driveshaft question
 

there is a very loud thumping noise coming from the driveshaft, u-joint or something near that, when this happens, it actually hits the bottom of the car, do these cars have a split driveshaft, like its in 2 peices and something connects it in the middle? i have asked 3 people, 2 think its a u-joint and a mechanic that lives near me thinks its the split driveshaft jetting up when there is torque applied. it happens when the car bucks, like many of yours do probably, if not enough gas is applied in 1st, 2nd, or 3rd. it also happens, if you hit the gas to hard when shifting, so unless i shift as perfectly as humanly possible, this noise happens. it sounds like someone smashed a tree with a metal bat, thats the kind of noise it makes, very loud. it is also effecting the performence and there is increased vibrations, any ideas????

As for the shaft. It's a single piece shaft.

As for the noise, could it have something to do with a throw out bearing or something of that nature?

Fikshun

it doesn't make the noise in reverse, thats why we thought it was a 2 piece shaft, so it would have gone down instead of up, so when it goes forward it would hit the car, but anyone else have an idea? and what is a throw out bearing by the way

It's the front mount on your differential, not your driveshaft. Probably thumps everytime you shift gears. Replace same.

wait...can you clarify that a bit, what do i need to replace? and where is that?, yes it does everytime i shift, unless i do it conciouslly perfect everytime, which i can but its a pain, and how hard would that be to do...thanks...gerry

I'll try to find a picture. There is one in the online manual for the 88cars. http://www.iluvmyrx7.com then go to manuals, and then the chapter on the rear end.

The differential is held on the car by three rubber/metal mounts. The rear two are very dependable. The front one is very dependable until the car gets 10-15 yrs on it. Then the rubber seperates and lets the nose of the differential rotate in an upwards motion, striking the floor of the car during acceleration. It cost a bit. See Mazdatrix.com and look. Here... http://www.mazdatrix.com/g8.htm the second picture.

Some people say its easy to change....some say not. I consider it a pain. Some people are more talented than others or they have a high threshold of pain. I'll see if I can find a picture on this site. I know I've posted one in the past.

I couldn't find the picture on this site. Look at this thread... https://www.rx7club.com/forum/showth...threadid=39026

Let's see if this image from the past works...
https://www.rx7club.com/forum/attach...&postid=880442

Yeah! That worked. The mount is surrounded with the red dots. That image along with the picture from Mazdatrix.com should give you a idea of whats happening. Also look at the ARCHIEVES for the 2nd generation. There's a thread about the mount.

Bad U-joints go "tink" or "clink" when you start out.
Bad front diff mount goes "clunk" or "thunk".

With a clink tink here and a clunk thunk there,
Old McDonald had a seven E-I-E-I-O.