Transfer Box/Viscous Coupling - Grinding Noise & No Drive
  1. Welcome to RangeRovers.net – General discussion forum for Range Rovers

    Welcome to RangeRovers.net - a website dedicated to all things Range Rovers.

    You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, Join RangeRovers.net today!
     
Results 1 to 12 of 12

Thread: Transfer Box/Viscous Coupling - Grinding Noise & No Drive

  1. #1
    FRESHMAN ROVER knottinbots's Avatar
    Join Date
    March 25th, 2012
    Location
    Botswana
    Posts
    15

    Question Transfer Box/Viscous Coupling - Grinding Noise & No Drive

    Greetings all

    Search has been done but I haven't found anything with similar symptoms other than transfer chain failure, H-L shift movement failure, or viscous coupling failure in which the coupling locks up - none of which seem to be the case for me.

    Cause:
    • Driving normally, no unusual noises or vibrations, normal power levels, car has been driven regularly in the preceding weeks.
    • I had slowed down to ~30km/hr due to bad road conditions and when I applied power (maybe with a little vigour...) to resume cruising speed I lost all drive: engine running fine, just no forward movement and a rather nasty grinding/buzzing noise.
    • Managed to coast to a safe location, investigate and fail to resolve, recover home and investigate further.


    Effect:
    1. No movement regardless of gear selection
    2. All driveshafts intact
    3. Transfer box motor makes noise and instrument panel shows successful movement from H to L and back again
    4. A significant grinding noise in gear (D, R, 1, 2 3) that varies in speed depending on whether the transfer box is in H (high speed buzz/grind) or L (low speed buzz/grind)
    5. Grinding noise persists slightly when returning to neutral before quietening down
    6. Vehicle rolls freely when in gear (manual push 1-2m back and forth)


    The fact that the noise changes frequency depending on selection of H or L leads me to believe that the transfer mechanism still works, and that the problem lies on the output side of the transfer box.

    Has anybody experienced similar with a viscous coupling failure? The more common failure modes seem to be total lockup with resulting tyre squeal when cornering, or movement but in 2-wheel drive only.

    Thanks in anticipation.
    Quick reply to this message Reply  

  2. Remove Advertisements
    Range Rovers Forum
    Advertisements
     

  3. #2
    SOPHOMORE ROVER
    Join Date
    March 2nd, 2015
    Location
    tasmania australia
    Posts
    340

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    their is no 2 wheel drive with these vehicles , permanent 4wd only. put a fuse in the fuse slot to go into tow mode ( under seat not shore what number, in hand book )and run the box to see if the grinding is still there if so its not the transfer, just a process of elimination.
    Quick reply to this message Reply  

  4. #3
    JUNIOR ROVER
    Join Date
    October 17th, 2017
    Location
    East England
    Posts
    874

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Fuse 11 puts the transfer case into neutral, a position between high and low. The range change gears are before the chain and viscous coupling so if the noise goes away with it in neutral you've confirmed it down to the output side of the transfer case. Never heard of a chain breaking but I suppose it's possible and a viscous would usually lock up so you'd still have drive (and no noise). Looks like you'll be dropping the transfer case off. It's not actually difficult, although Rave says to remove the exhaust you don't need to, it'll come out with it still there and you can get to the top bolts with a couple of socket extensions and a knuckle joint. You'll need two people though as it's bloody heavy!
    96 4.6HSE
    98 4.0 Police spec
    and a number of others I maintain for the owners.
    Quick reply to this message Reply  

  5. Remove Advertisements
    Range Rovers Forum
    Advertisements
     

  6. #4
    FRESHMAN ROVER knottinbots's Avatar
    Join Date
    March 25th, 2012
    Location
    Botswana
    Posts
    15

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Thanks mad as, looks like I will be buying a new battery for that part of the diagnostic since the beast has been standing a while now.

    I know they are permanent 4x4, the 2-wheel drive reference is to cases where people have removed a prop-shaft under duress.
    Quick reply to this message Reply  

  7. #5
    FRESHMAN ROVER knottinbots's Avatar
    Join Date
    March 25th, 2012
    Location
    Botswana
    Posts
    15

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Thank you Richard G, as for my reply to mad as, I will organise a battery and do some diagnostics.

    I guess it is coming out regardless!

    Hopefully a trolley jack will be useful since I am short of helpers.
    Quick reply to this message Reply  

  8. #6
    SENIOR ROVER
    Join Date
    September 10th, 2007
    Location
    Chester, England
    Posts
    1,269

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    The transfer box weighs 75Kg, if that helps.
    2000 Range Rover 2.5 DSE HP24 auto, uprated torque converter - JFearn chip, larger intercooler, removable winch, stainless exhaust, alloy radiator, Gen III's, Terrafirma +2" shocks, GG AT2's. Faultmate MSV2. Land Rover folding mountain bike with 1000W electric motor.
    ex-1996 Discovery 2.5 300Tdi diesel auto
    ex-1982 Classic 3.86 Perkins diesel manual
    Quick reply to this message Reply  

  9. #7
    SOPHOMORE ROVER
    Join Date
    November 10th, 2016
    Location
    Tasmania
    Posts
    292

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Drive chain in TC snapped?
    Quick reply to this message Reply  

  10. #8
    JUNIOR ROVER
    Join Date
    August 2nd, 2007
    Location
    Southern California, USA
    Posts
    820

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Regarding removal of transfer case, I would not recommend use of a trolley jack. You should seriously consider investing in a scissor lift, so you can secure the transfer case and lower in a controlled manner.

    Also, when you say quiet down in neutral, does the grinding sound completely go away? If not, bad torque converter would give similar symptom.
    02 P38
    SoCal, USA
    Quick reply to this message Reply  

  11. #9
    SOPHOMORE ROVER
    Join Date
    November 10th, 2016
    Location
    Tasmania
    Posts
    292

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Can you move the vehicle when it's in park? Hand brake off.
    Quick reply to this message Reply  

  12. #10
    FRESHMAN ROVER knottinbots's Avatar
    Join Date
    March 25th, 2012
    Location
    Botswana
    Posts
    15

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Thanks all, and notes made on appropriate tools.

    My day job limits access to the vehicle, so apologies for huge length of time since last post.

    - in P with handbrake off the vehicle can be moved
    - in transfer neutral with fuse in and handbrake off:
    - there is no grinding in any transmission position with engine running
    - diagonal opposite wheels jacked the wheels turn freely by hand
    - front left wheel only raised will not rotate (within the limits of the force I felt comfortable applying: leaning hard on a ~1m extension, I realise I don't think I tried turning a rear wheel on its own)
    - there is a ticking noise with engine running as P is engaged that that stops on full engagement
    - with transfer box "in gear"
    - diagonal opposite wheels jacked causes grinding noise when turning by hand
    - engine running the grinding persists in transmission N, but with reduced intensity, only stops in P
    - transmission in D/R the grinding is louder
    - transmission in D the frequency of the grinding varies depending on transfer H/L - higher frequency in H

    This is leading me to the conclusion that the transfer chain has snapped:
    - the transfer H/L/N selection works/has an effect
    - there is drive through the main transmission
    - front and rear axles are still connected through the VC
    - there is no connection between VC and H/L/N side

    Any other suggestions/thoughts?

    Now, for the replacement if consensus is a broken chain: I can get a second-hand transfer box for $750 confirmed to have been working when removed from donor. Is it worth spending another $300 for it to receive new bearings and seal kit?
    Quick reply to this message Reply  

  13. #11
    JUNIOR ROVER
    Join Date
    August 2nd, 2007
    Location
    Southern California, USA
    Posts
    820

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    Personally, I can't imagine the Transfer case chain snapping. It's a pretty beefy chain in there, so it may loosen and give out machine gun noise, but the odds of it snapping seems very remote to me.

    To me, the symptom sounds more like a dead torque converter.
    02 P38
    SoCal, USA
    Quick reply to this message Reply  

  14. #12
    Premium Member Escape's Avatar
    Join Date
    June 4th, 2007
    Location
    Belgium
    Posts
    1,185

    Re: Transfer Box/Viscous Coupling - Grinding Noise & No Driv

    While it is indeed unlikely the transfer chain has snapped, all your tests point to the problem being at the output side of the transfer box. Making the chain the prime suspect. You'll have to take the transfer case off and open it up to see what broke. If it was the torque converer, P would still work.
    As for the test, with one wheel jacked up and transfer and/or autobox in neutral, you should be able to rotate that wheel, but with significant force and only slowly. You'll have to overcome the resistance of the viscous coupling, but it should be possible. If not, it point to the viscous being locked up, so that will need changing as well. Not hard when you have the transfer box off anyway, so well worth checking.

    Filip
    4.0 SE manual, 1997, 'Priscilla': current daily
    4.0 SE manual, 1995, 'Piper', built for offroad with tuned 4.6 on MS: lost in fire
    4.6 SE auto, 1995, 'Prue': awaiting attention
    2.5 DT manual, 1996, 'Paige': retired and stripped
    D90 TD5, 2005, 'Nessie' TR2 racer: sold
    Quick reply to this message Reply  

Quick Reply Quick Reply

Register Now

Similar Threads

  1. 2003 TD6 Grinding noise transfer box message
    By k9steve in forum Range Rover Mark III / L322
    Replies: 2
    Last Post: May 5th, 2014, 05:15 AM
  2. How To Test Viscous Coupling Transfer Case
    By Selby P38 in forum Range Rover Mark II / P38
    Replies: 19
    Last Post: March 25th, 2011, 09:04 AM
  3. Testing the viscous coupling of the transfer box
    By klex in forum Range Rover Classic
    Replies: 3
    Last Post: March 1st, 2010, 09:53 AM
  4. Changed transfer box viscous coupling today
    By greenslade in forum Range Rover Mark II / P38
    Replies: 3
    Last Post: January 31st, 2008, 12:30 PM

Tags for this Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBadvanced CMPS v4.3.0