with the pulling?

[Sundance]

You can do better with mods........Exhaust, cooling, intake,
computer reflashed, etc.

[Husker 6.5]

I have a stock 1998 K3500 dually with 4:10 gears. My owner's manuel says I could only pull 10,000lbs with my gooseneck/ fifth wheel hitch. This seems awfully low considering some 1/2 ton gas burners can do this. Does this seem right or is it that much of a dog with the pulling?

The problem is not with the engine, it is with the total rated capacity of the chassis. Properly modded, these engines can handle 30,000 lbs gross. Remember, these are light-duty trucks. Vented rotors/titanium pads, rear disc conversion, spring/wheel/tire upgrades will increase the total capacity.

Husker 6.5

[tompdw]

Husker, Thank you. This is the stuffI need to know. My girlfriend is looking on getting a gooseneck horse trailer and total weight is usually around 12,000 to 15,000. I really don't want to touch my engine because it runs great down the line but I am worried about the weight. Eventually I will get a better flowing exhaust and intake but not much else. What does my chassis need?

[Husker 6.5]

Husker, Thank you. This is the stuffI need to know. My girlfriend is looking on getting a gooseneck horse trailer and total weight is usually around 12,000 to 15,000. I really don't want to touch my engine because it runs great down the line but I am worried about the weight. Eventually I will get a better flowing exhaust and intake but not much else. What does my chassis need?

Follow me on this and trust me if you want trouble-free towing.

First, get yourself a triple gauge set to save your motor and tranny.

Second, add a minimum 30,000 lb GVW external tranny cooler and an extra cap. tranny pan. Think seriously about adding a multi-clutch torque converter, and rebuilding your tranny with heavy-duty parts/ high friction clutches if over 200k on tranny.

Third, brakes. Go to drilled rotors on front with high friction pads (titanium or ceramic) at a minimum. Consider aftermarket multi-piston calipers also. If you want to go total, get rear discs off a P-30 step-van chassis.

Fourth, rear suspension. Overload leaves or air bags for carrying the extra load. Speaking of load, load range E tires all around.

Fifth, SERIOUSLY consider upgrading your motor, the increased power will actually make it easier on your drivetrain overall. Exhaust first, intake, #9 resistor, marine injectors, ECM.

Make sure all systems are functioning normally; steering, A/C, vacuum, etc.

Hope this helps.

Husker 6.5

[tompdw]

I have about 88,000 on the engine. When my brakes and ball joints went bad I replaced them with heavy duty brake pads and rotors. I have hd shocks as well. My tranny had new solonoids and speed sensor installed. The truck came with the huge standard radiator, oil cooler and tranny cooler. I have new tires E rated already on all 6 wheels. I was thinking about helper or additional leaf springs on the rear. I don't know much about what to get for hi performance stuff for a diesel but I know it needs to breath first. When my pipes go bad I was thinking about getting a 4 in diameter and a better air box. What are the #9 resister, and marine injectors, ecm? How bad will kill m fuel milage? I am about 14-15 mpg

[Sundance]

If you see my 95' info below (not flatbed) the mods I've
done get me 18 mpg with 4.10 gears. I've hit 20 mpg
once when empty.

[Bluevee33]

With my 95 I got 21 to 22 towing a 2 horse bumper pull trailer over a 4700 ft pass! I had a helper spring on the rear! Once towed a 13000lb trailer down I5 on the flat straight section here in Oregon.. Got 13mpg there!!

Open that exhaust and put the ss diesel intake on it!! That alone is amazing for towing!! KEEP YOUR TRANNY COOL!!!

Another thing!! Check your wastegate solenoid!! Mine went bad while on a 700 mile trip and killed my mileage!! Spent an extra 100 bucks on fuel because a $40 part when bad!!

[tompdw]

How would I know if my water pump is the high outbut or the regular duty one?

[Husker 6.5]

How would I know if my water pump is the high outbut or the regular duty one?

Your 98 has the 130 gpm on it from the factory, it's part of the cooling upgrade the factory did in late 96 - dual t-stat and 130 pump.

Check the front of your vehicle carefully, the two coolers you see there in front of the radiator are for the engine oil and the power steering pump! Unless a previous owner added an external tranny cooler, those are the only external coolers (don't confuse the A/C with a cooler). GM used an internal tank exchanger for the tranny, so if you have three coolers, check the size of the aftermarket cooler and compare it to mfr's sizes to get an idea of the rating. If only two coolers, add a minimum 30,000 lb GVW cooler. Keep the tranny's heat out of the radiator, and the cooling system's heat out of the tranny. Every 20*F drop in tranny temp doubles its life.

You didn't mention gauges, if you don't have them, get them if you are towing! EGT and tranny temp at a minimum. High EGT will kill an engine/turbo quicker than anything else. Same goes for tranny temps.

You're already towing? Don't wait for an excuse, scrap the POS factory exhaust system and install a 3" into 4" system. The factory "3 inch" turbo downpipe has a "bend" (crush) in it a couple of feet from the turbo to clear the frame. This "bend" gives the pipe a 3/4" by 3" internal cross-section, chokes the hell out of the engine's ability to breathe, and drives EGTs up!

The #9 resistor recalibrates the fuel delivery for about 6% more fuel, marine injectors give better atomization of the fuel and can handle more fuel - give you about 40 more HP. The new ECM reprogrammed controls fuel delivery parameters and boost, and with either a 40 or 80 HP tune. Combine everything together, and you will see an easy 100 HP, 200 lb/ft increase. All things being equal, you will actually see an increase in your fuel milage due to the engine operating more efficiently, just keep your foot out of it from playing with all those ponies and spinning your duals!

You don't give the mileage on your chassis/tranny. New solenoids and a speed sensor are fine as repairs, but high milage clutches and steels in your transmission, or the stock converter, won't hold up to serious towing with or without the engine power mods, transmission cooler or not.

Use the search function on the taskbar at the top of the page to find plenty of threads on these topics, and peruse Walt's FAQ section. Most, if not all, of your questions will be answered.

Hope this helps.

Husker 6.5

[hauling8]

If you really want a good suspension get the road master suspension and put that with your springs. believe me its a lot better then adding springs or air bags. i pull very heavy loads all day long. i love it, you cant go wrong with it.

[Shlep]

Hey Husker, thanks for all the info. My 99 used to pull pretty hard but this year I just got a 30' 5th wheel and when I brought it home it felt as if it was struggling with the weight. I had the mods you suggested in mind already but it's nice to see I'm in the right area instead of wasting time and money :D

[sshewins]

Another thing to put on the 'must do' list (and on the super cheap) is this: pull your radiator out, soak it with some sort of chemical cleaner like scrubbing bubbles or greased lightning or similar (the super cheap part), run it down to car wash, and blast it good (not to worry, the psi generated isn't enough to bend fins) and watch all the BLACK CRUD run down the drain. Your radiator MUST be ABSOLUTELY SUPER CLEAN !!!!! It can't dissipate the heat otherwise.

Now check behind those coolers for additional crud packing (weeds, leaves, grass, occational flying bugs, etc...) and clean as nessesary.

Now would be the optimal time to inspect and replace as needed the hoses and most deffinately the stock clamps. When in doubt, change out T-stats with AC Delco stats ONLY!!! Add fresh coolant/water mix and youll be one cool dude for sure!! Add two bottles of water wetter and I dare you to try to over heat it. My moneys on ain't gonna happen.

By the way, hows the fan clutch?

Before you attempt to make gobs of HP, which as we know, generates gobs of heat, you have to be able to keep the heat in check/controll. Speaking of heat, have you thought about adding an intercooler? If you're half serious about towing, you'll need one. Best part is for around 3 - 400 bucks you can fab one up with parts from _bay. Hope this gives you some things to think about and even consider,

[deerefanatic]

And when you put the coolant back in...... DO NOT USE that $#&%*^! Dexcool!! It's the absoulute WORST stuff on the planet... I used Zerex G05 (Mercedes spec coolant).. It's made of a different kind of glycol (propelyne glycol) that lasts longer and cools better...... And it has an awesome anti-corrosion package..... Best part? It won't turn to mud in your cooling system like Dexcool......

[Stumped]

DEXCOOL IS NO GOOD! I just recieved a notification in the mail that I may have some $$ coming because I had to replace 3 intake manifolds on the last 2 gm products due to Dexcool.It is worded somewhat odd,but basically says the coolant killed those composite intakes.I quit buying late model GMs for daily drivers for this reason.Small block chevy has been around for what...45 yrs...why is the intake manifolds failing??Dexcool met ANSI specs?I couldnt keep last 4 late model GMs on the road.CPI injection on the 98 4wd was a joke,Bonneville ate a manifold and fuel reg before 80,000 miles and the 98 z71 needed two intakes in 4 yrs. BS! I went Euro trash and bought a Volvo C70 high pressure turbo coupe with the 2.3 inline 5cyl. 20 mpg city,27-33 hwy with 13 lbs of boost(after factory off road re-flash of the ecm),intercooled,NO overdrive(slightly underdriven actually) and a blast to drive.After off road re flash,picked up 2 mpg in mileage??Built like a tank,awesome fit and finish.Check them out.Tom Wakinshaw racing built them for Volvo(only the HPT coupes) right beside the Holden GTO bodies.TWR built sev cars for Chrysler,GM and ferd in the late 60's early 70's.

[Stumped]

Uh...those mileage #s...thats only when the boost says "0".It will get down to 2 mpg if you want.

[trukdoc]

...that ton 4by will pull whatever you tie it to...don't tow in o/d and watch water temp. gauge... should already have plenty of spring but they make an air bag helper spring set that's pretty resonable in price and an easy install...walt's open air set up $110.pretty cheeap....all this other hotrod stuff is cool but gm built a stud in the 6.5...I promise anH1 in full battle gear outweighs anything you want to try...and they fly in desert sand...

[JD_countryboy]

Another thing to put on the 'must do' list (and on the super cheap) is this: pull your radiator out, soak it with some sort of chemical cleaner like scrubbing bubbles or greased lightning or similar (the super cheap part), run it down to car wash, and blast it good (not to worry, the psi generated isn't enough to bend fins) and watch all the BLACK CRUD run down the drain. Your radiator MUST be ABSOLUTELY SUPER CLEAN !!!!! It can't dissipate the heat otherwise.

Now check behind those coolers for additional crud packing (weeds, leaves, grass, occational flying bugs, etc...) and clean as nessesary.

Now would be the optimal time to inspect and replace as needed the hoses and most deffinately the stock clamps. When in doubt, change out T-stats with AC Delco stats ONLY!!! Add fresh coolant/water mix and youll be one cool dude for sure!! Add two bottles of water wetter and I dare you to try to over heat it. My moneys on ain't gonna happen.

By the way, hows the fan clutch?

Before you attempt to make gobs of HP, which as we know, generates gobs of heat, you have to be able to keep the heat in check/controll. Speaking of heat, have you thought about adding an intercooler? If you're half serious about towing, you'll need one. Best part is for around 3 - 400 bucks you can fab one up with parts from _bay. Hope this gives you some things to think about and even consider,

I'll find out shortly. I know rads get dirty, but HOLY CRAP. Pulled mine today as im installing the cooling upgrade. Its easyier that way. 3 cans of engine degreaser and a garden hose, has the water flowin through it better, but a long way from done. Pressure washer will be tomarrow. I can't believe my truck never overheated just crusin. No wonder it was heatin up sittin still. And fan clutch, i know was junk, but heck the fluid came out the front of it, covered the spring and aint no way it coulda worked properly. Amazing what you can find when you tear into it deeper.

[Shlep]

Well, the new injectors were installed last week, cooling system flushed, inside and out..... rad was pretty clean all in all, added water wetter as someone suggested and she runs nice and cool now but still no power to pull the 5th wheel. Turbo is making a constant 10-11 PSI of boost, but I can feel the lack of power even when running empty. Any ideas fella's I'm running out of ideas and patience with my old girl. Sad part is last fall she pulled my 78F250 on a trailer with a combined weight of 10,000lbs with no problem at all but this year she's a hurtin unit :confused:

[grancito]

Check the lift pump pressure, and flow of fuel. Also if there is an SES code it could be defueling. Also exhaust could be restricted.

[Shlep]

Lift pump was just replaced and fuel flow is very good, also thinking of an exhaust issue so I'll be ordering my 4" system this week and trying that, Thanks for the help Grancito

[Bluevee33]

I felt the same way with my truck!!! No power after it hit 100k.. I added the marine injectors expecting big things and didn't feel a thing.. I was getting ready to trade the truck in for a duramax and decided to throw a little more cash into the truck!! I added Walt's intake!! WOW!! You can hear the turbo, feel the turbo!! Then Lost it all again!! I could hear the turbo but it felt like i didn't have the power!! Didn't flash any SES codes but I swapped the wastegate solenoid and all the power came back!! Then added the 4" exhaust and put on a new PMD with a cooler and WOW!! Again!! All kinds of towing power!! I towed our horse trailer (3 horse, with 3 horses) up our hill.. 1200 feet up in 2 miles, at 45 instead of 25 with black smoke.. Smoke was gone power was there and It was fun to drive empty!! Any corner.. just floor it to go sideways!!!

[JD_countryboy]

Are you sure your fuel flow is good now? OPS will work one time, next time dead. Starve the ip of fuel and you got a dog for a truck. How about fuel filter? coulda got a bad tank of fuel. Could be your exhaust. Could cut out the cat and put a straight pipe in it for the time being to see if it helped. Just a couple ideas.

[Shlep]

Well the lift pump produces 5lbs constant pressure under load ( new 2 weeks ago) filters are changed every 2nd oil change, jsut ran 2 tanks of fuel through it over the last 3 days on a road trip, just hung the 4" system on her today, marine injectors last week and I still have a lack of power compared to what I had, going to get a proper boost gauge this weekend and see if it's a lack of boost pressure even though I hear the turbo spool up as soon as I touch the throttle now...... all this to tow a lousy 7700lb 5th wheel :mad: