What to look for in a used dmax

[1996 Yukon]

This isnt for me but my dad is looking at buying a used duramax. he wants to get a regular cab either short or long bed it doesnt really matter. but back to the point what are some things me and him should be looking at when we go to buy a new used one? he wants an 04+ and im familiar with cars and all but i have NO experience with diesels. any input will be greatfully appreciated

[foreman00081]

do a search, you should get a pretty good amount of info but your best bet is to go read up at www.dieselplace.com because its a whole forum dedicated to GM diesel trucks, and with over 60000 memebers theres a ton of good stuff to research, and heres a couple of my replies to similar questions, im just going to copy and paste them cause im too lazy to write up a big thing now, hope it helps:
as far as what year its pretty much your call, the 01-03's (LB7) did have injector issues but they are warrentied up to 200k miles by GM, mine are still original at 108k and no problems yet. some of the LLY's (04-05) did have some overheating issues but im pretty sure thats all been fixed by now. the LBZ's (05-07) i dont know a ton about but im pretty sure they were the first years with the variable turbo which gave it more power. the newest generation is the LMM which i believe is just about the same as the LBZ but with a little more power and the new emmissions standards including the DPF in the exhaust. and as far as reliability goes they are holding up very well, theres plenty of dmax's with 300K+ out there, ive personally seen a couple and even seen one with over 500k on the clock...

look for injector issues from 01-03, get the vin and have it checked to see if they have been replaced. they are warrentied up to 200k so if they havent been done yet its not a huge deal, mine are original as far as i can tell on my 03, 107K miles and it runs like brand new. you can check for white smoke out of the tailpipe, less than normal power is also an indicator and fuel in the oil is a definite sign of bad injectors. other than that i dont think there are really a whole lot of other things to look for except the normal used truck stuff. if you can it would be good to find out how the truck was used and if it was run stock or with a programmer cause depending on what programmer was used could mean possible tranny issues.

[Lifsvr7]

I was wondering the same things... thanks

[1996 Yukon]

yeah his friends 03 2500 HD with the 6.6 had injector issues too. but mostly 01-03 d-max's have injetor problems right?

['96 Z-71]

'01-04's had the most problems. Halfway through '04 they came out with the LLY engine and that has a different injector set-up which is more reliable but you'll still hear of some people replacing them once in a while.

[foreman00081]

ya, they fixed the problem with the injectors and after 03 it wasnt a problem anymore. and GM did extend the warrenty on 01-03 dmax's to cover the injectors to 200k miles....

[sport91]

What years had th ejump in HP and torque?

[justy]

LB7 Power / Torque: 300 hp (220 kW) @ 3,100 rpm / 520 ft·lbf (705 N·m) @ 1,800 rpm. (2001)

LLY Power / Torque: 310 hp (231 kW) @ 3,000 rpm / 590 ft·lbf (800 N·m) @ 1,800 rpm. (2004)

LBZ Power / Torque: 360 hp (268 kW) @ 3,200 rpm / 650 ft·lbf (881 N·m) @ 1,600 rpm. (2006)

LMM Power / Torque: 365 hp (272 kW) @ 3,200 rpm / 660 ft·lbf (895 N·m) @ 1,600 rpm. (2007.5)

New 4.5 L V8 310 hp (231 kW) and 520 ft·lbf (705 N·m) of torque. (2009)

I maybe off some.

[Lifsvr7]

I didn't realize that the LBZ was that big of a jump in HP/torque

[justy]

Yup big difference.

But if you drive a LBZ or a LMM I can't tell much difference between the two. The LMM maybe a little faster off line if you got a camper or something behind lol.