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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

how can u tell u joints are bad???

  • Thread starter Thread starter J-Scratch
  • Start date Start date Jun 2, 2004

J-Scratch

Member
Apr 23, 2004
74
0
6
Jun 2, 2004
#1
  • Jun 2, 2004
  • #1
other then the druve shaft falling off, and u killing yourself?
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Jun 2, 2004
#2
  • Jun 2, 2004
  • #2
bad u-joints make noises. Clunking when you put the car in gear, rattling at higher speeds.

They make a LOT of noise before they fail. It's not a subtle thing.

I would think you could block the car in place, put it in park, jack up the rear, and try rotating the driveshaft. A bad u-joint would be sloppy.

I've never tried anything like that. I've just driven the car until the noise is too annoying, then taken it to a shop to check it/fix it.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Jun 3, 2004
#3
  • Jun 3, 2004
  • #3
Pull the drive shaft. Then work the U joints, if one's bad it'll be stiff. Also can pull the cups and see if any are dry. You can also push-pull on the shaft while it's on the car sometimes and see if any are sloppy.
 

65 A Code

Member
Apr 6, 2004
136
1
17
Jun 3, 2004
#4
  • Jun 3, 2004
  • #4
are U joints something you can replace yourself? or is it better to have them replaced by a shop?
 
S

slapper

Founding Member
Mar 6, 2002
447
0
0
Jun 3, 2004
#5
  • Jun 3, 2004
  • #5
It's easy.
Use a bench vise and some sockets, and a pair of internal snap ring plyers.
If you are removing / installing U-joints with grease fittings, just be aware of the position of the fitting so that it's accessable when the new one is installed.
 
H

Homercidal

New Member
Jan 15, 2004
45
0
0
Michigan
Jun 3, 2004
#6
  • Jun 3, 2004
  • #6
This is a basic repair and most how-to books will have the instructions in them.

I think it's a matter of marking the position of the joints so that you can put the driveshaft back in the same splines.

Unbolt the joints and remove them. Drive out the old bearings using socket and vise. Install the new bearings with vise and sockets. Replace joints lining up marks and bolt down.

It's been a few years since I've done that. I think it was my '83 Cougar.

Hopefully I'm not steering you wrong here, but I know it is a SIMPLE repair, so have courage!
 

65 A Code

Member
Apr 6, 2004
136
1
17
Jun 3, 2004
#7
  • Jun 3, 2004
  • #7
I have not checked mine to see, but I figure when I have the drive shaft out might as well replace them. Did not appear to be too hard to do. What about cost?
 

txwoody

Member
Jun 2, 2004
99
0
6
4 hours to anywhere, TX
Jun 3, 2004
#8
  • Jun 3, 2004
  • #8
It's a easy check. Just jack up the rear. Make sure the wheels are off the ground. Put some jack stands under it. Take it out of gear so that the driveline spins free. Just rotate the driveline and try to move the U-joints up and down if there is any play then they need to be replaced.
 

J-Scratch

Member
Apr 23, 2004
74
0
6
Jun 3, 2004
#9
  • Jun 3, 2004
  • #9
I figured out the problem it was not the U-Joints LOL
My car was vibirating, and gradually was getting worse. First I figured the muffler, then it got worse I figured it was the U-joints. I jacked uup the car and those two scenarios were x-d out my muffler is on a year old the drive shaft was solid. It was a broken bolt on the engine mounts.. Drama!!!!!!!!!!!!
should have it fixed by thos weekend. What a b!t@h trying to figure that out. Then there it was right under the hood. Oh well
alway's something.
 
H

Homercidal

New Member
Jan 15, 2004
45
0
0
Michigan
Jun 4, 2004
#10
  • Jun 4, 2004
  • #10
65 A Code said:
I have not checked mine to see, but I figure when I have the drive shaft out might as well replace them. Did not appear to be too hard to do. What about cost?
Click to expand...


The are very inexpensive. I can't quote actual dollars right now, but they are approx. what wheel bearings cost I believe. I'd guess less than $20 a set.

Someone set me straight if I'm wrong.
 

Gummi Bear

New Member
Sep 29, 2003
86
0
0
Arlington, Texas
Jun 4, 2004
#11
  • Jun 4, 2004
  • #11
OK -

U-joint 101 is in session.

I've been through scores of joints over the years, extreme angles, big tires, and lots of torque = lots of broken joints. They are easy to change, if you don't have a vice or a press, the old whack-it-with-a-socket trick does well. Get full circle clips (not the half clips, they'll spit out, and you have a broken joint, and a broken yoke, not to mention that your shaft will bounce around and beat your car, and third member. Nobody wants that.

Go to a driveline shop and get some Spicer Life Series joints. All others are inferior (the voice of experience speaking here) Figure about $15 per joint (you'll need 2) they are worth the money. Don't be the guy that replaces only one, replace them both, and be done with it.


For you tech hungry folks out there, here is the very best article I've ever seen on u-joints, and what makes them work. Billavista U-Joint Tech Article
 
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