3rd gear issues. Any thoughts before i find a local Tranny Shop.

[usar17]

Read thru the sticky posts already. 1994 4l60e transmission with corvette servo. Rebuilt it over last winter, finally dropped it in this fall and have been driving the truck the past 2 months. Other day was coming home when 3rd gear sent the RPMs up. Parked it for a few weeks while too busy to mess with it. Today I plugged my laptop in to run stats while driving it. 1st and 2nd gears work fine, solenoids are both working. PCM will command 3rd at around 25MPG, turns off both solenoids, then the rpms go up to about 2.5k. Truck is still moving and I can increase speed but its only if I push the RPMs closer to 3.5k. No codes are tripping and I cant see any red flags in the tunerpro data. I do not claim to be a great mechanic but I had no problems with the rebuild. replaced all the electronics, seals, clutches, steels, servo, rear planetary, band, and sunshell.

any thoughts?

 

[beardeddummy]

You have no 3rd your clutch clearance is off. Make sure you air check the stem drum and check for warped steel if you want advice on firming third up i can help you. Dont shift kit it. They just make the shift feel firm. You need to firm the shift

 

[usar17]

How would that have changed? Theres 200 miles on this transmission with perfect shifts till now

-Shawn
1985 Chevy k10 w/ 92 TBI, 94 4l60e, 91 NP208

 

[df2x4]

It sounds like slipping to me for sure. Not sure how or why on a rebuild that new, automatic transmissions are black magic to me. Hope it's something easy for your sake, but what you're describing is definitely slipping. I'd find a good local shop ASAP and hope 3rd isn't completely toast.

 

[beardeddummy]

If third has slipped once it might as well be toast did you use the load springs in your stem drum? Were they still good and did you use high energy frictions? Is your plate drilled for more fluid on 2-3 upshift and are you using the 3rd gear accumulator or is it blocked? What kind of load have you had on it if you use green grease for your check balls and it was cold they may have been stuck. Your paper valve body gaskets may have shifted during assembly.

 

[beardeddummy]

Sorry for ramblings my mind works that way

 

[usar17]

Yes i used the load springs they seemed fine. Used high energy frictions. No i didnt drill it. Using 3rd accumulator no real load. 200 miles and now the balls stick?

-Shawn
1985 Chevy k10 w/ 92 TBI, 94 4l60e, 91 NP208

 

[beardeddummy]

You may need to do something about your plate maybe a new one or bigger balls. Not sure if there is info online but find some info on ot and drill it. How cold is it there

 

[michael hurd]

If you have a 2-3 flare up issue, you may have an issue with the computer.

Read this link by Sonnax:

http://www.sonnax.com/articles/181-4l60-e-flares-on-2-3-shift-now-what

 

[usar17]

Ok finally got around to more tests.

Line pressure:
-60psi idle in P,N,D
-90psi in R idle
-90psi driving in 1st, 2nd
-120psi while slipping 3rd

Unhooked the wiring harness. Line pressure is 210psi and the tranny sounds horrible. Wtf just happened??? I know its suppose to default to max line pressure but it sounds awful.

-Shawn
1985 Chevy k10 w/ 92 TBI, 94 4l60e, 91 NP208