I'm looking at a 3500 dually. It's a 2004.5 LLY second gen Duramax. I'd be interested to hear from anyone who has experience with these motors, known problems, issues, fixes mods etc.
I read that it has 590tq 310hp. Is this correct ? The truck has 3:73 gears...Did all of these trucks have the Allison tranny ? Any help would be greatly appreciated.

Great great trucks! no real known problems, some had injector that needed to be changed, once done, you're ok. Yes they all had the well known Allison transmission (5 speed in those years), way more fuel efficient than his 2 others competitors, you can't go wrong for sure but as for any brand, get an inspection done before buying! Good luck!

Just buy one already!!

Good to meet you and the family last night. Definately need to do that again sometime, but not on a school night.

I am pretty sure the Allison is an option and not automatically included with the diesel

Allison 5 spd auto or ZF 6 spd manual are/were only two choices.

try buying an 06' or 07' ,gm made alot of changes[like 6spd allison,32 bit computer,larger redesigned cooling sys,stronger eng block and insides]try going to dieselplace . com,,theres lots of info and alot of great info

what about capacity? I have been around looking for one as well and have similar weight boat. Today I even went to the GMC dealer and asked them, no answer. I have also posted on dieselplace.com, again no anwer. If you have a 5th wheel trailer then everybody got answers. If you have a weight distributing hitch, more answers but a lot of variations. I like to trade in the Suburban I got for a dually, but until I can see that a dually will tow my boat legally I'm holding off. Anybody know something worth knowing with respect to this?

in GM brochures it is written. up to 15 k no problem, it's been this rating for over...5 years let'S say.

it's not 15k on a non wt distributing ball .. it's 11.500

ps the dually tows much much better than the suburban