gsdthstr

So this is driving me nuts and I've done all the research I could. Seems like I'm the only person with his problem. 98 gs 400

Wake up in the morning to go to work. Let car warm up. Put in reverse and I get nothing. Have to hold rpms at about 4k for about 30 seconds until reverse catches. Back out of driveway and put in drive, same mess. Have to hold at 4k for about 20-30 second before it goes into gear. In first and second gear car kind of bucks like it's downshifting. Sometimes it happens in 3rd if going up a hill. But cruising it's fine. If car is warm and I park it...say i run to the grocery store, when I come back it goes into reverse and drive just fine. But when it's cold is when I have to hold it at 4k to engage gear. Have drained transmission twice now instead of flushing. Hoping to clear it up slowly but no luck. I'm suspecting valve body but am ready to just say screw it and throw a tranny in it and call it good. But of course saving money never hurts lol . Gonna try power flushing transmission this weekend maybe Monday and give it one last try before i give up. Guess my question is has anybody experienced this??... has anybody had luck replacing just the valve body or shift solenoids?? Thanks In advance for any input.

P.s only code is p0420. Have had this code since the day I bought it

lexo98

iTrader: (2)

On my 300 when I drained and refilled the trans once the car started slipping. When I had it flushed by a shop I was laughing asking why I put motor oil in there. I only used the OE red fluid. Old trans fluid mixes really bad with the new. You need to drain and refill it a couple more times. Not sure about a power flush though

wbmx1981

It could be the infamous shift solenoid.

gsdthstr

Turns out it was the speed sensors 60 bucks a piece at my local dealer

Did end up flushing the tranny beforehand and it didn't cause any damge. Just an FYI for those weary about tranny flushes