Learn me Duramaxes...

May be in the market for a Duramax 2500. Want a quad cab, 4 wheel drive, short bed.

A quick craigslist search yields quite a few in the '03-'05 year range with 100k ish miles for +/- $15k.

What should I be looking for and what years are more desirable? What maintenance should I specifically be looking to be done with around that mileage? Which year did Chevy put in the 6 speed Allison tranny?

Truck will be used to haul my race car/trailer, house projects and may be turned into a daily-ish driver.

You want one 04 and a half or newer. (LLY engine code). Before that the injectors require you to pull the covers to access and had some other issues.

My 04.5 has an Allison 5 speed, but GMC had the six in '05 so I'll assume Chevy did too.

I think you want the newest, best cared for truck you can lay hands on from '05 or '06 ideally. Find a southern cream puff then when you get home - put bilsteins on it and let 20lbs out of the rear tires. It rides beautiful for a truck.

My regular maintenance is 10qts of 15-40 every 5k, and a $50 fuel filter every 2nd oil change. Change the trans filter every 25k (easy external), full flush it once at 100k. Diffs and xfer case annually. 2 oz of 2 stroke oil in the fuel every 2nd fill.

At some point your dash will die. There are places to send it for $75 to have it fixed forever.

At some point your ABS wheel sensor will die and it will cost you $175 for a new part because it is rust on the wheel that did it.

At some point a wheel bearing will go bad. It is a $175 part.

At some point the switch on the trans that changes trans gears will go bad. The part costs $100.

At some point every freaking light bulb on the truck will go bad in the same three weeks. Just buy them all when you notice the first one. It will keep you from grinding your teeth to powder every 2nd day.

That is all I got.

You'll hear a lot about bad injectors. That applies to the LB7 (01-04). They are covered by an extended warranty campaign. That warranty was only for 5 years (I think) but they'll all be out of warranty by now, so if you get an LB7 I suggest you find one that has already had them replaced by that campaign. If the seller can't prove it, call a dealer with the VIN and they can verify it.

LLY started in mid 04 and went through 07. LBZ was produced 06-07 and was mechanically identical to the LLY. LLY in 04-05 was 300 hp, then 06-07 the LLY dropped to 250 hp and the LBZ got the 300 hp tune. Basically, LLY was the only 2004.5-2005 engine, then LLY continued alongside the LBZ through 07; the only difference being the tune. The injectors were updated with the LLY/LBZ. The problems weren't as bad, but the big difference is that they were moved outside the valve cover so that labor cost was significantly reduced. One other big change in 04.5 was the use of a Garrett VVT turbo.

Late 07-10 was the LMM. Particulate filter. Eww. MPG dropped from around 20 mpg to 13 at best.

If I were buying one, I'd get an LLY/LBZ, or an LB7 that has had the injector upgrade.

I had an 04 LB7 and an 08 LMM. I dumped the LB7 because it was out of time on the injector warranty with only 80k and I dumped the LMM because I was tired of paying for 13mpg. If I only wanted 13 mpg I could have had a gas engine.

... but I'm currently looking for an LLY/LBZ for a diesel swap.

JMHOH, but people want to call Dodge Cummings trucks as a "great motor in a E36 M3 wrapper". The GM's with a Duramax are a E36 M3 filled Twinkie dipped in E36 M3.

The injectors are a problem, but they aren't that big of a problem, IMO. Just a time consuming job. Be glad you aren't asking about Ford 6.0/6.4's.....

Ranger50 wrote: JMHOH, but people want to call Dodge Cummings trucks as a "great motor in a E36 M3 wrapper". The GM's with a Duramax are a E36 M3 filled Twinkie dipped in E36 M3.

I am not at all sure what that means. Should I buy a E36 M3 truck to get a good motor? Should I give up a good ride to get a "real" truck with a 22yr old International design and twin I beams from the 1930s? Should I be hungry for twinkies? Oh man... I could eat a pile of twinkies.

(LLY with 125k trouble free miles except as noted above and no real loyalty to any brand - just my own observations).

In the oil patch, very few companies buy "fleet" cummins. Only time I've ever saw them is when people get a vehicle allowance. It's either powerjokes or dmaxes, with dmaxes being the lead.

Unless you are pummeling the crap out of the truck, the GM is the way to go. Too many issues with the newer 6.0L/6.4L Ford's, even if their interior is better. If you go all the way back to a 7.3L Ford, they aren't any better (IMO) than a more current GM and the dmax will make moar powa!

Ok, so basically an '05-'06 with the 300hp tune and make sure it's up on maintenance/injectors.

I live in Colorado, so rust isn't an issue and there are alot of trucks here to choose from.

Any option packages that I should try to get? I know I want the tow package, but are any others must haves?

docwyte wrote: Any option packages that I should try to get? I know I want the tow package, but are any others must haves?

The one with power leather heated seats, climate control, and the unlimited Sirius/XM radio makes for a comfortable place to pull race cars around. The rear seats fold down on mine (like a wagon) and it is awesome. Not sure if it is standard - if not you def want it.

Rear LSD is not standard - so try to find one with it on the option sheet. It is very helpful in light snow or gravel when the truck is empty but you don't want to be in 4WD. Diesels make a lot of torque (obviously) and wheelspin can surprise you even on a rain slicked road at moderate speeds. Ya hit a bump, bounce the rear light and wheeee!

The Ford 6.0's aren't a problem if maintained properly, much like any other engine.

I've been shopping diesel trucks for 6 months now and still haven't picked one. Too many options. I really don't think there are any truly bad choices, just different things to consider for each model.

Giant Purple Snorklewacker wrote:

docwyte wrote: Any option packages that I should try to get? I know I want the tow package, but are any others must haves?

The one with power leather heated seats, climate control, and the unlimited Sirius/XM radio makes for a comfortable place to pull race cars around. The rear seats fold down on mine (like a wagon) and it is awesome. Not sure if it is standard - if not you def want it. Rear LSD is not standard - so try to find one with it on the option sheet. It is very helpful in light snow or gravel when the truck is empty but you don't want to be in 4WD. Diesels make a lot of torque (obviously) and wheelspin can surprise you even on a rain slicked road at moderate speeds. Ya hit a bump, bounce the rear light and wheeee!

I'm going to go a slightly different way. Both of mine had top-o-the line packages, leather, heated, sirius, onstar, the works. I didn't have the 08 long enough for anything to fail, but the 04 had some fun little issues. No matter what you were listening to on the radio when you shut the truck off, it would always play track 1 of disc 3 in the changer when you started it up. That happened about the same time the steering wheel controller buttons quit working. I fixed the buttons, but it still always played disc three. The power seat heaters had a bad relay and would only stay on for about three minutes before the relay overheated and quit.

It wasn't a lemon by any means, but I bought a luxury truck and I expected the luxuries to work. If I were doing a GM again I would get minimal options; PW, PL, cloth seats, single CD.

DaveEstey wrote: The Ford 6.0's aren't a problem if maintained properly, much like any other engine.

Some of the problems with the 6.0 aren't maintenance issues. The EGR coolers are known to blow a leak, at which point you either just start blowing crazy smoke and overheat (if you're lucky) If you happen to shut down and try to restart, you hydrolock the engine and turn it into a pile of scrap.

Oil coolers are consistent failure points too.

There are aftermarket solutions for all of the 6.0L issues, but they're expensive, and I just don't feel like I should have to do them with the wide array of other diesels out there.

When I set out to buy my latest diesel, I had my choice of darn near anything; 6.5, 7.3, 6.0, 5.9, dmax... and I chose this: a 99 E350 7.3L cargo van. This thing doesn't have anything except a posi rear. No tilt, no cruise, no tape deck, no CD, two pathetic speakers, rubber floors, bare steel walls, and I love it. Nothing extraneous to fail. If I want good tunes I can add a good stereo. If I want carpet I can add it. If I want 500hp, I just spend a lot of money.

I am not at all sure what that means. Should I buy a E36 M3 truck to get a good motor? Should I give up a good ride to get a "real" truck with a 22yr old International design and twin I beams from the 1930s? Should I be hungry for twinkies? Oh man... I could eat a pile of twinkies.

I like this response. Twin I beams suck.

curtis73 wrote:

Giant Purple Snorklewacker wrote:

docwyte wrote: Any option packages that I should try to get? I know I want the tow package, but are any others must haves?

The one with power leather heated seats, climate control, and the unlimited Sirius/XM radio makes for a comfortable place to pull race cars around. The rear seats fold down on mine (like a wagon) and it is awesome. Not sure if it is standard - if not you def want it. Rear LSD is not standard - so try to find one with it on the option sheet. It is very helpful in light snow or gravel when the truck is empty but you don't want to be in 4WD. Diesels make a lot of torque (obviously) and wheelspin can surprise you even on a rain slicked road at moderate speeds. Ya hit a bump, bounce the rear light and wheeee!

I'm going to go a slightly different way. Both of mine had top-o-the line packages, leather, heated, sirius, onstar, the works. I didn't have the 08 long enough for anything to fail, but the 04 had some fun little issues. No matter what you were listening to on the radio when you shut the truck off, it would always play track 1 of disc 3 in the changer when you started it up. That happened about the same time the steering wheel controller buttons quit working. I fixed the buttons, but it still always played disc three. The power seat heaters had a bad relay and would only stay on for about three minutes before the relay overheated and quit. It wasn't a lemon by any means, but I bought a luxury truck and I expected the luxuries to work. If I were doing a GM again I would get minimal options; PW, PL, cloth seats, single CD.

My SO had an 06 F350 with the 6.0 and worked it hard hauling horse trailers for 80k miles without skipping a beat, and she's not what I would call maintenance inclined. The bad stories get repeated over and over, the good stories get told once.

Bringing this back. How can you tell whether the truck has an LLY or LBZ motor?

docwyte wrote: Bringing this back. How can you tell whether the truck has an LLY or LBZ motor?

8th digit of the VIN 1 = LB7, 2 = LLY, D = LBZ

Thanks!

docwyte wrote: May be in the market for a Duramax 2500. Want a quad cab, 4 wheel drive, short bed. A quick craigslist search yields quite a few in the '03-'05 year range with 100k ish miles for +/- $15k. What should I be looking for and what years are more desirable? What maintenance should I specifically be looking to be done with around that mileage? Which year did Chevy put in the 6 speed Allison tranny? Truck will be used to haul my race car/trailer, house projects and may be turned into a daily-ish driver.

I didn't know Duramax made trucks.

iceracer wrote: I didn't know Duramax made trucks.

Isuzu has always made trucks

I really like my 95 Cummins dually BUT I bought it because it was cheap to buy, cheap to modify, and easy to work on. Had I been willing to spend more money on a truck I would have looked hard at the newer duramax trucks with the allison trans....real nice trucks.

Cummins builds trucks too ?

I bought a 03 in 05, it was a factory buy back with 14000 on it. PO bought it to tow a camper and had it back to the dealer over an over due to what he called a ligh front end. I know exactly what he meant, you get good weight on and the GM front really unweights. It never let me down and we used the crap out of it, had 67k on it when we traded it for a king ranch.

The duramax with Allison is a pretty good package, all the horror stories are really few and far between just often repeated. Hope you find a good one.

On my 4th Duramax now a 07' Classic with 110k. Pulls my gooseneck great. Never had any mechanical issues with any of them. 07.5-10 Have E36 M3ty mpg due to emissions, supposedly 11+ mpg is back where it should be.

Bought one yesterday! '05 GMX 2500 Duramax, crew cab, SLT, short bed. Rear limited slip diff, all the goodies, extendable mirrors, trailer brake controller, very pricey topper (which I'll most likely sell), bed liner. Victory Red, 113k miles on it, all stock.

Bought it from a retired engineer, who's the epitome of anal. Records showing oil changes every 3000 miles, had the original window sticker, etc, etc. All fluids have been flushed except the brakes. He had some weird bias about that, so I'll do them.

Will need tires in the fall, everything else is good. Got it for a decent price, especially considering all the other trucks were either on 6" lifts, had more mileage, or were at dealers asking absurd prices.