The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-27-2011, 11:22 PM   #1
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
U joint problems

Okay,
so I was driving along and my u joint snapped, fortunately I was driving barely 5mph at the time and no real damage was done.

The U joint is messed up and needs replacing, and the part of the rear axle that holds the u joint in place is also messed up.

What is the proper name for this part?
It sticks out of the axle, towards the front of the truck, and you bolt the u joint from the drive-shaft into it. Also, what size is that bolt that holds it to the axle?

Help anyone?


EDIT:
This is from a jeep but it looks similar to the item on the left
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Old 10-27-2011, 11:45 PM   #2
Gyawo
Registered User
 
Join Date: Dec 2010
Location: Alberta
Posts: 165
Re: U joint problems

Not too sure on the size of bolt, try something upwards of an inch. The piece that comes out of the diff is called the yoke. You may need new end caps for it if they are stretched like that. Depending on how chewed up the end of your driveshaft is, I would suggest taking it to a drive line shop and seeing if they don't mind throwing it on a balancing machine to check if it is out of whack.

Had the same thing happen on my K5, was expecting it eventually though. Love how it happens, hear a WHACK WHACK WHACK, and then thump thump thump...
Gyawo is offline   Reply With Quote
Old 10-28-2011, 12:28 AM   #3
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

Quote:
Originally Posted by Gyawo View Post
Not too sure on the size of bolt, try something upwards of an inch. The piece that comes out of the diff is called the yoke. You may need new end caps for it if they are stretched like that. Depending on how chewed up the end of your driveshaft is, I would suggest taking it to a drive line shop and seeing if they don't mind throwing it on a balancing machine to check if it is out of whack.

Had the same thing happen on my K5, was expecting it eventually though. Love how it happens, hear a WHACK WHACK WHACK, and then thump thump thump...
Yeah haha, that's exactly how it happened.
Driving along no problem.....then THUNK THUNK THUNK

Luckily I was able to pull off almost instantly, I'm really glad it didn't happen going 60+ mph.

But I will definitely need to get the yoke and a new u-joint.

I'll take some pictures later and show you what the damage is.

It looks to me like straps on the yoke holding the u-joint were bent and let the u-joint wiggle loose and out.

I know I can pick up a u-joint at O'Reilly, but do they also carry that yoke or will I have to look elsewhere?

Thanks for the quick reply.


Here's a pic:

Notice how that top right bolt is bent out? I'm not sure if it caused the u-joint to come out, or that was just a result of it, but either way it looks like I'll be needing a new one!
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!

Last edited by Kutzy; 10-28-2011 at 12:36 AM.
Kutzy is offline   Reply With Quote
Old 10-28-2011, 12:53 AM   #4
54Caddy
GM Addicted
 
54Caddy's Avatar
 
Join Date: Jan 2009
Location: Visalia, Ca
Posts: 2,294
Re: U joint problems

if its a 12 bolt the socket size is 1 1/8 socket. And get a good quality u joint and straps from precision u joints. good stuff and worth the price.
__________________
..Mac’s Garage..
73 GMC, 54 Caddy, 2010 Silverado, 68 C10 RIP DAd

My 73 GMC Truck Build Pic
2010 Silverado 4/6 on 24s

IG:MacsGarage
54Caddy is offline   Reply With Quote
Old 10-28-2011, 01:12 AM   #5
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

Yep, it's the 12 bolt rear end.
And will do! Thanks for the advice.
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Old 10-28-2011, 02:12 AM   #6
rwhit57
Registered User
 
rwhit57's Avatar
 
Join Date: Jan 2011
Location: Tulsa,Okla
Posts: 590
Re: U joint problems

The failure was not likely the yoke or straps but the u-joint itself. It seized up and had no place to go but apart. That yoke can be repaired if the cup seats aren't damaged. The bolts can be removed and run a tap through the threads. A couple of new u-joints and straps, and like was said take the driveshaft in and make sure it isn't bent.
rwhit57 is offline   Reply With Quote
Old 10-28-2011, 03:50 AM   #7
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

I went and took a look the best I could in the dark and it looks like that differential yoke piece is toast.

So I took measurements for a new one and what universal joint I'll need.

It appears to be 3 5/8" from cap to cap and the diameter of the cap seems to be about 1 1/8", does this seem correct for this model/year?

I think I may have found one on eBay that will work for me.

I'll also be taking the drive-shaft in to check for straightness.
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Old 10-28-2011, 07:08 AM   #8
1981Sturgis
Registered User
 
1981Sturgis's Avatar
 
Join Date: Jun 2010
Location: Vermontville, Mi
Posts: 80
Re: U joint problems

Would this have a crush sleeve, and should it be replaced also? And torqued properly.
1981Sturgis is offline   Reply With Quote
Old 10-28-2011, 11:45 PM   #9
raceman6135
Dino burner
 
raceman6135's Avatar
 
Join Date: Nov 2002
Location: Calgary, Alberta, Canada
Posts: 602
Re: U joint problems

Quote:
Originally Posted by 1981Sturgis View Post
Would this have a crush sleeve, and should it be replaced also? And torqued properly.
Yes, it would have a crush sleeve, unless the owner or a previous owner went through the trouble of setting it up properly with a solid spacer (the vast majority of people stick with the crush sleeve because setting up a solid spacer is quite difficult and time consuming)

The differential must be disassembled in order to replace the crush sleeve, and since there is no indication that it was damaged, it's highly unlikely that it needs to be replaced.

When the OP replaces the pinion yoke, he should carefully mark the relationship between the pinion, pinion yoke and pinion nut. Also record the number of threads exposed on the pinion BEFORE the nut is removed. This will help with reassembly. A repair manual MUST BE CONSULTED before this repair is performed, unless someone has a link to share which will help the OP.

OP: while you have the yoke off for replacement, it would be prudent to replace the pinion seal at the same time.
raceman6135 is offline   Reply With Quote
Old 10-29-2011, 12:00 AM   #10
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

Thanks for the info raceman!

If someone has a step-by-step guide it would be much appreciated!

I still have a few days until the parts get in so I'm reading up as much as I can to find exactly what I will need to do.
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Old 11-01-2011, 03:49 PM   #11
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

Update:
I just got my new yoke in the mail today.
I will be going tomorrow to buy the u-joint, straps, etc.

After looking up the part number on the yoke, it uses a 1330 series u-joint,
does anyone know what series u-joint the drive-shaft uses originally?

Will I be able to simply buy a 1330 series u-joint or will I need a 1310-to-1330 u-joint?

Will be happy to have my truck moving again!
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Old 11-08-2011, 03:07 AM   #12
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

I still have a few items to get, so here's a bump hoping someone has an answer to my question!

kutzy
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Old 11-12-2011, 12:46 AM   #13
Kutzy
Registered User
 
Kutzy's Avatar
 
Join Date: Oct 2011
Location: Las Cruces, New Mexico
Posts: 29
Re: U joint problems

Okay, I finally got it all fixed and buttoned up and it's running great!

It turned out to be a 1330 series u-joint afterall. But it was a good learning experience. Thanks for the help and feedback everyone.
__________________

1980 GMC C10 Pickup - SBC 350/Muncie SM465
A slow work in progress!
Kutzy is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 04:24 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com