Your Opinion on the 6.5L/6.5L Motor

[6.5SmokeStack]

I have been reading around on this website and I was just curious what is your view on this motor? Do you think it was a decent design? Deffinatly has more potential? I just wanna see how you guys would rate the motor, compare it to a different motor. Because the really annoying 7.3 Ford guys are a pain in the butt, so i gotta give them something to run from! Thanks

-Nick

[Shlep]

Being a Ford Tech, let me tell you from experience that the 7.3 is a good work horse as long as you can afford the huge repair costs when she breaks, and the tend to break fairly often from what I've seen. On the other hand my 6.5 has been a die hard workhorse for the 200,000 I've put on her since Sept 03, most have been pretty easy miles but in the last few months I've hauled more then my fair share of weight, including my 78 F250 4X4 on 40" Swampers, on a 26' trailer loaded with everything including the kitchen sink, she toped the scales in Michigan at a hair over 11,000lbs. :D

As far as performance you're somewhat limited but then again the 6.5 was never intended on being a race engine, more for working and getting about the best mpg you could. The biggest downfall is the lack of breathing, both in and out but Walt has taken care of that :D

Anyone else?

[6.5SmokeStack]

Well good thing your a ford tech, I like your in put, and walt has deffinatly done an awsome job with making SSDiesel Supply for everyone with 6.5 and 6.2. I would rather it be a work horse than race, less likely for me to get a ticket when im done with the upgrades haha, lets hear everyones input :)

[Sundance]

I've had Three 6.5 TD's and they all performed well. The
only issue was the other stuff like speed sensors, 4x4
actuators, ignition switch, etc.

That said........ I do like the new Ford's look and would
love to hear more about it. I also covet a DuraMax and
Allison more than any Ford at this point. Too spendy for
even a used one as of yet. But someday.

[6point5]

One other factor, the tranny seems to be an on going pain with the Ford product, no matter if the engine is good or not. A lot of powerstrokers I know have tranny problems under 50K miles, more do than don't.

[Shlep]

Yeah that torqueshift was a real nightmare when it first arrived but they seem to have the bugs out of it now thankfully

[sixnickel]

Both the Cummins 5.9 and the Ford (International T444E) Power Joke are great engines BUT they were both designed as medium duty truck engines then they stuffed them into light duty trucks. They both are about 300 to 400 lbs heavier than the 6.2/6.5. I have had little to no experience with the Cummins we just got our first one at work about 5 months ago all I have done to it is PMS. It runs great, pulls good, and is quite. All I have heard is the transmission is the weak link in it. Great engine to bad it has a Dodge wrapped around it!! Now the Power Joke/T444E I have 4 of them at work 1 F250 and 3 IH 4700s All they do, is want to work. But when they do need work $$$$ I have replaced a lot of throttle sensors (APP) cam shaft position sensors and injectors (about $400 each) they are expensive the do a PMS on, they take a lot of oil and filters are not cheap. But they do deliver a lot of lumber. The 6.2/6.5 is the under dog of the bunch but if you set it up correctly it can run and run hard with the with the big boys. But you got to remember it was designed as a light truck engine. And the best part is it has a nice handling, nice riding GM Pedigree truck wrapped around it!!! Don't forget the Dodge and Ford are MUTTS

[surreysinner]

I like my 6.5 , but only for reliability. Power wise its a dog. I got 3" exaust no cat, downpiped,boost control(runnin 12psi) and to me its still a slug and doesnt impress me towing.

Its paid for though so i will do the chip, injectors and cooling mods and see how it is then.

[RckyMtNDeZL]

Power wise its fine, what in the hell do I need 400hp for? Can anyone actually use this? Fuel economy is great, reliability is far superior to any diesel out there. I know MANY FORD owners who spend a grand every 3 months in repairs. I tow,it gets hot on occasion but a new exhaust should fix that on uphill hauls. I have always believed chevy makes the best diesels, its still true. If you think otherwise...why are you posting here? Go somewhere else with that BS! My 6.5 has been good to me, power isnt everything, but you know what they say about those power hungry dudes in huge trucks.... always lacking something.LOL

[6.5Jonny]

Having spent twelve years working in an engine rebuilding shop, my opinion of the 6.5 GM diesel is not a good one. I see more problems and failures in 6.5 diesels than all other light truck diesel engines combined. Poor design and poor quality parts do not make for an overly reliable engine. Sure, you might get 200 or 300K miles out of the engine but the real difference between the 6.5 and its competition is that when you try to rebuild the 6.5 there is usually very little left that can be rebuilt.

The crankshaft in these things is a nodular cast iron piece of junk that has no business being in a diesel engine to begin with. They are quite fragile and are prone to breaking when used for anything other than light duty work. The crankshaft grinder in our shop hates 6.5 cranks. If they show the slightest sing of a heat related failure and are a bit bent as a result he won't even try to grind them. Seven or eight times out of ten the crank will break when he tries to straighten it.

Easily 90% of the blocks develop cracks through the main bearing cap bolt holes or number 7 and 8 cylinders. I have seen the main webs on these blocks crack so bad that the a big chunk of the block actually breaks loose. GM drilled the main saddles on the block to fit piston cooling jets in '96 and further weakened an already weak block. It's quite common to see a crack develop through the squirter hole and travel up into a cylinder on its way to becoming a mysterious internal coolant leak. It is also fairly common to find cracks around the cylinder head bolt holes. Those can travel across the deck and down into a cylinder on occasion. Scuffed pistons are big problems as well, usually in cylinders 7 and 8.

90+% of the heads are junk as well. Cracks galore, pounded seats, loose precups, etc. Usable cores are scarce and not worth the effort to try and bring back to spec. I put new castings on every one I build.

Head gasket failures are very common and many times replacing the gasket is a band-aid solution because of the wear from the previous gasket on the deck of the block affects the clamp load on the new gasket. GM's oil cooler line setup is a joke too. Leaks and broken lines there have killed many an engine. The injection pump and the electronics therein are another whole world of problems...

The 5.9 Cummins and the 7.3 powerstroke are far better designed engines from mechanical standpoint, and it's rare to any of the catastrophic failures that are so common in the 6.5(but I have seen them break).

With the Dodge you get a great engine but a weak diff and and even weaker tranny wrapped up in a truck that might as well have been put together with chewing gum and band-aids.

The 7.3 ford is a little better but the injection system is a nightmare and hugely expensive to fix when it starts acting up. The E4OD auto transmission is a weak point as well. The newer 6.0 diesels are worse than the old 7.3 for fuel system problems...

So after saying all of that, you're probably wondering why I own a 6.5 powered truck. It's simple. The truck is good even if the engine and fuel system aren't that great. I have a ton of spare parts for it (engine, two IP's, a handful of PMD's, etc) and I'm a mechanic with a fair bit of experience in fixing GM trucks. Besides, I'm too poor to buy a duramax. :)

[harold]

I really enjoy the different opinions written on this message board. I have a 6.5 in a 96 burbo. I do have a few questions about it after reading all your input.

With the addition of walt's water pump and 4" exhaust kit, wouldn't that solve the head cracking problem and keeping your motor cool?

And flushing your fuel system every couple to three weeks and keeping a good fuel filter should keep your injection pump and injectors running smooth?

I also change my oil every 3000 or sooner. I hope this will help me get at least 300,000 or more miles out of it. I really like how my truck tows my jeep and gets me around. It has left me stranded a couple of times, but they all do that if you drive them don't they?

Thanks again for all your input on my questions that I have posted. It has really helped me with my truck.

[drfinn2k2]

I have a 98 6.5 with 290K on a 3500 with a regular truck bed on it. I only tow a fairly light tool trailer so power is not a problem. It will fly. Gets great fuel milage and runs clean. I've only had it a couple of weeks. When it ran right, I was very pleased. AND THEN........when something went wrong, (Injector pump) bring out the wallet. I went to 3 different diesel shops today and when I mentioned 6.5 Turbo, mechanics would run and hide and want no part of it. Most of the guys I talked to said they were pile of @#!&. and refered me to the Cheverolet dealer. $$$$$$$$$$$$$$$$$$$$ Ouch!

Made me kinda wish I still had my old truck along with the stack of cash I had to boot to get it. BUT, MAN SHE SURE IS A PRETTY TRUCK!

[Alvy1976]

Now that's what I like to see. Johnny is honest about his bad experiences with the 6.5 but still drives one, nice job indeed. I've had my fair share of probs with my 94 6.5 dually but like Johnny here, I love to hate it. Sure, everybody would love to spend 50 grand on a Duramax truck if they had it, but the fact is that not too many people do. Many people, like us, have a ton of miles on their truck, are constantly working on it and spend money on it, but love it because they OWN it. I don't have a giant truck payment and I've accepted the fact that because of that, I will be spending some dough on fixin mine which doesn't bother me. I just spent 2,500 bucks on a rugged transmission with a Trans-go reprogramming kit because I lost reverse, O/D, etc. not to mention brake lines, infamous lift pumps, wastegate solenoid, headliner, tires, etc. etc. I've got 140k on mine and am refusing to get rid of it until 140k more. I don't care if I have to buy every piece to fix it, I will. I got so scri-zood on a Toyletta Tacoma lease (which was my fault) that I bought my GMC for 1,200 bucks and basically have been redoing it ever since. My lease is up in October after 4 years and I'll never do it again. I'm a mechanic by trade so I can get through pretty much anything that it throws at me of course also by forums like this and the diesel place. Good luck to all and long live the 6.2ers and 6.5ers. Alvy

[jamiewright123@hotmail.co]

I am sorry to say I am not as enthusiastic as the rest of the people on this board. I got into these things in a 1986 suburban a while back. Great truck! Still running today. Next one was a 1989 6.2 4X4. Ran good till about 150k. Cracked block. Put in a 1992 6.2 take-out engine from Avant salvage down in Georgia. Ran good for about 50k. Lost the heads. Rebuilt it. Reman heads. Honed, rings, rods, mains, everything. Lost another block. Bought a 1993 6.5 turbo 4 door 4X4. Less than 100k, drove it about 2 months before the heads cracked. Replaced them. Ran great. Drove for 2 days before noticing coolant back in oil. Went home and pulled serpentine belt and thermostat. Let it run for a bit and sure enough, bubbles. Cracked block. I have now put together a 6.2 military shortblock with the 6.5 reman heads and turbo setup and have yet to put it in. Hope I can get more than 50k out of it, cause I have made more payments on this junker sitting in my shop than I have driving it. Anybody want to buy one? Body is perfect! Any input to help me get a few miles out of it would be greatly appreciated!

[1999GMC]

GM cars and trucks have always treated me well. I have a buddy from High School who has always been a GM owner as well. I had a 1985 Suburban and he had 1989. I bought a toyhauler and my Suburban didn't pull it very well. So I sold my Suburban and bought a 1999 GMC crew cab. My buddy works for GMC. He told me I don't want a 6.5L. They are gutless. The ones he works on though are all contractor trucks. So when he bought a toyhauler he decided to buy a powerstroke. A 1996. He has had more problems with that truck than you can imagine. We finally got all the bugs worked out and the truck is running good. No check engine lights anymore. We go camping and he isn't pulling hills any faster than me. So where is all this powerstroke power. Before when the check engine light was coming on he would have to pull over and shut the truck off because it would barely keep 35 mph floored. I don't regret not buying a powerstroke once. So far my 6.5L has been sweet.