Does it feel like you are running over rumble strips placed on the road? Does it happen when the transmission is downshifting when going up a slight incline?
If so, this is a very common problem on the first generation cars.
My 93 LS did this until I had the transmission fluid drained and refilled. This was about three years ago, and the problem has never returned.
Make sure you use the right fluid. My 93 calls for Type II fluid, which is no longer being made. The Toyota Type IV is its replacement. I am not sure which fluid a 91 LS would need.
That sounds like the same problem I have. It feels like I'm driving on dirt road. I'm not sure it happens when shifting down. It happens when I'm driving around 40-50mph and it lasts few seconds. So does that caused by bad tramsmission fluid? I just spent $800 to replace the water pump and timing belt. Hope it won't cost that much this time.. Thanks for the tip!
Vibration From 40-60 Mph
in 90 - 00 Lexus LS400
Posted
That sounds like the same problem I have. It feels like I'm driving on dirt road. I'm not sure it happens when shifting down. It happens when I'm driving around 40-50mph and it lasts few seconds. So does that caused by bad tramsmission fluid? I just spent $800 to replace the water pump and timing belt. Hope it won't cost that much this time.. Thanks for the tip!