i read in my Hanes manual that instead of replacing the U-joint itself, it's better to replace the entire drive shaft? Is this absolutely necessary?

 

I believ on 83+ you have to, you got no choice...

I had a local fabricator do mine on my 80. He charged like $20 bucks labor just took him the parts and the driveshaft walked out 15 minutes later put it on and was happy. No fuss no BS. They make driveshaft and rebuild CV joints. And have the proper measuring equip. and balance equipment..

 

Its probably easier to replace any shaft with a worn u-joint then try to repair it. Its something to do with keeping the shaft balanced. At 3000rpms, an unbalanced shaft can wobble and wear out some bearings or something.

 

nice, now I just have to find the money.....

 

pick one up from a junkyard for about $20-30.

 

You could pick one up at a junkyard, but what if that's on it's way out? You're probably better off buying an aftermarket one as the Mazda one is pretty expensive.

 

I went the new driveshaft route on my 84 and bought the Mazdatrix one w/ replaceable U-joints, $257.04 delivered. (Ordered Monday got it Friday.)

http://mazdatrix.com/getprice.asp?partnum=2691-701

A fair chunk of change, but worth it IMO since it made a big difference in my car. The vibration and clunking I had is now gone, and the shifts seem much smoother.

The only wrinkle is that I had to pound out a portion of the heat sheild between the cat and driveshaft since the front yoke on the new shaft is a bit larger in diameter then the stock one and was rubbing.

 

What year car you got, Ill sell ya mine from my 85.. All I need is the rear of your old one if its an 85...Mine worked perfect, no clanks, no pop no noises...

 

Mine's an 85 also. How much would you sell it to me for?

 

Later year shafts CAN be rebuilt. I called a driveshaft shop today to have my '85 fixed. $44 for parts, $35 for labor, 3-4 days to perform the work. Balancing is included. Not a bad deal. You just need to find someone with a little experience.

After rebuild, it's headed for shotblast (a work perk) and paint.

 

Buckaroos....

I tried two different shops here is Central Ohio. Sent shafts in for u-joint replacement and balancing. Both came back better than before, but still had vibrations at certain speeds. Sent one back to the shop for further balancing and it came back still with a vibration at 45 mph! Dealer wants $400 for a new one. I gave up trying to find a fix....Money out the exhaust pipe.
Ended up going buying one from Mazdatrix, and that's my advice....Mazdatrix. One's in my local yard have way too many miles on 'em, and have been sittin' outside too long...

Denny,
From the 'ol corncrib...

 

ok, I'll try Mazdatrix, thanks guys!