2001 Tahoe 5.3 4L60E slipping - any help?

I just got a new Topdon obd dongle that can read all the modules including transmission information. I have a whole bunch of TAP cells with pluses and minuses so it appears my 2005 does have adaptives.....I always noticed if I drove very aggressively it would shift better for a while after so I thought I must be going crazy when you said it didn't have adaptives

Unfortunately it also reset my 10,700 engine hours to 1.4 after scanning the instrument cluster :-(

I'm trying to learn what all information I can get and what it means. I've had a couple times where the TCC started pulsing on and off, mostly when it was still cold and I accidentally left it in drive instead of 3rd....it kept locking and unlocking in 4th gear....
 
I run maxlife in my 4l60e's
242k and 237k
Change often all there life
My 2003 has a slow shift nature that is a norm from 2 to 3 but not slip, could this be what you feel ?
 
I run maxlife in my 4l60e's
242k and 237k
Change often all there life
My 2003 has a slow shift nature that is a norm from 2 to 3 but not slip, could this be what you feel ?
No I'm pretty sure it was already into 4th gear and just started unlocking and locking until I put it back into 3rd gear then it stayed locked up, but I did have it happen once in 3rd gear for a few seconds. But by the time I got pids displayed for TCC slip and PWM % it hasn't done it for the whole week, even when I towed a trailer with a yard of gravel (plus the truck normally loaded at around max payload). Towing the trailer it was sitting at around 0 rpm slip on flat ground.
 
I run maxlife in my 4l60e's
242k and 237k
Change often all there life
My 2003 has a slow shift nature that is a norm from 2 to 3 but not slip, could this be what you feel ?
Btw I was planning on running tes-668 or tes-295 fluid on my upcoming change. I have Mobil dex 6 in it now with probably 40-50k on it.
I used maxlife in my TH2004R in my Oldsmobile years ago before I learned it's "low viscosity". I didn't have any issues with it in that transmission despite it being close to 300k miles but I believe it has a shift kit that would have been installed before 100k by the previous owner.
The truck I want something a little higher viscosity since it's not if but when I will wear out this transmission. 265k miles with a lot of stop and go.
 
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Here are the adaptives it's showing. I'm not sure why some are in psi and some in KPA, either way it's mostly adding pressure which makes sense for a high mileage transmission with wear. The shifts are pretty good though I find very light throttle when it gets hot in stop and go can become mushy....heavier throttle it firms up a lot and many times I've noticed it shift more firmly after some harder driving.

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I just got a new Topdon obd dongle that can read all the modules including transmission information. I have a whole bunch of TAP cells with pluses and minuses so it appears my 2005 does have adaptives.....I always noticed if I drove very aggressively it would shift better for a while after so I thought I must be going crazy when you said it didn't have adaptives

Unfortunately it also reset my 10,700 engine hours to 1.4 after scanning the instrument cluster :-(

I'm trying to learn what all information I can get and what it means. I've had a couple times where the TCC started pulsing on and off, mostly when it was still cold and I accidentally left it in drive instead of 3rd....it kept locking and unlocking in 4th gear....

Like I stated in a earlier post.....Without a ISS (Input Speed Sensor), The ECM cannot accurately calculate shift times.
 
Like I stated in a earlier post.....Without a ISS (Input Speed Sensor), The ECM cannot accurately calculate shift times.
I understand that it can't do it accurately, but see my posted screenshots with all the adaptive adjustment tables.... I've been trying to find information on what year this started but haven't found an answer. All I know is it has them for whatever reason and it is a 2005 without iss. The information I did find said it calculates based off vehicle speed and engine RPM.
 
Watch the TCC PWM, Brake Switch, & TCC Enable PID's to diag TCC issue......Could be a hydraulic issue caused by a worn TCC Regulator Valve bore?
That's what I'm trying to watch for, if just hasn't acted up since I got set up to watch them. Is it possible to be a sticky valve instead of worn? Being so intermittent seems less likely to be a worn part...it also used to occasionally start in second gear...like once every couple of months but that went away with a fluid change and didn't occur again until the fluid was at least a couple years old.
 
I understand that it can't do it accurately, but see my posted screenshots with all the adaptive adjustment tables.... I've been trying to find information on what year this started but haven't found an answer. All I know is it has them for whatever reason and it is a 2005 without iss. The information I did find said it calculates based off vehicle speed and engine RPM.

4L60E/4L65E didn't get adaptive's 'til the GMT900 when a ISS was added, The only GMT800's to have adaptive strategy are Allison 1000 equipped trucks.

4T65E FWD vehicles did have adaptive's.

Here's a file from a '05 Tahoe & a '08 Tahoe., Note that the '08 has a Adapt tap.

dvBRk7k.png

lMiKZTi.png
 
That's what I'm trying to watch for, if just hasn't acted up since I got set up to watch them. Is it possible to be a sticky valve instead of worn? Being so intermittent seems less likely to be a worn part...it also used to occasionally start in second gear...like once every couple of months but that went away with a fluid change and didn't occur again until the fluid was at least a couple years old.

The TCC Regulator Valve can do funny things 'til you lose lock-up all together.
 
4L60E/4L65E didn't get adaptive's 'til the GMT900 when a ISS was added, The only GMT800's to have adaptive strategy are Allison 1000 equipped trucks.

4T65E FWD vehicles did have adaptive's.

Here's a file from a '05 Tahoe & a '08 Tahoe., Note that the '08 has a Adapt tap.

dvBRk7k.png

lMiKZTi.png
So once again...what are those screenshots I posted above? I asked a similar question on ls1.com in the trans forum and so far the only reply was that they had it long before that... someone had to tune it out of his 95 ss after it lowered the pressure down from his shift kit installation within a few days.
 
If GMT800's were able to lower pressure & nullify a larger Boost Valve.....It would be all over the internet.

The TAP/Shift Error values will still populate, But that doesn't mean it affects shift pressures. The same basic hardware is used for all Electronic GM A4 units....Then it's calibrated to the specific unit....4T65E, 4T80E, 4T45E, 4L80E, & 4L60E & it's derivative's.

GM's own service information is confusing leading one to believe that TAP strategy is part of every calibration.

I've spent a lot of time in the trenches with 4L60E's in particular....They shift sloppy because they're built sloppily from the factory, I know you have a mile of 2/4 Band clearance & the 3/4 Clutch is likely plenty loose by now.
 
Knock on wood my 2012 4L "Slippy" is still doing fine but it gets regular fluid changes w/filter and it's only V-6 powered with the old timer 4.3 motor. Good luck with yours. I've heard they're pretty good as long as they're maintained.
 
Knock on wood my 2012 4L "Slippy" is still doing fine but it gets regular fluid changes w/filter and it's only V-6 powered with the old timer 4.3 motor. Good luck with yours. I've heard they're pretty good as long as they're maintained.
Mine wasn't maintained well by my employer other than oil changes until I bought it. I changed the transmission fluid at 192k miles and it may have been original. I don't know that it wasn't changed at like 80k miles though. It isn't really sloppy, especially at heavier throttle it shifts pretty crisp. It's just at light throttle when hot. It has occasional second gear starts that happened once every couple months and that stopped happening after I changed the fluid.
We didn't have any 4L60E fail in the fleet where I work. 5 in total, one being a 2013 which still ran great when it got replaced by a 2017 which needed the 6L80E replaced at like 140k miles and a 10 speed 2018 ford f150 10 speed failed at 55k miles.
However none of the fleet has ever had 265k miles until I bought the 2005 and kept fixing it up instead of replacing it.
 
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