Question about VYSS stock diff (manual 6 spd)

[GreennySS]

hi y'all....i wanted to change diff oil and i am not sure of which type and brand of oil
and i notice that there is knocking noise it's like coming from the diff.....it was when the car is hoist up and i turn the drive-train...either ways...and there is like metal knocking noise....

please help....before it gets worst..


THX y'all

[soop]

Yep, change the bush in the dif craddle.
As for diff oil, Castrol LSX90 IIRC .

[GreennySS]

thx alot boss...i will have a look into it and change it....

[Sean880]

hi y'all....i wanted to change diff oil and i am not sure of which type and brand of oil
and i notice that there is knocking noise it's like coming from the diff.....it was when the car is hoist up and i turn the drive-train...either ways...and there is like metal knocking noise....

please help....before it gets worst..


THX y'all

AS for DIFF OILS, your VYSS V8 has an LSD fitted and it now seems that only fully synthetic 80-140 diff oils are now recommended for these diffs.

Both Castrol and Penrite make a synthetic diff oil specifically suited to these LSDs and they are both 80w-140 grade fully synthetic diff oils. I went into this with both companies earlier in 2010 and the following was the response from their technical departments in relation to diff oils for the VY Limited Slip Diffs:

1. CASTROL
VY LSDs

"The manufacturers specification is ONLY to use a full synthetic product. We always
recommend the SAF-XA in the lsd's of these models. It is full synthetic
and not a problem with seals, it is the product that is equivalent to
GM's specification. Do not add any additives to it, even if stated in
the vehicle handbook, its not necessary these days.
Regards,
Castrol Lubricants Technical Services."

http://www.tds.castrol.com.au/pdf%5C...a_b1769_04.pdf

AND

2. PENRITE

VY LSDs.

"From the information you have provided, our recommendation is SIN Gear Oil 80, synthetic SAE 80W-140, which will be the best product for your LSD.

This product contains the friction modifier – so please do not add any additional additives to this product as it may attack the seals.
Please find attached the information sheet on this product for your perusal.
Regards,
Technical Officer
Penrite Oil Company"

SIN GEAR OIL 80 - Penrite Oil

Both Castrol and Penrite declined to recommend any of their mineral based diff oils for the VY LSDs when I asked them about it.

AS indicated, with both of these products you do not purchase and add the Limited Slip Diff additive even though the metal tag attached to the VY diff states "use approved lubricant and friction modifier".

Sorry - cannot help with the cause of the clunking noise in your diff but it sounds expensive.

[soop]

The clunking is a $40 bush!

[ARATIC]

Clunking could be a lot of things, not necessarily the rear cradle bush.

+1 on Castrol SAF-XA, or as Sean says the Penrite SIN. I prefered to use Castrol as the bottles have a funnel tube so can be 'squeezed' straight into the diff

[sp001in]

sounds like backlash on the crown and pinion. Can you replicate it on the road, by letting off the throttle at 60kph wait for the revs to fall below 1500, then tap the accelerator?

If so, go see a diff shop. I had that problem, replaced the diff all fixed.