Diff Additive - Molyslip / Activ8?

[debaron]

Hi all,


My diff is whining quite considerably of late. It was rebuilt about 10 K ago and was briefly quiet. It went back to the garage and they looked at it again. Zero play in it - as the rest of the drivetrain (UJ, Prop etc) so I've accepted that it's just a noisy one!

I'd like to put some additive in there to quieten it down. What's the official and unofficial line on additives like molyslip and activ8?

Does anybody use them and what is the pro's/cons?

One thread suggested that it may hinder the "limited slip' ability of the diff and revert it to a "normal" one in terms of operation.

Cheers

Ryan

[EggsBenedict]

i wouldn't put anything like that in it. According to mr heath, the diff oil should be changed frequently - officially every 12K miles. The stuff you need to put in is fairly expensive. Perhaps a change of diff oil would help? I'm using the Motul stuff, which seems v expensive, but i've been told these diffs are eye wateringly dear.

[haircutmike]

And a pain to change the oil, probably why a lot whine!

[Simon says]

haircutmike said:

And a pain to change the oil, probably why a lot whine!

How true

[rigga]

This has been reccomended in the past for cars with lsd's

http://www.amsoil.com/storefront/ada.aspx

[debaron]

rigga said:

This has been reccomended in the past for cars with lsd's

http://www.amsoil.com/storefront/ada.aspx

Excellent - Have ordered some from here: http://www.performanceoilsltd.co.uk/amsoil_additiv...

Will stick it in and post back with the results!

Cheers

Ryan

[bobfather]

Be very careful, as said above, only use the recommended oil. I speak from personal and expensive experience. The LSD in these diffs are very sensitive to oil viscosity. I completely wrecked mine; I ended up replacing the unit.

[Pink_Floyd]

bobfather said:

Be very careful, as said above, only use the recommended oil. I speak from personal and expensive experience. The LSD in these diffs are very sensitive to oil viscosity. I completely wrecked mine; I ended up replacing the unit.

How was it wrecked, was it locked solid or did it not lock at all like a normal diff ?

[bobfather]

Pink_Floyd said:

bobfather said:

Be very careful, as said above, only use the recommended oil. I speak from personal and expensive experience. The LSD in these diffs are very sensitive to oil viscosity. I completely wrecked mine; I ended up replacing the unit.

How was it wrecked, was it locked solid or did it not lock at all like a normal diff ?

The LSD locked so the car could only travel straight forwards or backwards. When turning the least weighted wheel hopped to maintain equal rotation.

[darkcat]

I had the wrong oil in mine - it locked.
BUT it freed itself once i put the correct stuff in and gently turned one wheel...

Ive just ordered some Millers CRX LS 75w140 - should do the job nicely.

[carsy]

Just put castrol lsd 75 140 in my newly built GKN. Not tried it yet, hope its ok.

[Simon says]

carsy said:

Just put castrol lsd 75 140 in my newly built GKN. Not tried it yet, hope its ok.

Been in mine for over 2 years with no problems previous to this I used Millers same weight both work just fine,my diff as never been silent but it as got no worse in 5 years I just put it down to build quality/sloppy tolerances by who ever built it in saying that the Castrol seemed a slight improvement over the Millers as I was getting the occasional moan from the LSD plates on low speed turns when hot this as disappeared with the Castrol

Edited by Simon says on Thursday 12th May 10:24