I saw the GMC C4500 Duramax pulling a giant race boat. This was a big a$$ truck and was wondering if this was the standard 6.6L Duramax. The tranny the same? Just wondering. SPICER

Yea, the engine and transmission in the 4500 and 5500 is the same as the one that come in our trucks. But I do believe that they stayed with the 300/520. It maybe the LLY though.Edited by: hdmax

The C4500 with Duramax engines are all over the place on SoCal freeways as tow trucks. Edited by: OC_DMAX

very nice truck. Duramax also has a 7800 series in larger trucks.its cool to....

Thanks for the reply. Sure makes you think about how OVERpowered we are for hauling kids and birthday presents! The fuel economy alone is reason enough to get a Duramax over a gasser. SPICER

hauling kids and birthday presents? I am not at all overpowered to pull my horse trailer. To haul much more would take either a chip or a lower rearend... which the 4500/5500's have.

I thought the 4500's or maybe the 5500's had the 2000 series Allison instead of the 1000 series found in the pickups?


There's a member who's got a 4500, perhaps he'll chime in about it.

I have heard that it is the same transmission and engine as those found in the 2500HD and 3500 series trucks.

Wait until they have the K version... I've seen just a handful, but for the wreckers/haulers, it may be a good option to get around in the winter.


Looks like just a straight axle configuration. Sure hangs down there though.

Well I just answered my own question by visiting the GMC and Bowtie web sites.


Everything through 5500's have the 1000 series Allison, but all the new Vocational transmission models are listed. Got to go to 6500's to get the 2000 series Ally.


The engine options include a less powerful version of the Dmax that's been listed for some commercial applications in the past, as well as the LLY emission complient engine with LB7 power levels whether you get the Ally or the ZF.


Couldn't find anything on the 4x4 option, but I know I've seen pics of them and a few blurbs in the advertising for wreckers etc, but nothing on the web sites yet.