2005 GMC Sierra
 

Hello
Im looking to get a 99-06 GMC/Chevy rc/sb truck. I found one im really interested in, its a 2005 GMC sierra with 4.8L and a manual. The question i have is what trans come in the manual trucks and how strong are they as i plan to nitrous the truck then go turbo when i build a new motor.

i think it would be a nv3500 in that truck. power wise not soo much. maybe 450-500hp max

Yes that's the nv3500 in that truck. It is rated at 310ft lbs. That stock 4.8L is IIRC 284ft lbs at max torque (roughly 4400-6000 rpms). There is the nv4500 that comes in the 2500 Silverado/sierra behind the 6.0. It is rated at about 440ft lbs. The nv4500 will bolt right up in place of the nv3500 and is an easy swap, (or so ive read). The nv4500 has a granny gear 1st. The full ton/3500 that came with a 6.6L diesel or 8.1gas came with a nv5600, which is rated at 550ft lbs. There are people who say they run turbo 5.3s over 500ft lbs on the nv3500. There are many who also swap to a car transmission, if you don't plan to tow.