The13Bats

Okay, my car is still at the shop so I can't pop out and look,
I get a message from the tech today that while the body went on the chassis nice the rear u joint is too wide for the yoke on the diff.

The original car was a 69 small block car which the tech matched up the u joints on that 69 drive shaft when I bought new ones BUT the donor chassis was from an early 68 I have no idea if bb or sb and because the chassis was over hauled and rebuilt with vette brakes transverse kit and who knows what mismatched parts it has & I have no clue what is what.

So to try to be simple what would make the rear u joint too wide for the diff yoke?

Many thanks!
The bat vette is close to coming home....

wombvette

Some later models had different u-joints. My guess the rear is out of some later model. The 68-69 should be the same bb or sb.

The13Bats

My 68 donor is something of a frankenvette so it's anyones guess

What I found on the Duntov site,

"65-79 Differential Pinion Flanges

These are reconditioned flanges, guaranteed to be perfect. The 65-70 unit is 3 7/8 inch across, while the 68-79 is the larger size, at just over 4 1/4 inches across. "

So there is odd overlap in years but mine could be the early/smaller yoke,
Now to figure out the easiest fix...

'75

The easiest fix is a conversion u-joint, it has the 1310 size and the 1330 size, spicer 5-134X for the greasable one. 253 for the non grease style

Gale Banks 80'

Keep in mind that Switching the Yoke could change the set up of the pattern of the Ring and Pinion. Although it has been done many times before. Also keep in mind that the U-Joint Straps that hold this u-Joint is a Corvette specific part. The Split between the Flange and Strap is not centered, the Straps are shorter than normal. This may or may not be true on Your specific car. Don't expect your local Auto parts store to have them. Napa doesn't. Corvette Central does.

The13Bats

Seems the easy way to solve this issue is the special u joint?

According to the net my local stores like orielys autozone etc do carry spicer 5-134X u joint or a crossover which it would appear will mate my wide ds yoke to my narrow diff yoke...this will work right?

63mako

The 1330 rear flange is 1968-1969 Auto and 1970-1979 all. the 1310 flange was used 1963-1967 and 1968-1969 4 speed. You can't change the flange out because the pinion shaft is different diameter and spline. The conversion Ujoint is the answer. I use the non greasable ones. Way stronger and you can't access it to grease it once installed in a vet.
It will work fine. Had one on my 63 when I got it.
Here you go. This is the non greasable one. Picture is wrong.
http://www.summitracing.com/parts/MOG-253/
This is the greasable version
http://www.summitracing.com/parts/mog-353/overview/

redvetracr

incorrect, you can interchange 65-69 yokes with 70-79 yokes

63mako

That is odd, I tried and I believe my pinion shaft was bigger around on the newer unit. It was a long time ago. I have a 1330 yoke. If 13 Bats wants it it's his free, I will cover shipping.

The13Bats

Mako, many thanks, I would take you up on that but lets be sure I can use it before going to the trouble,
My diff yoke I now have is the narrow I need the wide is that what you have you could set me up with?
The diff diagram I pulled up appears that the yoke is a bolt in item easy to swap?
Gale Banks posted something about you cant just swap out yokes due to it could change the set up of the pattern of the Ring and Pinion, which I am no way savvy on, but redvetracr says you can swap them, you said didn't work for you...I'm all confused.

Tampa Jerry

I had this problem with my Chevelle. I got the joint at Fleet Pride in Tampa. They have them in stock and changed it out for me in a few minutes. I see you are in Orlando. Worst case, take a drive over here with you parts and they will fix you right up. Jerry

The13Bats

Pretty much all the local parts store carry the u joint that '75 posted the part number for as cross ref,
I am just trying to be sure I do it right this time...

doorgunner

You gotta love it.........



"it'll work"/"no it won't"

63mako

There is a crush sleeve, generally one time use that sets your preload. If your careful you can measure the drag while turning the pinion nut in inch lbs. Set it down, remove nut and pinion flange, replace seal, coat pinion flange splines with permatex #2 and install new pinion flange, put locktite on new nut, tighten nut until you have the same drag in inch lbs when you turn it as you had originally or 1 inch LB more to maintain crush on sleeve and maintain correct pattern. 1330/1310 u joint is WAYYYY easier. That said if you decide to swap the pinion flange out let me know. Offer stands.

Edit: As I said I think the pinion splines and shaft is different but I could be wrong. It looks like 63-79 is the same here. http://www.ecklerscorvette.com/1968+...erentials.html