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

high pitched hum in fzj80

Discussion in '80-Series Tech' started by AZcruiser, Jun 24, 2003.

  1. AZcruiser

    AZcruiser

    Messages:
    332
    Likes Received:
    0
    Joined:
    Jun 24, 2003
    Location:
    phoenix
    At highway speeds(60-75mph) I have a loud high pitched "hum". The sound drowns out around 80mph, and continues when accelerator is depressed. LTX Mich tires are in OK shape. Figuring its the wheel bearing(s), could it be other,i.e. driveline play, centerbearing?? I have the usual 80s thud upon accelerating, etc.etc. approx. 130k miles but well kept!
    Any suggestions to look for before pulling the wheel apart and replacing bearings.

    Thanks
    chris
     
  2. Scamper

    Scamper

    Messages:
    1,460
    Likes Received:
    2
    Joined:
    Mar 28, 2003
    Location:
    Somewhere in NJ
    Usual 80s thud on acceleration???? I don't have that. Am I missing something? Could that be a motor mount?

    The hum might be wheel bearings. When did you last service front end (assuming it's coming from front)? Does the sound change/disappear if turning left or right on a curve?

    Tom
     
  3. AZcruiser

    AZcruiser

    Messages:
    332
    Likes Received:
    0
    Joined:
    Jun 24, 2003
    Location:
    phoenix
    Thud meaning driveline play, i.e. letting off accelerator around 25-30 mph and/or slight thud after letting off brake at stop.
    Well I dont dare to turn at high speeds in the LC, but it is loud at 65+. Other than that it drives fine, other than typical "thudding" - worn diff. I have not serviced the front end and have a good feeling it wasnet done before I purchased it. My guess its the wheel bearings, planning on doing ths anyway but hoping for someone to offer pinpoint answer.

    chris
     
  4. Beowulf

    Beowulf

    Messages:
    12,534
    Likes Received:
    30
    Joined:
    Mar 27, 2003
    Location:
    Somewhere in the foothills...
    Chris,

    >> approx. 130k miles <<
    >> I have not serviced the front end and have a good feeling <<
    >> it wasnet done before I purchased it. <<

    Do it soon or your good feeling will quickly turn to a bad feeling.

    -B-
     
  5. cruiserman

    cruiserman

    Messages:
    1,861
    Likes Received:
    0
    Joined:
    Mar 27, 2003
    You're the only one that can do that. Pull the hubs and take a look at the bearings. That would be my first move.
     
  6. AZcruiser

    AZcruiser

    Messages:
    332
    Likes Received:
    0
    Joined:
    Jun 24, 2003
    Location:
    phoenix
    Thanks forthe input so far. Out at lunch today I tried to zero in on the noise, at lower speeds 15-25mph its sounds more like a winding noise from the front. Not sure if this is contibuting to the louder hum at higher speeds.
    If bearings are it I will replace the rear too, not sure if its floating or semi floating rear axel. Its a later year 94 w/ rear drum brakes, how to find out??
    Thanks
     
  7. cruiserdan

    cruiserdan SupportingVendor Emeritus Supporting Vendor Moderator

    Messages:
    20,605
    Likes Received:
    2,983
    Joined:
    Mar 27, 2003
    Location:
    Surrounded by Cruisers from all over the world
    Drums in the rear = semi-floating axle, no ABS.
     
  8. firetruck41

    firetruck41

    Messages:
    5,732
    Likes Received:
    10
    Joined:
    Mar 27, 2003
    Location:
    Camas, WA USA
    That's interesting, I thought 93 and newer (US) models were all full floaters with rear discs and ABS, except for a few early 93's that still had rear semifloater and drums. My 93 has full floater, rear discs and ABS. Seems like your 94 may be an anomoly?
     
  9. cruiserdan

    cruiserdan SupportingVendor Emeritus Supporting Vendor Moderator

    Messages:
    20,605
    Likes Received:
    2,983
    Joined:
    Mar 27, 2003
    Location:
    Surrounded by Cruisers from all over the world
    Ben,

    Strickly speaking the FFA and ABS were optional in both 93 and 94. They did not become standard equipment until the 95 model year.(in the US anyway). There were a few 93-94 vehicles that snuck through without ABS and FFA if the people at TMS fell asleep at the stick when they were checking the little order boxes. I have seen one 93 that did not have it. That one came from Texas where the distributor for Toyota is an independent. I have also seen a couple from that direction with no sunroofs and a couple without 3rd seats.

    Dan
     
  10. landtoy80

    landtoy80

    Messages:
    5,668
    Likes Received:
    241
    Joined:
    Mar 13, 2003
    Location:
    North Front Range, CO
    I have the same hum. I replaced all bearings and birfields and diff bearings. I have new T-case, u-joints and the only think I have yet to do is the rear axle bearing and diff. When I had the front driveshaft off, there was no hum. I think it is the vib of the driveshafts sending power back and forth to the rear and front. Hay at least have a theory 8)
    I also have the thump when i second gear (at slower speeds) and ,let off the throttle, it thumps into first. I played with the throttle cable with no luck
    :'(
    kurt
     
  11. cruiserdan

    cruiserdan SupportingVendor Emeritus Supporting Vendor Moderator

    Messages:
    20,605
    Likes Received:
    2,983
    Joined:
    Mar 27, 2003
    Location:
    Surrounded by Cruisers from all over the world
    Sometimes you can get a high pitched whine out of the passenger seat..... Oh, wait. That's something else............................... ::)
     
  12. Junk

    Junk

    Messages:
    6,185
    Likes Received:
    23
    Joined:
    Dec 13, 2002
    Location:
    buggerville nj
    Haven't had a hum in my 80 yet, marriage does that though. :flipoff2: :wannabob: :D
     
  13. Photoman

    Photoman SILVER Star

    Messages:
    1,145
    Media:
    41
    Likes Received:
    47
    Joined:
    Mar 28, 2003
    C-Dan,
    You're right! I always get a whine from the passenger side that's something else - the refrigerator. ::)
    Bill
     
  14. cruiserdan

    cruiserdan SupportingVendor Emeritus Supporting Vendor Moderator

    Messages:
    20,605
    Likes Received:
    2,983
    Joined:
    Mar 27, 2003
    Location:
    Surrounded by Cruisers from all over the world
    Bill, I believe you ment to say "high priced wine" 8)