tranny problem or engine/tranny mount?

[jbjslambert]

1997 lesabre tranny sort of just "falls" into gear in 3rd and overdrive,not smooth. maybe motor mount? if so which one tends to go bad first.

also tranny or actually i think the torque converter seems to kick out when i let off the throttle and when i get back in it at cruising speed it kicks back in and rpms drop back again, this normal operation?

[dudealex1]

All the Buicks that I've driven have always had what felt like a "weak" overdrive... the rpm's just rose 100 or two and then it would fall into drive... Nothing like the crispness of a Honda or Toyota, it's meant to be smooth.

Still, you shouldn't feel a "shake" or "shudder" when it shifts... make sure to check your tranny fluid level with the car running also. The condition of the fluid can tell a lot.

As for accellerating, at low throttle it shouldn't downshift; at medium throttle it'll kick back at about 3000-4000rpm's and then downshift quickly (at least 1000 rpm before redline); at full throttle it should kick back in the lowest gear possible and then shift about 100-200 rpm's before redline to the next lowest gear possible.

Check the fluid level and condition, let us know if there is a vibration/shake or sound when it shifts. And does it slip?

[Hapynzap]

My 99 was starting to shift like that into 3rd. I put some zmax in it and it shifts nice now. You might try some Lucas too. Have you changed the fluid and filter ever?

[jbjslambert]

ya i checked fluid before hand. and ya its pretty dirty. trany never slips even at full throttle. car shifts fine it just it seem to shift harder in 3rd and into overdrive. but not all the time seems to be related to where the throttle is at time of shift. when i first got the car it had tps code in it, we cleared it and has never came back. gonna change the filter and put the 5 or 6 quarts back in but dont wanna do a complete flush on it due to 130,000 miles. thought an idea of motor mount due to it dont feel like that when under a good load just when "cruising" with minimal throttle input. let me know what ya think, thanks joe

[Hapynzap]

Mine would shift hard (clunk) into 3rd under acceleration onto a freeway. zmax has smoothed it out for my '99.

This isn't something I take lightly as I am on my 4th transmission in my '85 Century