RR G Box clonk

A

Alun P

Guest

• Sep 10, 2004

• #1

RR Classic, 91, 3.9 Auto

I bought this RR as a work horse to shift my music equipment around and it
does an admirable job. I bought it cheaply with a few known faults such as
blowing exhaust, failed electric windows etc......all of which have now been
cured.

The one factor that is of concern, which is apparent only when the vehicle
is hot and has been run for quite a while, is a 'clonk' when shifting from
drive into reverse.

There is barely a 'clink' (LOL) when cold but hot it seems a lot louder, are
we talking lubricants or something a little more major?

AlunP

 

R

Richard Savage

Guest

• Sep 10, 2004

• #2

Alun P wrote:
> RR Classic, 91, 3.9 Auto
>
> I bought this RR as a work horse to shift my music equipment around and it
> does an admirable job. I bought it cheaply with a few known faults such as
> blowing exhaust, failed electric windows etc......all of which have now been
> cured.
>
> The one factor that is of concern, which is apparent only when the vehicle
> is hot and has been run for quite a while, is a 'clonk' when shifting from
> drive into reverse.
>
> There is barely a 'clink' (LOL) when cold but hot it seems a lot louder, are
> we talking lubricants or something a little more major?
>
> AlunP
>

AIUT it's caused by wear on the splines of the o/p shaft from autobox
into the transfer box. IIRC the ultimate fate is stripped splines and
no drive! My does the same which is REALLY annoying as I had an
Ashcroft refurb autobox fitted not many years ago to my 88 RRC 3.5.

Somewhere in the NG you will find a link to a site showing the gruesome
results.

The only way I ever reduce the clunk is to come to a *complete* stop
before engaging reverse, select neutral, foot off the brake for a few
moments, then foot hard on the brake and then engage reverse. Great if
you are backing and filling into a space.

HTH

Richard
--


Reply to RJSavage at Bigfoot dot com

 

A

Austin Shackles

Guest

• Sep 10, 2004

• #3

On or around Fri, 10 Sep 2004 15:46:22 +0100, Richard Savage <[email protected]>
enlightened us thusly:

>
>
>Alun P wrote:
>> RR Classic, 91, 3.9 Auto
>>
>> I bought this RR as a work horse to shift my music equipment around and it
>> does an admirable job. I bought it cheaply with a few known faults such as
>> blowing exhaust, failed electric windows etc......all of which have now been
>> cured.
>>
>> The one factor that is of concern, which is apparent only when the vehicle
>> is hot and has been run for quite a while, is a 'clonk' when shifting from
>> drive into reverse.
>>
>> There is barely a 'clink' (LOL) when cold but hot it seems a lot louder, are
>> we talking lubricants or something a little more major?
>>
>> AlunP
>>
>
>AIUT it's caused by wear on the splines of the o/p shaft from autobox
>into the transfer box. IIRC the ultimate fate is stripped splines and
>no drive! My does the same which is REALLY annoying as I had an
>Ashcroft refurb autobox fitted not many years ago to my 88 RRC 3.5.

not normally on the auto box, ISTR. same effect on my 110 caused by worn
front CV joints, might be worth a check.

Also, he's probably got a borg-warner transfer case on that'n, in which case
it's very unlikely to be the infamous shaft wear, which mostly affects
unmodified LT230s on LT77s and early R380s, AIUI.

however, with the same box/Tbox combo in the 110 I got a really loud clang
on some occasions if shifting from forward to reverse too briskly. later
decided that most of the play was in the front axle, and sure enough, the
CVs were seriously worn. Only ever replaced one, mind, which started
rattling on full lock.

 

A

Austin Shackles

Guest

• Sep 10, 2004

• #4

On or around Fri, 10 Sep 2004 13:18:09 GMT, "Alun P"
<alun.priddle@NOSPAMblueyonderDOTcoDOTuk> enlightened us thusly:

>RR Classic, 91, 3.9 Auto
>

BTW, you identify the BW transfer box by the absence of a "DIFFLOCK"
position on the transfer lever, it only moves forward and back, not side to
side.

the BW has a viscous coupling instead.

 

A

Alun P

Guest

• Sep 11, 2004

• #5

> BTW, you identify the BW transfer box by the absence of a "DIFFLOCK"
> position on the transfer lever, it only moves forward and back, not side
to
> side.

There is only forward and back selection on the transfer high>low ration
lever, no diff lock option so must be BW. does that alter the diagnosis???

AlunP

 

A

Austin Shackles

Guest

• Sep 11, 2004

• #6

On or around Sat, 11 Sep 2004 04:58:28 GMT, "Alun P"
<alun.priddle@NOSPAMblueyonderDOTcoDOTuk> enlightened us thusly:

>> BTW, you identify the BW transfer box by the absence of a "DIFFLOCK"
>> position on the transfer lever, it only moves forward and back, not side
>to
>> side.
>
>There is only forward and back selection on the transfer high>low ration
>lever, no diff lock option so must be BW. does that alter the diagnosis???

IMHO yes - I'd be very surprised if it was gearbox output shaft problems.
The morse chain can be slack in the BW transfer box, but I'd check your
propshaft joints, CV joints and axle splines. any or all could be worn, CVs
especially if the swivels have been left dry or contaminated with water.

 

R

Richard

Guest

• Sep 11, 2004

• #7

our 95 disco does the same, clunk when hot, quiet when cold. spoke to
several people and they all say rest at neutral for a couple of secs before
going to D or R. It seems to help a bit. I dont the think spline thing
affects the auto boxes ?
Richard


"Alun P" <alun.priddle@NOSPAMblueyonderDOTcoDOTuk> wrote in message
news:[email protected]...
> RR Classic, 91, 3.9 Auto
>
> I bought this RR as a work horse to shift my music equipment around and it
> does an admirable job. I bought it cheaply with a few known faults such as
> blowing exhaust, failed electric windows etc......all of which have now
been
> cured.
>
> The one factor that is of concern, which is apparent only when the vehicle
> is hot and has been run for quite a while, is a 'clonk' when shifting from
> drive into reverse.
>
> There is barely a 'clink' (LOL) when cold but hot it seems a lot louder,
are
> we talking lubricants or something a little more major?
>
> AlunP
>

 

A

Alun P

Guest

• Sep 12, 2004

• #8

that would start to make sense actually, as on the odd ocassion, there is a
stiffness on the steering when turning to the right, it seems the steering
locks and the power steering 'fails', only to the right though, not left.
turning back to the left and then to the right again clears the problem.this
again could point tp front swivel joints or CV????

AlunP