GKN Diff vertical movement

[carbon14]

Hi,
My Griff has a LT77 gearbox coupled to a GKN diff.
When "clutching in", or also when low rpm low gear, the diff lifts up by about half an inch and makes a deep clonk when at his highest position.
The clonk is not metallic, but rather of some kind of semi-hard plastic noise.
The clonk is a bit annoying (compared to the V8 noise) and it also gives a bit of an unwanted "rocking" to the cars' users. Obviously when applying a lot of care - and superior clutching skills - it is doable to avoid most of these ...
Is there a remedy to this, or is this standard ?
My first guess would be that the diff is held to the chassis by some mounts which have some elastic parts which are used and would need replacement... Another question is then how to access ?
Thanks in advance,
C14

[roysum]

Plenty of discussion about diff bushes on here just do a search. The top rear bush is a right PITA of a job.

It's in there somewhere !!

[Belchy]

Hi,
What you'll be needing to do is go to youtube!

search under channels, for "big5oo" (Quinnys channel!)and watch chapter 9.
Where he covers not only diff removal but also a clunking noise resulting from a loose rear bolt!!

will try a link!

http://www.youtube.com/user/big500#p/u/16/G_ucaOjb...

Hope it works!!

Hope this helps,

Belchy.

[spend]

Belchy said:

...Where he covers not only diff removal but also a clunking noise resulting from a loose rear bolt!!...

Lot of bloomin effort for a noisy knee-cap...


...bloody good cover up though

Top of diagnostic tool list should be an old grannies ear trumpet you deaf old bugger

[haircutmike]

Have a look at this thread if it is loose diff bolts!

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

HCM.

[hiltonig]

ok whats the torque settings for the diff capheads ?, Mike you state "Do them up with "thread lock" and to 48 ft/lbs " but when I checked on the list of torque settings its 36ftlbs so which is right ??

Says 36ftlbs
http://www.parkersteve.dsl.pipex.com/images/torque...

Edited by hiltonig on Sunday 9th May 17:30

[spend]

The rear cover bolts aren't so tight IIRC, the ones that hold the top bush bracket to the cover are tighter. Be careful you are talking about the right locations IMHO.

[hiltonig]

I was talking about the four capheads holding the bracket onto the diff.

[carbon14]

Thanks, that's very helpful.
So I guess the main bush needs replacement... hmm a nice winter project :-)
Meanwhile I also heard of the following "workaround" method : do not change the bush but implant an additional frame (custom maid) that would stabilize the whole. Obviously the idea is to save working hours and avoid some pain... Anybody heard of this / tried this workaround ?
Cheers,
C14

[haircutmike]

hiltonig said:

ok whats the torque settings for the diff capheads ?, Mike you state "Do them up with "thread lock" and to 48 ft/lbs " but when I checked on the list of torque settings its 36ftlbs so which is right ??

Says 36ftlbs
http://www.parkersteve.dsl.pipex.com/images/torque...

Edited by hiltonig on Sunday 9th May 17:30

In my TVR service manual, it states 48 ft/lbs for diff bush bolts.

I see what you mean as the ones we are talking about are the diff carrier bracket to diff!

Well at 48 + locktite it should never come undone .

HCM.