'72 U-joints...Flat capped or recessed?

[Bill B.]

Late march build, which U-joints should be used for restoration. Flat capped, or recessed caps?

Thanks,
Bill

[Edward J.]

Re: '72 U-joints...Flat capped or recessed?

Bill, I would bet that GM had a few venders that made the u-joints, if it helps I have a few original axle joints from a 64, they have small recess in the caps, I can take a few pictures if you like. The half shafts and driveshaft were the same for quite a few years.

[Bill B.]

Re: '72 U-joints...Flat capped or recessed?

Thanks for the reply Edward, and no need to take pics, have both versions. Hearing that some years judges like to see flat, and other years recessed. Just not sure about a late '72. Going to use recessed unless I hear a definite no.

[Joe L.]

Re: '72 U-joints...Flat capped or recessed?

Bill, I would bet that GM had a few venders that made the u-joints, if it helps I have a few original axle joints from a 64, they have small recess in the caps, I can take a few pictures if you like. The half shafts and driveshaft were the small for quite a few years.

Edward-------

I totally agree. GM was using these u-joints by the millions across all car and truck lines. There was AT LEAST 2 manufacturers that I know of----Spicer and GM's own internal manufacturing. There may well have been others, too. The only way to know which u-joints a particular car had would be to have the original u-joints from that car.

[Ed D.]

Re: '72 U-joints...Flat capped or recessed?

My 72 was called out for recessed u joints in Mobile. 1point
Ed

[Bill B.]

Re: '72 U-joints...Flat capped or recessed?

Ed, thanks for the reply, what is your vin derivative?

[Robert N.]

Re: '72 U-joints...Flat capped or recessed?

I have not seen them all but, every original corvette from 65-72 that I have seen has flat caps.

[Bill W.]

Re: '72 U-joints...Flat capped or recessed?

Does anyone have a source for flat capped u-joints?

[Mark M.]

Re: '72 U-joints...Flat capped or recessed?

I recently installed all 6 joints in a 65 I'm restoring with all flat caps from Paragon. Non grease fitting, I would call to confirm before ordering. Bair's may also have them as they are excellent suppliers of chassis parts and great to deal with. Call first before ordering for part specifics.

[Mark M.]

Re: '72 U-joints...Flat capped or recessed?

Also the paragon joints had the grease fitting cast in bump which wasn't drilled. All replacements I've seen have this. I believe originals don't have that bump, I'd have to dig out some original shafts to check. Many years ago I seem to remember a number of later c3s with spicer on half shaft caps. It was also the joint the dealers would sell you in the 70s and 80s at double the price of other suppliers. The Spicer is a top quality joint.

[Joe L.]

Re: '72 U-joints...Flat capped or recessed?

Here are some photos of GM #3830580 and GM #3849500 u-joints. These u-joints were used in the 1963-68 period on Corvettes. I believe that these particular joints were of internal GM manufacture, However, it's very possible that other examples of these same part numbers were manufactured by Spicer or others.

DSCN4019.jpgDSCN4020.jpgDSCN4021.jpgDSCN4022.jpgDSCN4023.jpgDSCN4024.jpg

[Mark M.]

Re: '72 U-joints...Flat capped or recessed?

Joe, do you have a 3832031 or 3872922 ; both are listed in 1942-1965 chevrolet parts catalog as 1963-65 corvette diff. carrier U-joint. Strangely the later # is listed as 65 corvette w/P/Trac ? Also do you have a 3889696, from 1974 corvette parts catalog ? All are half shaft joints.

[Ed D.]

Re: '72 U-joints...Flat capped or recessed?

21344, May 15 72

[Bill B.]

Re: '72 U-joints...Flat capped or recessed?

Joe, thanks for the pics. I'm routinely taken back by your extensive knowledge on GM parts.

Originally brought this up as I thought it was either one or the other. At least in the case of spring of '72, it looks as there are some with recessed. Here are a couple of recently acquired pics of two original late 72s. One built in April, the other in July.

[Ed D.]

Re: '72 U-joints...Flat capped or recessed?

I know my u joints were replaced about 25 years ago, and dont remember what was there originally. They were replaced with spicer, no grease fitting joints.
#21344, May 15, 72