2003 Tahoe Rwd -4l60E Questiones! Trouble Shooting

[GrumpyBstrd4L6LS1]

2 weeks ago out of nowhere my truck goes into what feels like neutral ,but Scanner says its in 3rd , story is 2018 I installed a aTransgo sk shit kit and Pinless Forward Accumulator Piston Kit by Sonnax and Transgo 4L652ACM Transmission Piston, 1-2 Accumulator , it was great till 2 weeks ago, I hooked up transmission pressure gauge all readings seem good lifted vehicle and went thru all the gears pressure readings idle 75-220 wot and in all gears around 175-160 all seems normal there disconnected trans harness and same 1 and 2 second gear ok reverse ok but seems like it still goes into nuetral or is it really slipping ? The pcm should give a dam fault for a Slipping/gear monitoring smh! Vss? Tcc? O-Ring in valve body? Stuct 2-3 shift valve / shuttle valve ! Harness corrosion! I have read articles where they have rebuilt the transnsmission with new , just about all and still the problems checked and disconnected fuses still goes into 2nd and 1st , I am gonna check harnness and connectors next the transmission harness looks like it a tiny tiny bit of oil coming thru, also shouldnt the signal from the vss/tps and abs trigger a fault in the pcm

 

[GrumpyBstrd4L6LS1]

2 weeks ago out of nowhere my truck goes into what feels like neutral ,but Scanner says its in 3rd , story is 2018 I installed a aTransgo sk shit kit and Pinless Forward Accumulator Piston Kit by Sonnax and Transgo 4L652ACM Transmission Piston, 1-2 Accumulator , it was great till 2 weeks ago, I hooked up transmission pressure gauge all readings seem good lifted vehicle and went thru all the gears pressure readings idle 75-220 wot and in all gears around 175-160 all seems normal there disconnected trans harness and same 1 and 2 second gear ok reverse ok but seems like it still goes into nuetral or is it really slipping ? The pcm should give a dam fault for a Slipping/gear monitoring smh! Vss? Tcc? O-Ring in valve body? Stuct 2-3 shift valve / shuttle valve ! Harness corrosion! I have read articles where they have rebuilt the transnsmission with new , just about all and still the problems checked and disconnected fuses still goes into 2nd and 1st , I am gonna check harnness and connectors next the transmission harness looks like it a tiny tiny bit of oil coming thru, also shouldnt the signal from the vss/tps and abs trigger a fault in the pcm, possible capillary leak, also but not convinced its just that , need to check solenoids and O-Rings and if there is a burnt smell and debris in trans pan ! Oh well have a good weekend everbody!

 

[Sam Harris]

Do you have a scanner? Preferably a Tech 2, or another bi-directional one would be good. How about reverse? Does it work normally, or same as 3rd gear?

 

[rockola1971]

Check your fluid! Is it burnt? Smell burnt? Is it anything other than bright pink? Have floaters in it when put on a white piece of paper? If it is burnt then you likely burnt up the 3-4 clutch pack. Might have to drop the pan if the fluid doesnt pass the pink test. The evidence will then be laying in the bottom of your pan and it will stick out like a sore thumb.

 

[GrumpyBstrd4L6LS1]

Do you have a scanner? Preferably a Tech 2, or another bi-directional one would be good. How about reverse? Does it work normally, or same as 3rd gear?

Reverse is good , I have a scanner a Autel I need to read up on how the tps and vss and tcc and pcm all communicate , I at first thought my second gear was slipping when it first happened but I drove it again and it is 3rd gear when it feels like it goes into neutral / starts slipping , I had thr scanner on it for a little bit and was checking solenoids A and B both were off , when it happens but I am gonna recheck my mph , Im also gonna disconnect my VSS and see what happens I already disconnected the harness at the transmission connector next is checking the harness route and at the pcm connector . Thanks

 

[Mudsport96]

How did the separator plate look when you replace things in 2018? Ive had 4l60e plates blow the check balls through causing a no engagement issue. I ALWAYS replace the plate when i do any work that requires pulling the valvebody.

 

[rockola1971]

How did the separator plate look when you replace things in 2018? Ive had 4l60e plates blow the check balls through causing a no engagement issue. I ALWAYS replace the plate when i do any work that requires pulling the valvebody.

Good point. He very well could have a separator plate that banged a check ball into its seat and is stuck or went all the way through.

 

[Mudsport96]

Good point. He very well could have a separator plate that banged a check ball into its seat and is stuck or went all the way through.

And if it is the original at 20 years old, it very well could be. That is why i brought it up since he isnt getting codes, it has to be a mechanical failure.