noisy lsd and changing the oil.

[JeffC]

my car is pretty much new with next to no miles on , the diff doesnt whine but sounds nasty when at cruising speed on and off the throttle sounds like the cogs are bashing off each other , I have been following this thread with interest on blatchat but am not a member as yet so cannot post on the thread, http://www.blatchat.com/t.asp?id=216448&pn=1&a... after reading it I thought at £10 to change the oil it has to be worth a go so I have bought some of the Ford 90 grade oil part no. 1 197 783 as recommended,now I know my car was supplied with an Lsd so am i right in thinking that I would need to add some friction modifier when i change the oil ? and if so would something like this do the job ?


http://www.ebay.co.uk/itm/300691625100?ssPageName=...

or

http://www.ebay.co.uk/itm/251044061723?ssPageName=...

[DCL]

I've just bought some of this oil and, as I've tried everything else to quieten the diff, it's worth a go.

Whether you need a friction modifier or not depends on which diff you've got. The quaife ATB diff strictly speaking doesn't need one (although Caterham did use the Lubegard product at one time I believe to help with noise).

http://www.caterhamparts.co.uk/product.php?id_prod...

Plate type diffs may need a friction modifier - best to refer to the manufactures recommendations.

Edited by DCL on Tuesday 15th May 21:42

[JeffC]

thanks , I never thought about caterham for the lube, will give cc parts a shout tmrw, not sure what diff mine has fitted, but even if it doesn't need the additive I dont suppose it will harm it ?

[PINGUY]

If it's a FORD Diff check on the bottom side of the diff casings : If you find "ATB" stamped on it then it's a Quaife ATB and you do not need friction modifier.
If your diff is a BMW, then you for sure have a real LSD and you need friction modifier.
(BMW diffs at CC only exist OPEN or with LSD's, but not with ATB's (for the moment !))

[JeffC]

cheers will check, I know its a ford sierra 3.9 L.S.D supplied by road and race 2 years ago.

[sam919]

Its probably a titan if r and r fitted it! but maybe not. If its been run in then a reccomended GL5 is the one you want to use and 1 litre of the stuff. I used some Smith and Allen, for breaking in the Elite friction plate diff i got this season, then drained it and put in another litre, but its a little noisy on the over run:

http://www.ebay.co.uk/itm/Smith-Allan-EP-80w-90-Ge...

It was interesting reading on the BC site, i have just got a litre of fuchs titan to try this wknd, as said 1 litre doenst break the bank balance...:

http://www.opieoils.co.uk/p-68901-fuchs-titan-race...

The Smith and Allen heated up quite a bit after 10 laps of abuse and became quite thin, ill try the fuchs and see what happens.

Might be worth giving R and R and tinkle they are freindly chaps and dont hold back with info.

[JeffC]

after reading the thread a bit of what i read made sense, when I had my Csr diff rebuilt after i sheered the mounts on the casing I just bought some standard ep90 oil from the local motor factors (comma from memory?) and it was very noisy, so bad I actually removed it and sent it back for Phil and asked him to recheck it over, he did and said it was fine so i refitted it, I used the same grade oil back again and it was as bad, certainly noisier than before it was rebuilt, I wonder now if it was the oil I used , which if it makes so much difference adds up!

the diff in my car isn't as bad as the Csr but no where near as quiet as standard Sierra Lsd s that I have had fitted in Westfields over the years, they were always silent, but im also presuming they wouldn't have worked as well ?? anyway the local Ford dealer has the ford oil the guy on BC recommends so will give that a whirl with some additive in and see what its like.

[2slo]

The BMW lsd in my 2011 R400 was replaced by CC due to excess noise etc and the replacement isn't too bad all things considered. I'm not far from you if you want to have a look at mine at some point to compare.

[sam919]

JeffC said:

after reading the thread a bit of what i read made sense, when I had my Csr diff rebuilt after i sheered the mounts on the casing

Another case failure! we went through two one weekend, ended up bracing the top mount holes with a metal strip to the lower holes each side, and making two rose jointed braces that went from two casing bolts to the chassis either side of the diff......pain getting the thing out in the first place.

I have another 3.92-1 CWP if you fancy chainging it/ think its worn, the wear should be even over the length of the CW teeth i.e. not one end or the other

[JeffC]

2slo said:

The BMW lsd in my 2011 R400 was replaced by CC due to excess noise etc and the replacement isn't too bad all things considered. I'm not far from you if you want to have a look at mine at some point to compare.

cheers would be interested in a look at some point, is the Bmw diff as quiet as it is supposed to be ? did you upgrade from ford diff or was it supplied with bmw unit from new ?


Sam my diff is as new and as said not really that loud so not looking to replace it just to see if I can make it more road friendly, if I did change it I think I would be tempted with something like a 3.6 or 3.3 as its revvy with a 3.9 on the road at cruising speed.saying that Im at Cadwell Park on Monday and have just booked knockhill, blyton and Croft so the 3.9 will prob work well on track.

[2slo]

JeffC said:

is the Bmw diff as quiet as it is supposed to be ? did you upgrade from ford diff or was it supplied with bmw unit from new ?

CC told me that my car had one of the 1st of the BMW LSDs (they built it for me). From new it had a really loud whine (I didn't want to drive it even short distances without ear protection)and it knocked badly when any lock was applied. They agreed it needed changing and so they put another BMW LSD in. Huge improvement, quieter (not silent, but I wasn't expecting it it be) and it doesn't knock any more. It still has driveline shunt when changing gear meaning it's difficult to drive smoothly but, overall, a big improvement on the original. From my car and from driving another R400 with the BMW diff (which was as noisy as my original)it seems to be a bit of a lottery whether you get a noisy diff or a slightly less noisy one. I guess it will bother some people and not others.
I will say that CC were fine about it when I spoke to them and explained. They had the car in and changed the diff under warranty straight away so no complaints there.

[sam919]

JeffC said:

I think I would be tempted with something like a 3.6 or 3.3 as its revvy with a 3.9 on the road at cruising speed.saying that Im at Cadwell Park on Monday and have just booked knockhill, blyton and Croft so the 3.9 will prob work well on track.

I have a 3.6-1 as well!

[JeffC]

just a shame they are a mare of a job to change! I thought I was going to have to take a grinder to my Csr first time I took it out!

got 1 liter of oil from Ford today £7.40 and ordered the additive from CC this afternoon so should have it done on Friday see if its any better!?