1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

slack in rear diff

Discussion in '80-Series Tech' started by ginericLC, Mar 10, 2004.

  1. ginericLC

    ginericLC Wagon Wheeler! SILVER Star

    Messages:
    7,077
    Likes Received:
    296
    Joined:
    Jan 29, 2003
    Location:
    MH, IDaho
    I've been trying to lessen my clunk a little bit. I pulled the rear driveshaft last night and I noticed that the rear diff turns quite a bit before it engages the axles. Could this be caused by a worn out ring and pinion?
     
  2. Bradass80

    Bradass80

    Messages:
    220
    Likes Received:
    0
    Joined:
    Jul 24, 2003
    Location:
    Colorado
    I hope somone has some good info on this aswell, i have quite a bit of clunkage in my rear end also, i think some of it is that i have a powertrax in there too, Brad.
     
  3. ginericLC

    ginericLC Wagon Wheeler! SILVER Star

    Messages:
    7,077
    Likes Received:
    296
    Joined:
    Jan 29, 2003
    Location:
    MH, IDaho
    I'm going ARB and I'm concerned that I might need a new ring and pinion to get it set up tight. Not something I want to buy right now. Yesterday, I had two flat tires. My luck is not going so well. On Sunday, I broke my antenna when I was trying to remove it to replace a broken mast. I'm just having a string of bad luck.
     
  4. yomama

    yomama

    Messages:
    291
    Likes Received:
    0
    Joined:
    Mar 27, 2003
    This is NOT 100%, but I believe typically you should be able to rotate your drive shaft 1/2 turn from tight one way to tight the other way. Someone please correct me if I am wrong. WHEN you do install the ARB you will need to know how to set the backlash correctly. I read over the FSM, I even had the gauge, not the paint or chalk they suggested, but I was still leary enough AFTER I did it, that I took it in to a shop and had them double check my backlash, surprisingly they said I had it pretty close. Still, I felt better...

    Yomama
     
  5. Cruiserdrew

    Cruiserdrew SILVER Star

    Messages:
    14,607
    Likes Received:
    3,035
    Joined:
    Mar 15, 2003
    Location:
    Sacramento, CA
    It looks weird but a fair amount of backlash is normal. Also when things wear it is rarely the ring and pinion-much more likely to be the support bearings. Does it make any noises? Especially howling when decellerating from speed, or growling when turning corners? I just went through this on my FJ60-the local diff guy at River City Differentials is a Toyota off-road guy. I had a bad howl on decelleration. I pulled the diff, took it to him and he said the R&P were in perfect condition, so he rebuilt it with new bearings and it is nice and tight-totally cured my problem. You may be able to do something similar and save some major $, especially since the rear is pretty easy to get out. If your diff is quiet, and there isn't abnormal amounts of metal on the drain plug, I would run it and forget about it. Next time you pull the shafts for a wheel bearing repack, pull the diff and let a pro check it out.
     
  6. ginericLC

    ginericLC Wagon Wheeler! SILVER Star

    Messages:
    7,077
    Likes Received:
    296
    Joined:
    Jan 29, 2003
    Location:
    MH, IDaho
    It is my 91 so I don't have to repack the rear wheel bearings. When I set up the ARB I'm actually not doing it myself really. I have a friend who is really good at setting them up. He even has an old housing on stand that he bolts it to to work on it so it at a nice height. Maybe since I'm doing the bearings with the ARB some of the slack will go away. The slack is not in the driveshaft but in the actual rearend. Also, when I pulled the driveshafts I noticed that the front output has more slack than the rear. I thought this might be normal as the front might need a bit more for turning. Am I correct or do I just have uneven wear. I'm not overly concerned about this too much as I've driven other Cruisers with more of a clunk and they seem to be OK for several thousand more miles without issues.
     
  7. Bob_Garrett

    Bob_Garrett

    Messages:
    1,195
    Likes Received:
    3
    Joined:
    May 17, 2003
    Location:
    Irving, TX
    I regeared mine last year and the guy who set up the gears said that the old gears looked good and had an excellent pattern. This was at about 120k mi. Installed new Yukon gears and initially it seemed as though the clunking was reduced, but after a year, it seems about the same as before. No other unusual noises.

    Nature of the beast, I quess.

    Bob
     
  8. Pitbull

    Pitbull

    Messages:
    682
    Likes Received:
    2
    Joined:
    Oct 31, 2003
    [quote author=Bradass80 link=board=2;threadid=12868;start=msg118534#msg118534 date=1078938902]

    I hope somone has some good info on this aswell, i have quite a bit of clunkage in my rear end also. Brad.

    [/quote]

    I suggest you eat more fiber. I add about 6 OZ's of uncooked oatmeal to my protein shake every morning and my rearend does not clunk, it spew's :flipoff2:
     
  9. landtank

    landtank SILVER Star

    Messages:
    18,893
    Likes Received:
    1,020
    Joined:
    Mar 27, 2003
    Location:
    Groveland MA
    I checke d this on my truck a year or so ago. If I turned the flange in one direction til it stopped, marked it and rotated it in the other direction til it stopped there would be about a Half inch distance between the 2. This is with 4.88s. Becasue of the pitch difference with stock 4.10s it would be slightly less.
     
  10. robbie

    robbie Guest

    You will not really be able to tell if the ring and pinion are good until you pull the diff cover to inspect them(if this is the 91 other wise you will have to pull the diff to see). I would guess that the ring and pinion are good but the bearings may have some wear creating more back lash then what is reccomended upon set up (.008). When putting in the ARB you might what to replace all the bearings so you would not have to worry about them in the future. later robbie
     
  11. montocr

    montocr

    Messages:
    294
    Likes Received:
    1
    Joined:
    Oct 22, 2003
    Location:
    north of seattle
    When you turn the pinion flange you are feeling the slack in the spider gears, crosspin shaft, axle splines, backlash, etc. It all adds up and then is amplified by gear ratio. If there is enough backlash to create a noticable clunk, then the rearend would definately be howling. The spider gears and cross shaft wear can create this, but it is likely that you are experiencing the normal clunk associated with a fulltime 4wd vehicle. Also, the vehicle that has the powertrx is definately going to have clunks, as the teeth inside the unit require this in order to disengage.
    Carl
     
  12. trbrown

    trbrown

    Messages:
    26
    Likes Received:
    0
    Joined:
    May 30, 2003
    Location:
    Temple,Texas
    I also had "the clunk".Changed the dif fluid which looked new,no metal on the plug,I went with heavier fluid.The clunk is not as bad now.Im happy. :beer: