mine went out at 60k when my truck was bone stock. which it didnt surprise me. guys at aamco said it was cheap taiwan made bearings that make them go.

 

The one in my 2005 Av with a stock 5.3 (and I mean stock... wife won't even let me get in with the laptop in my hand...) is already slipping. 14k miles...

 

knocking on wood with one hand as I type with the other...wait a minute...that didn't sound right...
anywho...
I'm about to roll over 200k with original 4L60e...shift kit installed w/ ProCharger @ 70K...Royal Purple dialysis @ 150K...TB verter @ 199K...new best of 13.59 two weeks ago @ 4930 #'s...I have servo's waiting to be installed...
not sure on the current HP...pushing 10-12 #'s of boost...and dare I say on the original motor...

 

'03 5.3 Cold air/ Superchip / perf. exhaust- FRIED 1st 4l60e at 37k, 2nd at 61k, 3rd at 63k, told the helpless GM dealership to role it out the door and had one built. transgo kit, reverse drum, vette servo, etc. I believe the problem is with the stock shift settings. Chevy likes slow, smooth shifts. These are heatmakers. Time will tell, but reading around the forums it seems that the guys who put in shift kits, corvette servos, and other small modifications do get longer use of their 4l60e. I didn't want to modify the tranny and void the warranty, but CHRIST ALMIGHTY! These things stock are CRAP!

 

STS installed 2 years ago at 30K along with shift kit (softest settings), vette servo and DACCO reman TB stall. 7lbs most of the time, with 10lbs when I feel spunky and just last weekend, turned it up to 11.5lbs and clicked off a 12.79@105.3. Same truck as you, only with a 4.8. 67K on the clock now. No problems

 

how firm are the shifts at that setting? i am going for nearly stock sound and feel other than more power and the wistle.

great ET for the lowly 4.8

 

ive seen a 1500 4.3 L with 16k on it and it

 

I've actually turned them down a bit with EFILive, cuz I like them crisp but not hard at part throttle and then firm at WOT. I think the key to making them live is finding the right balance with the shift to let it slip enough to not break the hard parts, but also not so much where it burns up the clutches.

I told my buddy Chris (thunder550) that I was running a 12 last weekend, or it was coming home on a trailer Was in the 12's 3 passes . It will run low 13 pretty easy on 10 lbs if I launch with 8-10 lbs.

 

I guess its hit or miss with these transmissions.

 

that is kinda funny and you can bet when i blow up the tranny FLT will be fixing it up for me . i am just hoping to get by for a year or so before i need their help.