I will be coming back to the states here soon and am planning on getting me a 05 duramax 2500 I want to throw some minor performance parts on it such as exhaust, intake and possibly throw in a engine programmer but I was reading on the Allison tranny and on the 05 it was saying the torque capacity is only 565ft lbs.. but doesn't it come stock with 605 ft lbs? What I am trying to do with it is just put some good performance upgrades without having to buy a new tranny and being within a safe range... Thanks for the help!

I'd start by checking out the differences in each year. The HP/torque specs changed over the years depending on the engine and tune - LBZ/LLY, etc. I think there's a 'sticky' on one of the other forums that explains it.

I believe the LBZs have the highest stock numbers (at least pre-DPF). If it were me I'd be looking for one of those. I think 06 and earlyi 07 is your best bet.

As for gadgets and add-ons there're pretty much an infinite number of things to do. IMO a chip and some exhaust work will get you the most bang for your buck to start with.

LLY specs

6.6 L LLY Specifications:


Configuration: V8
Displacement: 403 cubic inches, 6.6 liters
Compression Ratio: 17.5:1 (16.8:1 in 2006)
Bore: 4.06 inches
Stroke: 3.90 inches
Aspiration: Turbocharged w/ intercooler
Valvetrain: OHV, 4 valves per cylinder
Oil Capacity: 10 quarts w/filter
Weight: approx. 835 lbs
*Horsepower: 310 hp @ 3,000 RPM
320 hp @ 3,000 RPM in 2006

*Torque: 520 lb-ft @ 1,600 RPM
560 lb-ft @ 1,600 RPM in 2006

LLY specs

6.6 L LLY Specifications:


Configuration: V8
Displacement: 403 cubic inches, 6.6 liters
Compression Ratio: 17.5:1 (16.8:1 in 2006)
Bore: 4.06 inches
Stroke: 3.90 inches
Aspiration: Turbocharged w/ intercooler
Valvetrain: OHV, 4 valves per cylinder
Oil Capacity: 10 quarts w/filter
Weight: approx. 835 lbs
*Horsepower: 310 hp @ 3,000 RPM
320 hp @ 3,000 RPM in 2006

*Torque: 520 lb-ft @ 1,600 RPM
560 lb-ft @ 1,600 RPM in 2006
X2 And those are FWHP#'s not RWHP#'s And bnewman77 welcome to DP I see you must know alittle because you brought up torque capacity. Thats what kills the Allison. Looks to me the stock LLY is making about 260-270 RWHP... with maybe 510 RWTQ This? should be at Duramax Second Generation: 2004.5-2005 (LLY)