Brand new trans new conveter and NO overdrive

Ok my wife's car 1995 firebird formula had problems with the transmission last year so we decided to change it out. I put in a brand new coverter and a freshly rebuilt 4l60e. Everything works great except overdrive. Upshifts fine and downshifts great, but it's stuck in 3rd and will not go in overdrive. I tried manually shiftinig between 3rd and 4th but it just stays in 3rd. help :banghead:

Well I'm still trying to find out what the problem is, and I've tried adjusting the trans cable, and changed out the coolant temp sensor. All of which i've had not luck. The trans is not bad because it's not slipping and 1st is very strong. Anyone???

the 4L60e is very similar to the 700R4. almost identical actually. I'm not sure what the wiring harness is like on that one (I have a 700R4), but on the 700R4 there is a seperate connector on the driver's side (connector has 4 contact pins on the inside). This controls the torque convertor lockup. if you have that, check to see if it's plugged in properly. it's possible the electrically controlled tranny will refuse 4th gear shift without lockup ability. (I wouldn't say this is incredibly likely.)

Your servos (underneath the large circular cover on the passenger side) actually forces your tranmission to change gear ratio (shift) when fluid is applied to different parts. Since your trans is rebuilt, it's possible they installed the servos incorrectly or did not check for proper clearances. It's not too difficult to install it wrong... there are a handful of plates and washers that stack on top of each other and the order needs to be correct.

Other than that, sounds like you'll have to drop the pan and valve body and have a shop test the solenoids/components are working properly.

btw, if you drop the pan and valve body yourself (which will save $$ and is no more difficult than installing a shift kit - which i wouldn't recommend btw), when you take the bolts out of the valve body make sure you drop it straight down. there are "check balls" or little metal balls that site inside different valleys of the valve body that will fall out if you turn the valve body sideways/vertical. mark the locations of these balls so you can put them back where they came from when you re-install. (or take pictures).

:iagree:

When you purchased your new torque converter, are you sure they sold you one for a tranny with over drive, There is a difference.

Southern

Who did the installation? Was the tranny purchased from them?

how is 2nd gear?????nice and tight,,,,,or somewhat soft????? there is a chance that the pin that retains the 2/4 band is not seated properly,,,pin sometimes pops out when rebuilding...problem is definetly not the converter....other choice would be to remove pan to make sure everything is plugged in,,,you can see the band with pan removed,,,should be relatively tight on drum,,,if sloppy the band is not pinned,,,before you do that,,,would suggest you talk to rebuilder ///supplier for their advice..............

Hmm, do we expect an answer after 2 1/2 years?

You are right Max, got sucked in by the previous post....did not look at the dates....:banghead: