CJ--Driveline angles with approx 2.5" spring lift? - Off-Road Forums & Discussion Groups
Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK

 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 09-07-2002, 06:56 PM Thread Starter
 
Join Date: Oct 2001
Posts: 1,720
Thanks: 0
Thanked 0 Times in 0 Posts
 
CJ--Driveline angles with approx 2.5\" spring lift?

Okay, I have a vibration in my drivetrain. Neither I nor my father (over 40 years experience as a mechanic) can find the little beggar. It feels like the rear driveline or rearend. Shifting the transfer case into 2hi, 4hi or 4lo makes no difference. It happens in all gears. We tore the rearend down today (factory D44 trac loc 3.73 in a '74 CJ5), only thing we found that looked questionable was that we had the bearings on the ring gear a hair too tight--we removed a shim and put everything back together--and it still has the vibration. We tried putting the jeep on jackstands, and placed a hydraulic jack under the front of the diff. We put it in gear, and then lifted up on the jack...the vibration lessened. We are thinking that possibly we need to rethink the angle on the pinion shaft. Before we go crazy and start playing with shims, does anyone know what the angle was from the factory? And was it measured off the frame? Ground? or???? I'm running 33" tires and the lift is re-arched springs with an add-a-leaf for a total lift of approx 2.5". I'm not overly sharp on driveline angles, so any advice (heck or any advice on something I might have overlooked on the vibration!) would be greatly appreciated.
cj5_pilot is offline  
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 09-07-2002, 08:29 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Re: CJ--Driveline angles with approx 2.5\" spring lift?

<blockquote><font class="small">In reply to:</font><hr>

only thing we found that looked questionable was that we had the bearings on the ring gear a hair too tight--we removed a shim and put everything back together--and it still has the vibration.

<hr></blockquote>

This doesn't address the question, but it still is an issue. If you removed a carrier bearing shim you have now changed not only the bearing preload but also the R&amp;P backlash, I sure hope you checked the backlash after removing the shim.
post #3 of (permalink) Old 09-07-2002, 09:43 PM
Tinman
Guest
 
Posts: n/a
Re: CJ--Driveline angles with approx 2.5\" spring lift?

According to the '74 FSM, you place a bubble protractor on the frame rail and place shims under the tires to level it. Then it says to check the pinion angle using a bubble protractor by taking a reading from the cover face of the differential housing or removing the cover and take the reading from the machined surface. Unfortunately, the manual only shows pinion angles for the Wagoneer, Cherokee and the J series trucks. Mine is currently in pieces, so I can't measure it for you.
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 09-07-2002, 10:00 PM
 
Join Date: Jul 2002
Posts: 111
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: CJ--Driveline angles with approx 2.5\" spring lift?

Here's a site that covers the subject pretty good. Its really not that difficult once you understand the basic's.

http://www.4xshaft.com/

Basically if your transfer case out put is down 4, 6, 8 degrees then your rear pinion shaft needs to be up a like amount or with in a degree or two.

Good Luck

Loafer409 is offline  
post #5 of (permalink) Old 09-07-2002, 10:21 PM Thread Starter
 
Join Date: Oct 2001
Posts: 1,720
Thanks: 0
Thanked 0 Times in 0 Posts
 
Sometimes it\'s simple things that bite your butt

Well it WASN'T the driveshaft angle.....the driveline yokes were out of phase! We hadn't ever taken the slip yoke off the rest of the driveline since it had the little retainer ring on it....and it was 90 degrees out of phase! The jeep probably had the vibration last year when I bought it, but there were enough other problems that I could have attributed the vibration too I never really thought about it. Now that everything is getting pretty close to "great", the vibration became a major headache. The ujoints rolled okay and had no adverse movement, but when we took the caps off there was some galling inside. We slapped on a pair of new u-joints and got the yokes in phase and PRESTO! no vibration.....and here we were concocting more and more elaborate theories as to what was wrong.....live and re-learn I guess! Thanks everybody who responded!

Brad--the bearing preload was WAY too much, that's why we dropped a shim. We did check the backlash again, and it was actually a bit better--it also was a hair on the tight side before. Thanks for mentioning it though, 'cause after a bone headed move like not noticing the position of the yokes I'm not sure I'm positive of which is the brake and gas 'about now.....*grin*

Tinman--thanks for the technique. I'm STILL going to check the angles just to have my ducks in a row!.

Loafer409--That's the link I found to day. I was just reading the part about yokes being in phase when my dad hollered he had an idea as to what might be wrong....great minds think alike I guess! Thanks though, that is a great site!
cj5_pilot is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Off-Road Forums & Discussion Groups 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 email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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
Trackbacks are On
Pingbacks are On
Refbacks are On

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