NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > OEM Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

OEM Tech Discussion Forum for OEM (Original Equipment) or stock XJs and MJs.

Reply
 
Thread Tools Display Modes
  #1  
Old August 23rd, 2017, 22:01
4x4JeePmaNthINg's Avatar
4x4JeePmaNthINg 4x4JeePmaNthINg is offline
NAXJA Forum User
 
Join Date: Nov 2008
Location: colorado, Foco
Posts: 442
Front drive shaft VIBES

99 auto 242 re3.5sf 33nitto...

My front drive shaft has bad VIBES at high speed 70mph 3000rpm abouts. I pulled it and went for a test drive, VIBES gone.

I've had the lift for years and it's always had VIBES, but I think it's the stock shaft. It's a little more noticeable now because I'm a 4.56 gears so I get VIBES at lower speed, same rpm...

How smooth should the double cardan/ centering ball section rotate. Is this difficult to replace with out a vice?

Ive replaced all other xj u joints but never centering ball and such.

Do drive shaft themselves wear Out?

194000, I checked for play, the cardan feels kinda notchy and at this point I don't want to explode all that crap until I know if it's worth digging into vs new/ modified current shaft cost.

Whatchyall got for wisdom?
Thank you
Reply With Quote
  #2  
Old August 24th, 2017, 02:58
Jim Malcolm Jim Malcolm is offline
NAXJA Forum User
 
Join Date: Aug 2014
Location: PA
Posts: 22
Re: Front drive shaft VIBES

I'm at ~4" lift with aftermarket fixed LCAs and a NP242 in my '94 XJ and I had to get a longer front driveshaft. Prior to realizing that, I had the OEM one straightened, balanced and rebuilt with very little change, both remaining in my wallet and in vibration.

The OEM shaft has 3" of travel and I took that to be measurable between the the two sections (bottomed out is one end of that 3"). By that measure I had around 3/4" of travel remaining at ride height. The measurement I gave when ordering a longer one was just under 2" longer than the OEM spec (32.5" vs 30.66"). Now it's smooth as butter at any speed with a SYE in the rear. I spent nearly as much getting the OEM shaft straightened, balanced and rebuilt as I did on a new shaft with all the goodies.
Reply With Quote
  #3  
Old August 24th, 2017, 06:47
md21722 md21722 is offline
NAXJA Member
 
Join Date: Feb 2014
Location: Colorado Springs
Posts: 2,294
Re: Front drive shaft VIBES

The double cardan should move around pretty smoothly without looseness or excessive roughness. A vice is not needed to change the double cardan parts.

The slip joint can and does wear and that can cause vibrations but how much has to do with the individual vehicle & probably how much slop is in your transfer case front output shaft.

A driveshaft that is out of balance or bent will cause vibrations too.

Any decent shop will redo the double cardan and balance for about half of what a new driveshaft costs. If the slip joint is bad the repair cost is about the same as a replacement shaft.

I've heard good things about the driveshaft shop in Greeley.
Reply With Quote
  #4  
Old August 24th, 2017, 09:42
4x4JeePmaNthINg's Avatar
4x4JeePmaNthINg 4x4JeePmaNthINg is offline
NAXJA Forum User
 
Join Date: Nov 2008
Location: colorado, Foco
Posts: 442
Re: Front drive shaft VIBES

would any slop on the TC output be noticeable by hand?
Reply With Quote
  #5  
Old August 24th, 2017, 09:51
md21722 md21722 is offline
NAXJA Member
 
Join Date: Feb 2014
Location: Colorado Springs
Posts: 2,294
Re: Front drive shaft VIBES

Quote:
Originally Posted by 4x4JeePmaNthINg View Post
would any slop on the TC output be noticeable by hand?
Yeah. Just tug up and down on the yoke. They all have some slop as far as I know. Some slop in the slip joint isn't going to cause major problems either. If the vibes you're feeling are 100% of the time its probably a bent/balance. Most of the other causes kind of come and go as you drive.
Reply With Quote
  #6  
Old August 24th, 2017, 12:32
4x4JeePmaNthINg's Avatar
4x4JeePmaNthINg 4x4JeePmaNthINg is offline
NAXJA Forum User
 
Join Date: Nov 2008
Location: colorado, Foco
Posts: 442
Re: Front drive shaft VIBES

the slip pretty much slides apart on its own if i hold the drive shaft up, and i had greased it a month ago. it would probably stay put with fresh grease but something is giving the shaft bad vibes. ill check the TC output. this shaft again is stock so i imagine vibes could be from wear. the front pinion angle isnt too bad with fixed LCAs and the 3.5 lift.
Reply With Quote
  #7  
Old August 24th, 2017, 12:49
md21722 md21722 is offline
NAXJA Member
 
Join Date: Feb 2014
Location: Colorado Springs
Posts: 2,294
Re: Front drive shaft VIBES

To see how much slop is in the slip joint pull and push it side to side, or hold the long end of the driveshaft down and push up and down on the yoke end that connects to the axle.
Reply With Quote
  #8  
Old August 24th, 2017, 13:52
RCP Phx RCP Phx is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 10,646
Re: Front drive shaft VIBES

Quote:
Originally Posted by 4x4JeePmaNthINg View Post
the front pinion angle isnt too bad with fixed LCAs and the 3.5 lift.
What does that mean? The pinion should point at the driveshaft "as best as possible"!
Reply With Quote
  #9  
Old August 24th, 2017, 19:40
4x4JeePmaNthINg's Avatar
4x4JeePmaNthINg 4x4JeePmaNthINg is offline
NAXJA Forum User
 
Join Date: Nov 2008
Location: colorado, Foco
Posts: 442
Re: Front drive shaft VIBES

Quote:
Originally Posted by RCP Phx View Post
What does that mean? The pinion should point at the driveshaft "as best as possible"!
Yes and it does within reason , Fixed Lca/ uca it is pretty straight though.
Reply With Quote
  #10  
Old August 24th, 2017, 20:54
lawsoncl lawsoncl is offline
NAXJA Forum User
 
Join Date: Jan 2006
Location: North Idaho
Posts: 4,574
Re: Front drive shaft VIBES

Quote:
Originally Posted by 4x4JeePmaNthINg View Post
Yes and it does within reason , Fixed Lca/ uca it is pretty straight though.

Fixed knuckles too, so rotating means changing the caster
Reply With Quote
  #11  
Old August 25th, 2017, 00:09
4x4JeePmaNthINg's Avatar
4x4JeePmaNthINg 4x4JeePmaNthINg is offline
NAXJA Forum User
 
Join Date: Nov 2008
Location: colorado, Foco
Posts: 442
Re: Front drive shaft VIBES

Quote:
Originally Posted by lawsoncl View Post
Fixed knuckles too, so rotating means changing the caster
yes, but what are you getting at for the DS. im not clocking knuckles???

any lift will change Factory settings, however up to a point most lift sizes are passable for driveability. sure i would like to be able tune every welded bracket to the geometry, but i havent that ability. not sure if this is what your getting at?
Reply With Quote
  #12  
Old August 25th, 2017, 06:02
RCP Phx RCP Phx is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 10,646
Re: Front drive shaft VIBES

That could be your issue though, What's the pinion angle? What's your driveshaft angle? What's your caster angle? A set of adj uppers could easily fix the problem!

Without that info this thread is "Pointless"!

Last edited by RCP Phx; August 25th, 2017 at 06:15.
Reply With Quote
  #13  
Old August 25th, 2017, 08:55
lawsoncl lawsoncl is offline
NAXJA Forum User
 
Join Date: Jan 2006
Location: North Idaho
Posts: 4,574
Re: Front drive shaft VIBES

Quote:
Originally Posted by 4x4JeePmaNthINg View Post
yes, but what are you getting at for the DS. im not clocking knuckles???

any lift will change Factory settings, however up to a point most lift sizes are passable for driveability. sure i would like to be able tune every welded bracket to the geometry, but i havent that ability. not sure if this is what your getting at?
Just pointing out that changing the pinion angle on the front diff means changing your caster unless you're planning to get out the welder and rotate the axle tubes.

More than likley it's bad u-joints or a sloppy slip yoke (exacerbated by a lift that has it more extended than normal)
Reply With Quote
  #14  
Old August 25th, 2017, 11:41
RCP Phx RCP Phx is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 10,646
Re: Front drive shaft VIBES

He's probably got to much camber now! On a factory 4-link, as the suspension is lifted the pinion rolls down and caster increases.
Reply With Quote
  #15  
Old August 25th, 2017, 12:32
4x4JeePmaNthINg's Avatar
4x4JeePmaNthINg 4x4JeePmaNthINg is offline
NAXJA Forum User
 
Join Date: Nov 2008
Location: colorado, Foco
Posts: 442
Re: Front drive shaft VIBES

if thats the case, if, then i can only fix the vibes with adjustable LCA/UCA right.

i dont have an angle finder, but i can try puting one on the phone and see if i can report back something that makes sense. where should i take the angle from the drive shaft, anywhere flat? the pinion yoke angle should be easy to measure i hope.
Reply With Quote
Reply


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

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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Front drive shaft vibes muddypunk NorthWest Chapter 10 August 12th, 2011 11:15
Drive shaft vibes? crux12 Modified Tech Discussion 3 October 20th, 2010 07:28
front d-shaft vibes bcmaxx OEM Tech Discussion 3 July 23rd, 2007 18:35
front drive shaft vibes etaniyani Modified Tech Discussion 12 October 3rd, 2006 00:13
Drive shaft vibes (front vs. rear) dphillips Modified Tech Discussion 6 December 16th, 2004 17:11


All times are GMT -7. The time now is 15:40.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014