Hi TM, Super mechanic here. I just wanted to verify the thumping that you are hearing.
Is it when you come to a stop or when you take off?
Or is it a constant rhythmic thump? Thanks
It is possible that one of the U-joints are having trouble pivoting. It is something that you can't see, you have to take it out and check it for smooth movement.
Does it change when you are using the brakes?
Does it seem to increase with speed?
I hear ya'. I can' timagine having to pay what these shops want to even look at a car.
Well, we can't rude out the U-joint(s) yet but what I would like you to do is, when it happens try to touch the brake slightly and see if it either gets louder or goes away.
I want to eliminate a rear brake rotor/drum that may be doing it.
You don't feel it in the steering wheel do you?
It is possible for a U-joint to stop making a noise depending on the temperature and moisture in the air. It would not be very likely though. I would have them checked either way as well as the transmission mount. Just to be sure.