[urq] Diff Locks

[Bill Bennett]

the entire drive train is loaded, mounts at the stops, vibration city even 
at a stop, if you picked up the rear tires, the vibration would go away.
 Bill
----- Original Message ----- 
From: "Brandon Rogers" <brogers at terrix.com>
To: <Louis_Alain_Richard at computerhorizons.com>
Cc: "Urq List" <urq at audifans.com>
Sent: Monday, June 06, 2005 11:47 AM
Subject: Re: [urq] Diff Locks


yeah but it vibrates (rough idle) when the car is stationary.  I don't see 
how those factors can cause vibration when  the car ain't moving.

Brandon
  ----- Original Message ----- 
  From: Louis_Alain_Richard at computerhorizons.com
  To: Brandon Rogers
  Cc: Urq List
  Sent: Monday, June 06, 2005 12:18 PM
  Subject: Re: [urq] Diff Locks


  I don't think so.

  I have the same behaviour on my car. My conclusion is "drivetrain stress" 
or windup.

  As each wheel as a different diameter (pressure, wear, weight on each 
axle, etc) then one axle as a greater developpment than the other. When 
rolling, this difference is absorbed in the slippage of each tire.

  When you coast to a stop on an adherent surface with the center diff 
locked, it means that one axle has a rotational load and this put a stress 
on the engine/transmission/diff mounts. This is the vibration you feel in 
the body.

  As a proof of this, if you can't have the center diff to disengage (when 
the car is stopped), it means there is a load on the dog clutch, CQFD.

  To play with my theory, deflate your font tires to 25 psi and inflate the 
rears to 35 psi. Lock the diffs, roll 100 ft straight ahead and notice the 
vibration. Then do the opposite (35 front, 25 rear). You'll see that the 
vibration is a lot less present.

  Louis-Alain



  -----urq-bounces at audifans.com wrote: -----


    To: "Urq List" <urq at audifans.com>
    From: "Brandon Rogers" <brogers at terrix.com>
    Sent by: urq-bounces at audifans.com
    Date: 6/6/2005 12:17
    Subject: [urq] Diff Locks

    GUys-
    did some highway driving in our downpour over the weekend so I locked 
the center diff - when I came to a stop I realized I had forgotten to unlock 
the diffs - I could tell the diffs were still locked (other than the fact 
the green light was still on) because the motor was idling a little rough. 
Turned the dial to unlocked and of course the roughness went away.

    Does this mean I have a vacuum leak somewhere in the lock system?

    TIA

    Brandon
  =
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