quick question rear axle - JeepForum.com
 
LinkBack Thread Tools
post #1 of 15 Old 09-10-2021, 03:43 PM Thread Starter
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 6,689
quick question rear axle

I was messing with my brakes today, and I noticed that the axle shaft (non C clip) has a little bit of end play (maybe .030). No other signs of trouble (noise, leakage, no radial play). Is this typical? Bearings were replaced a few years ago.


My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
Sponsored Links
Advertisement
 
post #2 of 15 Old 09-11-2021, 01:32 AM
YJ40
Registered User
 
YJ40's Avatar
1989 YJ Wrangler 
 
Join Date: Feb 2009
Posts: 36
Check the mounting plate behind the bearings, with the 4 boltholes,sometimes they bend...
Attached Images
 

89´YJ 4.6l
94´YJ 4.0l
YJ40 is offline  
post #3 of 15 Old 09-11-2021, 03:47 AM Thread Starter
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 6,689
Quote:
Originally Posted by YJ40 View Post
Check the mounting plate behind the bearings, with the 4 boltholes,sometimes they bend...
I've not seen the bearing. Is it a straight roller bearing? I'm guessing it's not tapered or ball?

My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
 
post #4 of 15 Old 09-11-2021, 03:52 AM
YJ40
Registered User
 
YJ40's Avatar
1989 YJ Wrangler 
 
Join Date: Feb 2009
Posts: 36
Non c-clip should look like this...
Attached Thumbnails
IMG_20210911_115019_5_1631353907613.jpg  

89´YJ 4.6l
94´YJ 4.0l
YJ40 is offline  
post #5 of 15 Old 09-11-2021, 04:13 AM
YJ40
Registered User
 
YJ40's Avatar
1989 YJ Wrangler 
 
Join Date: Feb 2009
Posts: 36
Installed you cant see the bearing,only the retaining plate with 4 bolts.

89´YJ 4.6l
94´YJ 4.0l
YJ40 is offline  
post #6 of 15 Old 09-11-2021, 06:15 AM Thread Starter
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 6,689
Quote:
Originally Posted by YJ40 View Post
Non c-clip should look like this...
thanks

My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
post #7 of 15 Old 09-12-2021, 01:43 PM
fishadventure
Web Wheeler
 
fishadventure's Avatar
1989 YJ Wrangler 
 
Join Date: Jul 2013
Location: Morrisville
Posts: 9,425
Garage
Quote:
Originally Posted by jay-h View Post
I was messing with my brakes today, and I noticed that the axle shaft (non C clip) has a little bit of end play (maybe .030). No other signs of trouble (noise, leakage, no radial play). Is this typical? Bearings were replaced a few years ago.
I don’t think 030 is an issue.
I actually don’t recall if there’s a spec but that would seem normal to me, eh, @Boojo35 ?

[size=“3”]Shackles & D-rings are different things.
Cranking IS turning over
fishadventure is offline  
post #8 of 15 Old 09-13-2021, 05:52 AM Thread Starter
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 6,689
Quote:
Originally Posted by fishadventure View Post
I don’t think 030 is an issue.
I actually don’t recall if there’s a spec but that would seem normal to me, eh, @Boojo35 ?
Sounds good, I'm thinking that it might be ok.. For all I know it could have been this way for years. I will have my mechanic guy take a look today. (I'll be taking it on a bit of a trip at the end of the month, so that's why I'm checking so carefully)

My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
post #9 of 15 Old 09-13-2021, 06:24 AM Thread Starter
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 6,689
I talked to the mechanic. He said that a little end play was common in these, not really a worry.

My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
post #10 of 15 Old 09-18-2021, 01:52 AM
80cj
Web Wheeler
 
80cj's Avatar
1980 CJ5 
 
Join Date: May 2002
Location: Hawaii
Posts: 8,785
My Friend has a 94 (I believe) and we could grab the rollbar and shove sidewards back and forth and hear the axles making a clunking sound against the thrust block in the diff. Did that off road too. No harmful effects that we could notice.
80cj is offline  
post #11 of 15 Old 09-21-2021, 03:02 AM
YJ40
Registered User
 
YJ40's Avatar
1989 YJ Wrangler 
 
Join Date: Feb 2009
Posts: 36
Non c-clip axles have tapered roller bearing. C-clip axles have different bearing design,cylindrical roller (like your friends 94), so end play is not big problem.
On a tapered roller bearing every little play reduces the contact surface and leads to wear.
The more play,the less contact surface...

89´YJ 4.6l
94´YJ 4.0l
YJ40 is offline  
post #12 of 15 Old 09-21-2021, 06:07 PM
Boojo35
Registered User
1987 YJ Wrangler 
 
Join Date: Jul 2007
Location: Beer City
Posts: 3,284
Garage
I have popped in and out on this thread a few times and tried to find a spec for this. I cannot find one and if anybody could, I have a chance of being that guy. It is how I roll. Being that the axle bearing is tapered as @YJ40 mentioned, it should be pretty damn tight. I fully agree that the mounting plates will probably bend with normal wear and tear and should be replaced. Tapered roller bearings need preload for the reasons he stated. My experience tells me that they are more forgiving when on the looser side like in certain uses like the front brake rotors on older RWD vehicles. However. Differential pinion bearing preload is a place where it will bite you in the a$$ quickly. There is probably more deflection there than in any other place due to gear ratios and their effects on leverage. Differentials are what really taught me the importance of preload on tapered bearings. Play in them is just not a good thing. The bearing no longer works as designed and actually fails very quickly in some instances.

If you cannot fix it with a hammer then it has to be an electrical problem.
Boojo35 is offline  
post #13 of 15 Old 09-22-2021, 07:02 AM Thread Starter
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 6,689
Quote:
Originally Posted by Boojo35 View Post
I have popped in and out on this thread a few times and tried to find a spec for this. I cannot find one and if anybody could, I have a chance of being that guy. It is how I roll. Being that the axle bearing is tapered as @YJ40 mentioned, it should be pretty damn tight. I fully agree that the mounting plates will probably bend with normal wear and tear and should be replaced. Tapered roller bearings need preload for the reasons he stated. My experience tells me that they are more forgiving when on the looser side like in certain uses like the front brake rotors on older RWD vehicles. However. Differential pinion bearing preload is a place where it will bite you in the a$$ quickly. There is probably more deflection there than in any other place due to gear ratios and their effects on leverage. Differentials are what really taught me the importance of preload on tapered bearings. Play in them is just not a good thing. The bearing no longer works as designed and actually fails very quickly in some instances.
The weird thing is, there seems no mechanism for adjusting a preload here. No wheel nut (and usually preloaded tapered bearings are mounted in opposite pairs), just a non precision plate which sandwiches the bearing between the oil seal on one side and the pressed on collar on the other. That's kind of all there is. In actual fact, unless I am really missing something, the only thing holding the axle in place is a pressfit between the inner race and the axle.

My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
post #14 of 15 Old 09-22-2021, 12:41 PM
80cj
Web Wheeler
 
80cj's Avatar
1980 CJ5 
 
Join Date: May 2002
Location: Hawaii
Posts: 8,785
Tapered roller bearings don't necessarily require preload. A good example is the tapered roller bearings used in tapered axle setups like stock AMC 20's and Dana 44's as used in early CJ's. In these axles there is a .004-.006 endplay spec that must be adhered to. When properly installed, you can grab the axle shaft and actually shake it up and down/ shove it in and out a minute amount. This endplay spec takes into account expansion of axle shafts from temperature and prevents the bearings from being overloaded due to thermal expansion. In differential setups carrier bearings and pinion bearings are given a pre-determined amount of preload to control gear deflection and compensate for wear, thermal expansion. Further, differentials are constantly bathe in a fairly large amount oil which helps keep temperatures under control.

The OP's bearings I think are set 9. This bearing type is self a contained unit bearing. In installation, the bearing is captured in the housing bearing cavity and the bearing controls end play within itself since the unit bearing has a "rib ring" to control end play on the non tapered side (that faces the axle flange) Because the bearing contains end play, the axle shaft is allowed to float in the differential, unlike the later C clip setup that needs a thrust block and C clip to retain the axle and control end play. I think .030 endplay in the OP's bearing is a little excessive. Compare it with a new bearing.
Attached Images
 
80cj is offline  
post #15 of 15 Old 09-22-2021, 05:17 PM
Boojo35
Registered User
1987 YJ Wrangler 
 
Join Date: Jul 2007
Location: Beer City
Posts: 3,284
Garage
@80cj I will totally buy into your explanation. Most of my diff experience is with c-clip type or full floaters as in tons. I know that you are a knowledgeable and competent diff guy. Thanks for sharing your knowledge.

If you cannot fix it with a hammer then it has to be an electrical problem.
Boojo35 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome