Diff servicing.

[Corin Denton]

I'm posting this on the General TVR site as some of the Griffters might be able to help.

On my 1998 500, when setting off from cold I get a light whine from the rear diff which reduces after a short time, when it gets warm I suppose? The car has always been serviced at the correct intervals by TVR with the bills to support therefore I would imagine that the diff oil has been changed at prescribed intervals.
The car has covered 50K, any suggestions welcome?

Thanks

Corin

[Seasider]

Hi Mate, when was the last service? & before doing anything i would change the oil (80/140 for a BTR, it might have been forgotten once or twice....

[gideonr]

My Chimaera also has a slight whine from the differential. According to Christopher Neil's whining diffs are not uncommon, but they rarely go wrong completely.
The diff can be reconditioned for £400-£500, but if it doesn't get any worse then it's ok to leave it alone.

[Corin Denton]

Hi Derek!

I had it serviced by Peninsula in October but it wasn't scheduled for a diff service - I'll try that and go from there!

Thanks!

[Seasider]

Doesn't take long...

Possibly leave to drain over night or whilst doing something else. Offside wheel off & a long tube to fill from outside the arch (heat the oil first as it's as thick as thick stuff)

>> Edited by Seasider on Wednesday 5th January 09:23

[Corin Denton]

Beauty!

Did you use Mobil oil?

[Seasider]

Couldn't get any unless it was 25ltr!!! so i used Millers it's the same spec...

[Painey]

I'm a touch concerned about the diff on my griff. Noticed a couple of drops of oil on the garage floor where the rear of the car normally sits so should I be concerned? Also, this 'whining' noise that people mention, I've noticed that sometimes when pulling through the rev's (normally in 1st/2nd before road noise drowns it out) you can hear what sounds like an electrical whirring noise as you accelerate? It's not a constant noise/whatever but increases in pitch as the revs go up.

The car had it's full 36k service last May so I'd have thought it should be ok? Or am I just paranoid as ususal?

Cheers - Chris

[GreenV8S]

Painey said:

Or am I just paranoid as ususal?

Diagnosing noises is always going to be tricky, but from your description it sounds to me like a badly worn crown wheel/pinion. The good news is that in my experience it gets loud enough to leave you in absolutely no doubt at all that there is a problem, before it finally lets go.

[chimburt]

Hey Corin,
got mine done at about 60-65k. left it for quite a while, and eventually the induced drag becomes quite noticeable when you lift off, to the point where once i'd had it done i had to use te brakes to slow the car for a speed camera i was going past regularly.
don't worry too much until it gets really noisy.

[Painey]

a badly worn crown wheel/pinion

What's that then as I have absolutely no idea whatsoever? More importantly is it going to be expensive! Should I remortage the house now!!

Cheers



>> Edited by Painey on Wednesday 5th January 14:44

[Guillotine]

low mileage/second hand...£200.

mines had a slight whine for 30,000 miles, road and track!

still the same.

[sharkie]

Oil spots on the floor may just be from the breather, when the diff gets hot it breaths a small amount of oil mist, this condenses and runs down the right-hand side of the rear cover. in about 1995 there was revised rear cover introduced that had a better baffle under the breather.

If the cause is a leaking oil seal then these can be replaced without too much trouble.

One of the biggest causes of LSD chatter, leaking oil seals, gear wear and bearing noise is the use of non-approved oil.

The only oils signed-off by DANA Australia (BTR) for High performance cars are: -
Mobil SHC80W-140 ID
Castrol SAF-XJ or SAF-XA
Morris Lubricants Lodexol XFS ( great for DIY as comes in 1 & 5 Litre bottles)www.morrislubricants.co.uk

Many other oils use different friction modifiers that are not compatible with the High temp' seals used

Parts and Service for the Dana (BTR) diff:-

TAL Limited Bromsgrove [phone] (These Guys took on DOME's Main workshop, Lots of Genuine parts ex Stock)

JP Raceshop Silverstone [phone]