2004 4.8 Silverado Won't turn over 650 rpms with brakes applied

2004 Silverado
4.8/4L60E
Bone Stock

As stated when trying to powerbrake the truck will not go above 650 rpm when trying to powerbrake it. It acts like a traction assist system is activating very similar to what a pontiac solstice does if you've ever driven on of those. Ive never seen a gen 3 truck do this before. There is no traction assist button in the truck to turn off but even if there was I wouldn't think it it would hold the truck back this bad. Its throwing no ses lights but it literately will not get out of the way of itself until it hits about 20 mph then it will start to pull but by that time my dads Caravan would have put 4 lengths on it. lol



Anyone have any ideals?

Attaching a scan an the stock tune. Nothing special in there I've found

If a Gen III doesn't have a Traction control button, it will have traction control all the time, you just don't have the ability to shut it off. I looked at your tune and your's is still on, look under Engine>tq management> general. Far right is the traction control options. Chances are though, you won't get your rpm's up too much while power braking unless you have a lot more HP than stock or your tires are on slick or gravel-like surface. It's taken me a long time (a lot of work with timing) to get my V-maxx (mostly stock except cold air and exhaust and cat-less) to brake them loose, but even then, it won't go into a full blown burn out without some help with the road surface, but then again i have "32 all terrain tires too. Take a look at your Burst knock too, that generally gives people that "power-band tip-in" people feel around 20 mph. My advice..... get rid of it, check for knock when hammering throttle, if there is none, leave it off. Oh, and i noticed all your tq management and abuse modes are still on. Don't be scared, shut that crap off!

Setting the ETC TPS MAX to 100% for all cells will help alot, it's holding it back a ton right now.

Lots of other things can be changed to make it actually fun to drive.

I have a nearly 100% stock 06 sierra with some changes and it moves out pretty good. PM me and I can send ya the file and you can compare some stuff and see if you like the changes. Nothing I did should affect the driveability or health of the motor/trans.

This was the stock pulled tune. But come to find out it was a transmission problem customer just bought the truck yesterday an took it to a shop today an they informed they had that truck for 2 weeks fixing problems an told the previous owner the transmission had problems but he opted not to fix it an just sold it. New tranny is going in this weekend.

So I have a 2006 Silverado SS that does have traction assist, my button did not work and have a new one on order but no sign of shipping yet. My question is can you tune the traction assist/ traction control out on the Gen 3? Do I have to change the ecm/ecu to a different truck ecu? Truck is rwd only, 6.0 LQ9, 4l65e, Has been tuned but when traction control kicks in the truck is dead for 5 seconds then all power comes back at once. Really sucks when it happens in traffic. Thank you for looking.

Do what I said in post 3. Also in the abuse settings change them to 8,000rpm and 0mph. See what that does.