2001 ls 430. 166k, When approaching stops and at almost a near stop I get a final clunk or thud before the car rests. Possibly the final downshift when vehicle is stopping. The faster I come to a stop, the more intense the thud/clunk. Any ideas?

 

First, try coming to a stop in neutral. If the noise is gone, possibly a tranny issue. If the noise remains, I'd start looking at your suspension and checking everything for any play...

 

Also look at the bolts that hold the calipers. I had one get loose one time and drop the end of the caliper. Terrible noises and just knew I was going to die. But replacing the lost bolt solved the problem.

 

I just drove it and the thud was absent while stopping in neutral. Thanks.
So. Could it be shift solenoid? Could "not so clean" fluid be an issue? Drain and fill? Flush?

 

I used up all of my tranny troubleshooting with the neutral suggestion. Obviously, if the fluid has never been done then you should do that but I don't think that will fix whatever your issue is. A more robust OBD2 scanner should be used to check for any codes also...

 

Thanks. With a bad mount would the clunk come at the same time everytime or at different times? Because the clunk is consistent right at the last downshift, decreasing to about under 12mph

 

Its a single thud. It just sounds to me that it is downshifting hard to its final gear before stopping. How do I check for poor tranny mounts. If motor mounts are the same thing then I tested them by revving the engine real high several times while in park and watched for any tilting of the engine. Are tranny mounts are different?

 

Good stuff. Thanks. Will there be any play that I could see/feel by moving it or shaking a bit? Or am i just looking at the cushions.?

 

If bad mounts... then would I only feel the thud at one interval or should I hear it in other situations of shifting or downshifting?

 

Tranny fluid was low. I topped it off with 1/3 qt, The sound, "Thud" is no longer present when I am coming to a stop. So just topping off the fluid worked

 

Thanks for closing the loop on your issue and reporting back to us with the solution...