2003 sierra transmission question

[Currency]

I just thought I would ask, It's not my truck but is my oldest brothers. I've driven it a few time and man is it a sweet sports truck.

It has many mods done to the stock 5300 and has had upgrades in the tune of $4,800 to the transmission but I don't have the exact details on it.

The problem. Powerful motor with a somewhat stock trans with OD. He's had it for about a year I believe, Has blown apart five pumps in the transmission at a cost of around $600 min to replace it each time.

Does anyone know what could be causing this?

I was told this is what happens.

Running in OD on the auto trans around 100mph and when it hits shut off time it drops it back into drive and POWWW. Blows the pump apart.

My brother loves to get attention and show off, If I still had my friends cam I would post pictures of his truck. Blue, dual cowl intake scoop, corvette exhaust with four tips centered in the back coming out of the roll pan and SPL triple electric fans. I think that's all correct. Oh, regular cab short bed. He also has an 2002 jeep grand cherokee and I think it's a 2003 yamaha 700R GYTR that is either pulled behind the jeep or sits in the back of the sports truck.

I want the truck

 

[Rick]

If he wants to run the truck like that maybe he needs to invest in some aftermarket transmission goodies. Namely upgraded pump gears.

Could also try locking out the OD when he's making a high speed pass and see if it holds up.

 

[MrShorty]

4L60E or 4L65E (I'm just not sure when the 65E came out).

I have heard claims that the 4L60E can be rebuilt to withstand a lot. If the transmission is still "somewhat stock", I haven't done any research along those lines myself, but maybe some more research would tell what needs done to get the pump built up.

Or maybe he needs to look into swapping in a 4L80E.

 

[shadowless127]

4L60E or 4L65E (I'm just not sure when the 65E came out).

I have heard claims that the 4L60E can be rebuilt to withstand a lot. If the transmission is still "somewhat stock", I haven't done any research along those lines myself, but maybe some more research would tell what needs done to get the pump built up.

Or maybe he needs to look into swapping in a 4L80E.

this.

a 4L80E would be his best bet if he continues driving like that.

 

[corkey]

get that electronic trans out of there and go with a t-400 , it will handle all the power he can give it, and than some,

 

[james t]

get that electronic trans out of there and go with a t-400 , it will handle all the power he can give it, and than some,

No need to lose overdrive, you can build a 60 to handle alot of abuse and an 80 to handle more power than the 5.3 will ever make, forced induction or otherwise.

I dont really understand... he has $4800 in the tranny but its still fairly stock? You can build a pair of killer 4L60e's for that price.