Differential Flange question

[Kenneth T.]

I have two Corvette pumpkins, one early '68 (date 8/67) and one June 71.

The flanges are different sizes for the U Joint. One will accept a joint that is the same on the drive shaft side or diff side. One has a narrower width on the diff side, so the cross on the u joint is not equal

Anyone know if this odd/ unequal sized flange is original?

Thanks,

Ken

[Kenny C.]

Re: Differential Flange question

It is a Corvette arrangement. I had a 78 rear end with that configuration that I know was original. My 69 however is equal on all sides so there was a change between the years I just don't know when that change occurred. In any case I don't believe that the unequal configuration would be correct for your 68 but it may be okay in 71?

[Joe L.]

Re: Differential Flange question

I have two Corvette pumpkins, one early '68 (date 8/67) and one June 71.

The flanges are different sizes for the U Joint. One will accept a joint that is the same on the drive shaft side or diff side. One has a narrower width on the diff side, so the cross on the u joint is not equal

Anyone know if this odd/ unequal sized flange is original?

Thanks,

Ken

Ken------


I don't completely understand what you're describing here. However, I'll answer this way:

With respect to u-joint configuration, there were 2 different size pinion flanges used for 63-79 Corvettes. 1963-67 and 68-70 with manual transmission used a flange designed for 1310 series (old 1280 series) u-joints. For all of these applications, the transmission yoke, the pinion flange, and the driveshaft on BOTH ends were designed for the 1310 series u-joints.

1968-70 with automatic transmission and all 1971-79 used a pinion flange designed for a 1330 series u-joint. This u-joint has a larger OD than the 1310 series but the end caps are the same size.

[Kenneth T.]

Re: Differential Flange question

Thanks Joe,

From what I can tell now, it looks to be a Mid-Year small block flange that has U bolts, not caps. It drove me crazy for awhile....

I am back in business switched out flanges and moved on. I am bolted up and looking for "wheels on the ground" soon. Your help can have no price.

Ken

[Joe L.]

Re: Differential Flange question

Thanks Joe,

From what I can tell now, it looks to be a Mid-Year small block flange that has U bolts, not caps. It drove me crazy for awhile....

I am back in business switched out flanges and moved on. I am bolted up and looking for "wheels on the ground" soon. Your help can have no price.

Ken

Ken------


The flanges used for all mid years as well as 68-70 with manual transmission all used u-bolts for u-joint retention. The flange used for 68-70 with auto trans and all 71-79 used steel straps with hex bolts for u-joint retention.

By the way, there were 2 different flanges used during the 63-70 period. While both were designed for the same u-joint, the 63-64 flange was 10 spline while the 65-67 and 68-70 with manual trans was 26 spline.

[Kenneth B.]

Re: Differential Flange question

Ken------


The flanges used for all mid years as well as 68-70 with manual transmission all used u-bolts for u-joint retention. The flange used for 68-70 with auto trans and all 71-79 used steel straps with hex bolts for u-joint retention.

By the way, there were 2 different flanges used during the 63-70 period. While both were designed for the same u-joint, the 63-64 flange was 10 spline while the 65-67 and 68-70 with manual trans was 26 spline.

Did you mean all midyear small block use u-bolts. All four of my 67 427'S have Cast straps & hex threaded hex bolts? I am sure these are correct for Big Blocks.
KEN

[Joe L.]

Re: Differential Flange question

Did you mean all midyear small block use u-bolts. All four of my 67 427'S have Cast straps & hex threaded hex bolts? I am sure these are correct for Big Blocks.
KEN

Ken------


I think we may be mixing "apples and oranges" here. The original question involved the PINION FLANGE. My responses related to the pinion flange and associated parts (u-joints, driveshaft, and transmission yoke). ALL 1963-67 Corvettes as well as 68-69 with manual transmission used driveshaft u-joints that were retained by u-bolts. This includes small block and big blocks. If you actually mean that your driveshaft u-joints are retained by straps with hex bolts, then that's not a correct configuration for any 1967.

I think what you're referring to is the differential SIDE YOKES (stub axles). All 1963-67 small blocks used side yokes which retained the u-joints by u-bolt. 1965-67 big blocks used side yokes that retained the u-joints by cast iron cap with hex bolts.

[Kenneth B.]

Re: Differential Flange question

Ken------


I think we may be mixing "apples and oranges" here. The original question involved the PINION FLANGE. My responses related to the pinion flange and associated parts (u-joints, driveshaft, and transmission yoke). ALL 1963-67 Corvettes as well as 68-69 with manual transmission used driveshaft u-joints that were retained by u-bolts. This includes small block and big blocks. If you actually mean that your driveshaft u-joints are retained by straps with hex bolts, then that's not a correct configuration for any 1967.

I think what you're referring to is the differential SIDE YOKES (stub axles). All 1963-67 small blocks used side yokes which retained the u-joints by u-bolt. 1965-67 big blocks used side yokes that retained the u-joints by cast iron cap with hex bolts.

Ok you are correct. I misunderstood the question. I didn't think there was a question about the pinion flange. Most questions with the diff.carrier are about the side 1/2 shaft yokes because there are u-bolts for small blocks & straps & hex screws for big blocks. I should know that the word assume always gets me in trouble.