Tranny Slipping

[19stang66]

So I finally got to drive my Stang for the first time this year. I fixed a couple of tranny leaks and replaced the rear axle seals and put new rear end fluid in the differential.

Now my problem. When I shift into reverse or drive I have to rev the engine before the Tranny will engage into whatever gear i'm in. But once I'm up to speed it doesn't slip at all and runs just fine. I never had this problem last year before I stored her. So I'm thinking it has to be something I just did recently.

Could the new rear end fluid make it slip? I used the Royal Purple Synthetic stuff. Could have I screwed something up when I removed the axles and cracked the differential to drain the fluid? I really don't know whats wrong.

 

[enferno]

So I finally got to drive my Stang for the first time this year. I fixed a couple of tranny leaks and replaced the rear axle seals and put new rear end fluid in the differential.

Now my problem. When I shift into reverse or drive I have to rev the engine before the Tranny will engage into whatever gear i'm in. But once I'm up to speed it doesn't slip at all and runs just fine. I never had this problem last year before I stored her. So I'm thinking it has to be something I just did recently.

Could the new rear end fluid make it slip? I used the Royal Purple Synthetic stuff. Could have I screwed something up when I removed the axles and cracked the differential to drain the fluid? I really don't know whats wrong.

did you check your fluid at hot idle to see if it's low or not?

 

[19stang66]

Right after I posted this thread I thought to myself, "Did you ever put in more tranny fluid after you fixed those leaks? Nope you didn't dumbass." I added about 3/4 fluid and she drives perfect now! I even left a lil rubber at the top of the driveway! Pegleg burnouts FTL.

 

[paintballtommy]

anything you did to the rear end shouldnt effect slippage when shiftign the transmission, the rear end is pretty much a completely mechanically driven unit whereas the tranny uses a pump and fluid pressure to get into drive reverse etc
hook up a guage to the test port on your c4 its on the right side of the tranny i believe. wait for it to warm up and check the fluid pressure. use an oil pressure test guage that can read up to a couple hundred psi the test port is a plug right in front of the shift lever on the c4 i beleive. start the car and let it heat up to op temp have a buddy watch the guage and write down the pressures in each gear. hold the brake and shift from park to revers neutral drive 2 and 1 in reverse you should have somewhere between 150 to 180 psi 90-110 in 2 or 1 60-90 in drive and 50-90 in neutral. check each gear while holdign the brake and give it at least 10 seconds in each gear then change gears.
since revers requires such a large amount of pressure to engage correctly if your pump isnt opperating right, normally you will find slippage in reverse before any other gear.

Tom