4l60e vette slipping...HELP!!!!

[bkel33]

1999 Corvette 4l60e ls1
Trick flow heads/cam
Stock bottom ls1
Rebuilt 4l60e with yank 3200 converter (just installed)

My car is slipping badly in 3rd and a little when I command 4th on VCM

Transmission was just rebuilt for slippage in 2nd gear (burnt band and drum)
Band, drum, cluthes, steels,pump, converter, seals are all new

I just got the new trans in and went ahead and put a yank 3200 converter in it.

It feels like it's in nuetral when shifting to 3rd


Log and config attached.... PLEASE HELP!!!!!

Brett

[wyochimneysweep]

did you put in new over running clutch and sprag? You build it or someone else?

[bkel33]

I built it. This being my first 4l60 build its possible i did something wrong. I had an issue with the band slipping in 2nd so i replaced the band with wider and got a mew drum. These were the only visibly worn parts but i also did the 3-4 clutches, seals, low reverse piston, accumulator and servo seals, etc while i was in there. I did not replace the sprag. So in short i fixed the second gear issue and somehow broke 3rd

[wyochimneysweep]

did you air check the 3-4 clutch packs for leaks? maybe torn a seal. the kit I put in came with new pistons. Did you have a lip seal tool to help install them? did you soak the clutches in atf before assembly?

[wyochimneysweep]

also you sure about the check balls back in the correct places. Did you clean the vavle body?

[wyochimneysweep]

I'm not a expert but I've done two now in the last 6 months and both are running good. But both I had put in the monster in the box kits. one ss mega and the other was the basic kit.

[bkel33]

did you air check the 3-4 clutch packs for leaks? maybe torn a seal. the kit I put in came with new pistons. Did you have a lip seal tool to help install them? did you soak the clutches in atf before assembly?

I air checked during assembly and seemed fine. I used a "lip wizard" green wheel to install the seals (it came with my kit). I soaked the clutches for about 2 weeks as I was waiting on parts.

[bkel33]

also you sure about the check balls back in the correct places. Did you clean the vavle body?

I thoroughly cleaned the valve body when it was having the 2nd gear issue. I still had the issue when reinstalled so decided to rebuild. This time around I did not disassemble the entire valve body, but did clean it. Check balls were triple checked as well.

I did notice the trans overtemp light came on when I test drove it for about 10 min. I'm not sure if this is because of the new converter or an indication of slipping. 3rd gear does not feel like slipping, it just revs as if in neutral. 4th however slightly engages at about 4500rpm. 1st and 2nd feel perfectly normal.

Sorry for the delayed reply, I just moved and had a lapse in internet.

Sounds like I will be taking it out to have a look ; which isn't simple on the vettes. I was hoping it could be solenoid or valve body related.

I appreciate the help! Any other ideas?

[bkel33]

http://www.hptuners.com/forum/showthread.php?t=37670

Anybody know if this works for the A4? I may try tomorrow!

[wyochimneysweep]

I'll look in my book today and see what's applied in fourth and third. If you get it up to like 5000 rpm with shifter in 2nd and throw it into 4th does it skip 3rd and go into fourth?

[wyochimneysweep]

Looks like if you don't got either third or fourth it's got to be the 3-4 clutch pack bud. That's applied for both and only one that no other gears use. All other clutches that are used are also applied in either first or second

[bkel33]

Looks like if you don't got either third or fourth it's got to be the 3-4 clutch pack bud. That's applied for both and only one that no other gears use. All other clutches that are used are also applied in either first or second

Out it comes! I will take a look inside and update status/pics when possible. Thanks for the help!

[bkel33]

The only other thing I can think that may not be installed properly is the 4 teflon seals on the front shaft. I opted for the solid seals vs. scarf cut and had to make my own tool to get them to shrink back down. Would this cause an issue in 3rd and 4th????

[wyochimneysweep]

Yes that could be the Problem. I paid to have the local tranny shop to Install and size them properly. I wasn't going to take a chance on it. Let us know what u find

[bkel33]

I realize it's been a while since I posted, but just wanted to give an update in the event someone else could use the information.

Trans is shifting great now! I took it all apart, and sure enough 2 of the input shaft teflon seals were damaged. I found wrapping them in electrical tape (sticky side out) and placing the shaft in the freezer helped to resize the rings.

Thanks for the help!