90 degree offset u joint caps?? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum

Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 01-28-2004, 08:07 AM
Join Date: Dec 2003
Location: canton, ohio
Age: 48
Posts: 62
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
90 degree offset u joint caps??

Hello I ran across this one and do not understand it...."a common mistake made on multiple piece driveshafts especially the early gm 2 piece is phasing. The u joint caps must be turned exactly 90 degrees from the preceding driveline section" .......If they are talking about assembling the two sections together, then this does not apply to me since I am pretty positive that the two sections will only go together one way., if thats not what this person is talking about then I am clueless

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 01-28-2004, 08:57 AM
Last wiki edit: Crankshaft Coalition Wiki Last photo:
Join Date: Nov 2003
Location: Mid-Michigan
Posts: 2,097
Wiki Edits: 1

Thanks: 17
Thanked 155 Times in 144 Posts
This has to do with u-joint orientation or phasing which is an effect of the amount of angular displacement the u-joints will see. Putting them out of phase by 90 degrees allows the joints to go through the driveshafts rotational (angular) displacement without binding. This is applicable if you are building a NEW driveshaft. If you are just rebuilding one all of this has been taken into consideration and all you need to do is put it back together...
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 01-28-2004, 09:02 AM
M&M CUSTOM's Avatar
Hotrodders.com Moderator
Last wiki edit: Transmission identification
Last journal entry: 1988 Suburban, the project continues.
Last photo:
Join Date: Mar 2003
Location: Northwest Pennsylvania.
Age: 44
Posts: 2,236
Wiki Edits: 9

Thanks: 0
Thanked 2 Times in 1 Post
Your U-joints should always be in the same plane as each other, and on a single tube driveshaft either with, or without a slip yoke.

That statement is also meant for driveshafts that include a carrier bearing in the center of multiple shaft assemblies, mostly in limousines, pick-up trucks and larger vehicles, where a single tube driveshaft would be too long and heavy to make it practical.

Sometimes the tube sections can be splined together in a way that doesn't keep the U-joints in the same plane for example ++x or x+x, as opposed to the joints in plane XXX, or +++.

Having the joints in the same plane as each other reduces premature wear, and certain driveline noises.

This whole subject is not a problem if you are NOT building your own driveshafts, any competant driveline shop already knows this information.

Last edited by M&M CUSTOM; 01-29-2004 at 03:05 PM.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 01-28-2004, 07:29 PM
Last photo:
Join Date: Oct 2002
Location: Newport News, VA
Posts: 3,220
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Unless it is a 2 piece drive shaft set-up with splined shaft where they go together, and they are taken apart and put back together it should not be a problem. They can be put back together wrong in some cases. Like M&M said, any competant shop should know how they should go together if they are building one.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 01-29-2004, 10:29 AM
Jmark's Avatar
Last photo:
Join Date: Sep 2003
Location: phoenix
Age: 62
Posts: 5,033
Wiki Edits: 0

Thanks: 124
Thanked 103 Times in 83 Posts
In my Chevy truck book, it states to rotate the rear section of my 2 piece drive shaft 3 splines clockwise before installing. This will put the front and rear sections out of "phase" as has been discussed earlier. They go on to explain why they want it that way, but I don't do it.

As stated earlier, MOST slip joints in 2 piece shafts only go together one way, and the driveshaft shop usually puts all the u-joints in the same alignment. BUT!!! If you get a new slip joint, as I recently did, it may NOT be "keyed" to go together only one way, and must be marked before pulling it apart so the shaft stays in the same orientation as it was when balanced.
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos
Gear in this thread - Powered by O'Reilly Auto Parts

Quick Reply

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -6. The time now is 10:51 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.