Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (
-   Transmission - Rearend (
-   -   Gm ujoints (

spinn 11-07-2012 09:21 PM

Gm ujoints
I can easily identify mopar u joints, but these gms are little different. For a 1985 c10. I believe they are R3 joints on a one piece 55.5" long shaft from a 1985 C10. Cannot figure it , the out caliper states 1.79" dia cap.

Are R3 joints a 85 c10 replacement?

Can you replace the straps for u bolts at the differential pinion yoke? DR\rill the yoke threads out, if one is stripped. Then use u bolts.

SSedan64 11-07-2012 10:27 PM

1 Attachment(s)
1350 = 1.188"
3R = 1.125"

Do they have Lock Rings?
3R uses injected Nylon if Stock/OEM, Replacements use Internal Rings.

spinn 11-07-2012 11:44 PM

1 Attachment(s)
They are 1350 my caliper has had a lot of wearover the years. Btween 1.18 and 1.19 so that makes sense. I have a nice aluminum driveshaft from a envoy that i was going to alter.

THey might be called r1 not r3. I know the stardards are 1 3/16th cap and 1 1/4 cap.

Is there a kit to convert to u bolts instead of straps?

SSedan64 11-08-2012 12:03 AM

8.5" Rear?
You gonna change the Pinion Yoke or use a Conversion U-Joint?
U-Joint Fasteners -

spinn 11-08-2012 12:17 AM

Yes a 8.5 rear. I forget the .1 so they are 1.179- ish. That makes them 1350 u joints.

The straps are okay , but im looking for a u bolt retainer. Can I drill the yoke?

SSedan64 11-08-2012 12:34 AM

The 8.5" Pinion Yoke will most likely be a 3R size which is small so you would need to change the Pinion Yoke to use a 1350 U-Joint or use a 3R/1350 Conversion U-Joint & drill the 3R Pinion Yoke for U-Bolts or use Al. Caps.
If you want strength you should change the Pinion Yoke and Slip Yoke to 1350 size to match the DS.

SSedan64 11-08-2012 12:39 AM

I don't know if they even make a 3R to 1350 Conversion U-Joint.
Look thru these:

All times are GMT -6. The time now is 12:51 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.