There is a rattle sound coming from the transmission on my 1988 SSE. It'* not very noticeable when just driving around but you can hear it quite clearly with the windows down and when stood outside the car. With the hood raised it is clearly coming from the transmission.

I'm told that this is the bearings in the transmission rattling and that the transmission will need rebuilding or replacing in the near future.

The transmission, dispite being noisy, seems to work well - although it sometimes seems reluctant to shift into overdrive and can be slow to respond to thottle inputs. The transmission also does leak slightly.

Is it definitely the bearings in the transmission? If I leave it, is it likely to deteriorate quickly or will it run fine for a long while as it is?

Thanks.

I thought the same thing on my 89. After I met wilwren (Bill) he told me about the cat rattling. The test: raise car and take a rubber mallet and smack the catalytic converter. If it rattles it is bad.

It seems the sound echoes up the pipe. Replaced my cat and rattle is gone.

I will try that, but I've already kind of ruled out the cat in my mind as in my experience cats when they're gone sound more metallic in their rattle - like a drain pipe rolling down the road. This doesn't really sound like that, it sounds more like when the tappets in an engine get noisey (sort of a slapping kind of rattle) and if you stick your head under the hood with your ear as close as you can to the trans it definitely sounds like it'* coming from there. :? It also sounds louder with the hood up.

Mine sounded the same way. Our oem cats have 3 cores in them. Mine had the middle one loose. Even after it was removed from the car it still looked good inside, but rattled. I had the guy cut it open and the center core was broken in three pieces. If you do get a new cat make sure you go to justmagnaflow and get one there. Mine cost $64 and the shop only charged $40 to cut it out and weld the new one in.

Have you checked the transmission mounts?

Been a few days, have you done anymore with the rattle? What did you find?

Does your car have a catalytic converter? My first cat failure had me absolutely convinced it was a trans rattle.

My second one fooled me again. I'm not kidding, either. If you have a cat, get under there and kick it around a bit.