U Joint question for a 1957 Cadillac Series 62

[Cadillac Jack 82]

I need to replace my u joints in my 1957 as they clack when I shift from drive to reverse and back again.  I was looking over the shop manual and it appears I'll need 3 of these?  Can anyone confirm this?  Also should I replace the drive shaft bearing while I'm at it?  Does anyone also have a specific vendor they would recommend for these parts?  I want quality parts that will last.

[Walter Youshock]

2 piece shaft so there's 3 joints.  You may want to take it to a drive shaft place to have the work done and have it balanced.

[Cadillac Jack 82]

I could but I don't have the extra couple hundred to do that at the moment.  The only reason I suspect the u joints is the clank noise I hear when going from drive to reverse and then there is a very mild vibration from 40-50 MPH that eventually goes away as I go faster. 

[Walter Youshock]

Mine started chirping.  Check to make sure one of the center support bolts didn't break.

[Cadillac Jack 82]

Its not a chirp...more of a clu-clunk noise which makes me think that the u joint is worn

[Quentin Hall]

U joints are a relatively easy job so long as you can get the car onto a 4 post hoist. Trying to do It on jack stands is a  pain. Most bearing shops carry them even here in Oz. I'd probably just get  it up and check manually for wear. Your clunk sound might be a bit of diff wear as well. My motto is if it ain't broke . . . . You will know as soon as you give them a wriggle .

[Cadillac Jack 82]

Luckily I have access to my uncles shop.  He's a mechanic and he has his own section of the shop all to himself.  I typically bring it by when he's working on a weekend and we do what we need to do after he wraps up his jobs for the day.  Since I need to remove the yoke in order to replace the leaking tailshaft seal I might as well address the entire drive shaft assembly too.

[Cadillac Jack 82]

Quick question about balancing.  I just called a local shop in the DC area that said they would balance my drive shaft for 125.  Does that seem like a reasonable price?

[savemy67]

Hello Tim,

Does the shop in DC know that the driveshaft is a two-piece driveshaft?  If so, the price does not sound outrageous.  If that shop does balance the driveshaft for you, the new u-joints should be installed before you give them the driveshaft, or you can pay them to replace the u-joints.

As Quentin implied, there are several locations in the driveline where excessive wear or backlash could cause the clunking noise you hear:  splined axle shaft ends to differential side gears, side gears to spider gears, differential ring gear to pinion gear, three u-joints, driveshaft center bearing, splined driveshaft yoke to transmission output shaft, internal transmission components.  If all these locations have a small amount of backlash or wear - 0.010" - the total driveline backlash or wear could add up to 0.100", which could result in an audible clunk.

You may want to check the u-joints using the wriggle method.  Grab an end of the driveshaft near a joint, and try to move the driveshaft back and forth.  Rotate the driveshaft 90 degrees and repeat.  Do this two more times so you load each of the four caps on the u-joint.  Do this for the other two joints.  If no perceptible movement is felt, the joints are probably OK.  Proceed to checking the center bearing attaching bolts, and that they are tightened to spec.  If the attaching bolts appear to be OK, remove the driveshaft to check the bearing, but be sure to match-mark the driveshaft at both ends before removal.  If you or your uncle replace the u-joints, match-mark the two pieces of the drive shaft.  Good luck.

Respectfully submitted,
Christopher Winter

[Cadillac Jack 82]

Thanks savemy67

[savemy67]

Hello Tim,

Another message on the forum prompted me to add that you should check to see if there are any missing shims under your driveshaft center bearing.  Mis-alignment of driveline angles can cause vibration and perhaps aggravate an excessive backlash condition.  If you have the '57 shop manual, see if it mentions driveline angles in the driveline section.

Christopher Winter

[Cadillac Jack 82]

Yup I have a shop manual.  I'll use it when I inspect my drive shaft

[Cadillac Jack 82]

I see that there are bearings out there for the center...who makes the best one?  I'm going to replace this too.

[Walter Youshock]

I don't remember what company I used but it should be sealed.  Replacing just the bearing means separating the bearing housing that was spot welded.  It's a real pain.

[Cadillac Jack 82]

Hmm dunno if I wanna be breaking any spot welds.  If thats the case I'll leave it alone.  I'll definitely replace the rubber bushings for the bolts though.  Rubbertherightway.com sells a kit