Hey, a problem i'm having is on deceleration at low RPM, the car shakes, and rattles, mainly in the 1st, 2nd, and 3rd gears. I just inspected my u joints, but i'm not sure what to look for, there is no play in the U joints, but i'm able to turn the driveshaft and tranny slightly. Maybe a tranny or a differential problem? How should i go about Properly inspecting my U-Joints? Also I've noticed that the car jumps when going from acceleration to decelleration, or vise versa. I think the car could be much smoother, or are all 7s a bit jittery when decellerating at Low RPMs? Thanks for your time guys, Matt

 

Ok, pull off the driveline.. look at the u-joints on it. Grab the main part, twist the end... if there is any play in it, it's bad. From the sound of your problem, that's what it is... definitely check the fluid level in your rear end, though, too!! oh, and your tranny!! The vibrations is the same prob I had with mine, and it was the U-joints.

 

Thanks alot, I guess the car drove much better after you had it fixed? I have an 83, and aparently the U-joints are replaceable, is this true? How much did it end up costing you?

 

It worked perfectly after I replaced the driveshaft. To my knowledge, the u-joints are NOT replaceable on the 81-83. 84, 85???

It cost me 9 bucks at a junk yard for the driveshaft. there are 4 bolts that hold it on the rear end, but the big pain is getting the shield off!! You may have trouble getting off the driveline from the tranny... just yank. It should slide off.

Also, if possible, park your car with the nose facing downhill to minimize oil leakage from the tranny.

Oh, and DON'T GET THE TRANNY OIL ON YOUR HANDS!!! It will smell like pure nastyness for almost a week.

 

Where can you get replacement u-joints if they are available.

 

The first sign of trouble with the U Joints on my 83 RX7 is they made a clinking sound like a metal part hitting another. Then after awhile, they began to squeek but only when backing up.

 

You do know that this thread is over 5 years old/

 

 

W/ one of my 81s I had a shop replace joints twice but still had vibration. Balanced drive shaft w/ no improvement. I ended up puting in a used shaft combo myself in my driveway that smoothed it out. I think I read somewhere you can't just do the joints on 1 gens.

 

although they sell the u-joints @ partshouse, the RX-7 u-joints are not replaceable. most of my local machine shops wont take the job of grinding the caps off for a few bucks. it means mucho trabajo and no dinero

 

According to http://www.drivewire.com/products/ma...u-joints/8570:

W0133-1635691 Fits these 1983 Mazda RX-7 Trims:

1983 RX-7 2 Cyl 1.1L

So, I guess the U-Joints on an 83 RX7 can be replaced.

 

I had the u-joints replaced on my '83. I just took it to a driveline shop and they did it for about $40 but this was about 8 years ago. They even put in spicer joints.

 

Gleaned this somewhere on the forum.

By jgrewe

A die grinder, big hammer and a punch. To get the old ones out I use a torch to make the 'X" of the old joint disappear then knock the old caps in toward the center. The die grinder is used to smooth out the peened teeth that used to hold the caps in. Once those are smoothed away you can press the new caps in from the outside and use the new internal clips on the new caps.

 

i have replaced u joints on both an 82 and an 83 with no problems. its a bit of a pain in the *** sometimes, but not too bad. 84-85 i believe you have to buy a new driveline, or really work with them to do a replacement.