My friend just bought a 2006 2500HD with 2300 miles. He brought it over to show me the truck and he let me drive it. The truck has the 6.0L in it and a 4.10 gear. The truck was so slow and felt under powered. My stock 2002 Yukon would kill it. Everyone says to do a 6.0L swap to your truck to make it go good and this is why I am gettting ready to do so in mine. However this truck is so numb it scares me to do so. How much power is this motor rated at? How can I tell if it is the LQ4 or LQ9? If I were to put his motor in my truck with a LPE GT2=3 cam would it really be that much faster than my 5.3L?

 

My 2500HD wasn't stock for long but I don't remember feeling like it was underpowered

 

I have A 5 speed 2500, I thought the same thing till I got my hands on the hp software. The lq4 6.0 is rated at 467 tq but you only get 70% of that past 4500RPM at WOT. Get hp or a tune and remove TM, and adjust tq app tables

 

Alright thanks for the suggestion. This truck really needs some mods!

 

Two words...Torque Management (TM). The computer (PCM) does alot of things to remove power output from the engine if you mash the gas from a stop or shift gears. I'm not familiar with PCM tuning but there are alot of people here who can help answer some questions. I'm pretty sure HD truck TM is worse than 1/2 ton trucks. HD trucks also weigh alot more compared to 1/2 ton trucks.

 

Lets see. It's a heavy *** truck, the 4L80E has a huge 1st gear ratio(55-60 mph before it shifts to 2nd at WOT), and torque management kills it. I had an 03 HD with an CAI, exhaust, E-fans, and custom tune and those seemed to help quite a bit. If I still had it, I would've put a Maggie on it.

 

Damn, what 6.0 do you have from the factory that has 467tq? How about like 360tq from a standard LQ4.

 

Yea the suck, I have same truck... 04 2500 crew cab, 4x4. 4:10 gears... it take for ever to get it out of first, and you might as well forget about ever doing a burnout, However i have noticed the more miles.. (im to 6,000 now the better it runs.

We put 700 on yesterday pulling 8K pound. It averaged 9.4 mpg and our average speed was 75 mph which means we where really rolling 80+.

The Trucks are just set up to pull, I have also been told to delete them TM as well...

Next time you drive get on the free way, once the trucks are out of a first they run good in second then 3ed is the power gear or so it feels.. My 60-99 is quicker than the 0-60 which sucks cause how often do you get to go 99

 

03 just going by what the hp tables said take a closer look max avilible tq is 467

 

Its the TQ management. I have a 04 5.3 and it my GFs Saturn beats it I can feel the PCM kill the power. It wont hardly even spin the tires in dirt