hello my name is jake and i have a 2001 gmc sierra z71 with a 5.3l. ok so heres the story, today i was driving home and when i gave it gas (not w.o.t) i noticed that the rpms would go up but i wouldnt accelerate. so i pulled off onto a side road and the same thing happened. anyways long story short 1st and 2nd gear work fine but third and drive dont. im 17 and dont really know anything about transmissions but im guessing that ill be needing new one. so where is a good place to get a replacement or is there anything that i can do to fix this one? any help is appreciated.

 

performabuilt and finish line trans>>>sponsors over there. sounds like your trans is slipping, your gonna need a rebuild or buy a new, built one from a sponsor? are there any mods or future mods to the truck?

 

Jake - A good way for you and your truck to get acquainted. Unfortunately, not cheap.

Here is a good link to common problems with 4l60 automatics.

FYI 4L60E common problems / failures | GM Truck Headquarters

Sounds like the 3-4 clutch pack.

The best option as I've been researching replacement transmissions recently might be a "SERTA" or GM Remanufactured Service replacement. They cost about the same as aftermarket, but come with a nationwide 3 yr/100k warranty. The 4L65e is basically a mildly upgraded stock unit.

As others have stated, if you plan on modifying the truck down the road, a hopped up rebuild from a sponsor could be another option. Generally you can upgrade the hard parts as needed.

For a mild street truck...

Trans-Go Shift Kit
Upgraded Sun Shell
Beefier clutches in 3-4
Corvette Servo

Good luck and keep the questions coming.

 

hey thanks for the help guys! I am gonna beef it up a little because i wouldnt mind building up the motor in the future. right now all it has is a c.a.i and flowmaster exhaust. But when i get the trans fixed i plan to get a black bear tune. thanks again!

 

I know this might be a little too late, but I had the same issue. I didn't replace the transmission though, because it was shift from 1 to 2, but not from 2 to 3. I was getting an OBDII code of P0757 and I ended up replacing the shift solenoid(s) that are located inside the transmission with access through the transmission pan. I ended up changing my transmission fluid filter and transmission fluid.

ErnieT in AZ

2002 GMC Sierra 1500 Z71 5.3L
surpassed the 250,000 mile mark

 

sounds like what mine was doing

https://www.performancetrucks.net/fo...-heard-529714/

 

The 3-4 clutch pack will be the first thing to wear out in a "normally driven" truck. How many miles are on it?

Also, if you have to drive the truck manually shift from 1st to 2nd. Avoid "3" and "D". The way a 4L60-E works, if you've lost the 3/4 clutch it will feel like neutral when it tries to shift from 2 to 3 because it's actually going back to first gear without overrun clutch engagement. Not good to let that happen since it can overspin certain parts inside.

 

Thats exactly whats happening with mine. I have 90K on my 4L60, 170K on the Engine, It looses engagement in both 2 and 3 but catches in the higher RMP band but will not shift into 4th. I'm gonna change the ATF first, its brown and smells burnt. I need to find out more info as I take off the pan and check magnet and more but I believe its the clutch packs.

 

I hate to sound negative here, but once any clutch pack or band has slipped to that point it's ruined. Clutches in particular will warp and focus heat unevenly on the high spots leading to more heat, etc. Band disintegrate. Changing the fluid at that point is inadvisable - waste of money actually.