Diff upgrade question

[AM04ARO]

I have upgraded to the 3.9 diff. First one broke. Second one whines, am told I need to run it in for 1000 miles and let the anti friction oil do its stuff. Personally I am not so sure.

Anyone else had a new diff and had to run it in etc?

Am happy with the garage thats done the work but not convinced a mechanical product should make a noise fitted new or refurbished.

Views Please

[delmeekc]

Mine had the wrong oil in it (cars done 80k), greens in cooperation with Wortec (think thats how you spell it) changed the oil, mix of redline and modifier and now it's quite noisy but now works a treat. Where as before is didn't work at all, just span one wheel. It's not really noisy but i could hear it today doing 85 and 140mph (on a private track of course) but aint going to worry about it.

What oil is in it? the original stuff that somebody put in mine was ready mixed with the modifier and it was too concentrated and slipped to much.

[Le Sarthe]

Have to say had not prob at all with mine brilliant - get the odd clunk when manouvering at very low speed but very rarely.

When researching this (was first with Wortec I think) in Oz soem guys seem to get whines and noises and it is either solved by modifying the oil mix or replacing soem of the gears.

My run in period lasted about 50 miles

I still reckon this is one of the best mods for assisting in real world driving gains.

[AM04ARO]

Thanks for the responses.

Clunkin has been fixed, just whines, normally on acceleration only. If I am not the only one (and does not sound like it) I will put up with it until it goes........

[demolition man]

How much is an uprated diff for a 05 VXR?

Sounds a good mod to do. How much extra acceleration do you get?

[BO55 VXR]

demolition man said:

How much is an uprated diff for a 05 VXR?

Sounds a good mod to do. How much extra acceleration do you get?

A couple of nuggets short of £1500.

A remember someone saying that it has a perceived feeling of an additional 50BHP

[ringram]

Yes acceleration is improved depending on if you can get all the traction down to the ground.
Drag radials would help here. You might need to fit an extra gear shift in down the 1/4 mile (you will need to shift faster and more often)
It also makes 6th more useable in general.

[stevieturbo]

If the factory diff doesnt whine, then no reason why this one should.

[AM04ARO]

stevieturbo said:

If the factory diff doesnt whine, then no reason why this one should.

My thoughts exactly but it would appear that it does. Very noisy today on start up but *fingers crossed* the noise did die down a bit and the whining became intermittant.

The acceleration is a vast improvement on the old standard diff but a car that whines makes me nervous I am going to see the AA man, not being a mechanic myself.

[stevieturbo]

Even my diff doesnt whine, and I built it !!!!!

Well...2nd time around lol...first one did and it went a different route *ouch*

It did last over 1000 miles or so though. It wasnt half loud by time I stopped driving it !! Oil etc was burnt to a crisp !!!

Wont make that mistake again.

[AM04ARO]

I think my car is falling apart - the black must be a bad luck omen or something....

The large secondary noise has been traced to the powersteering and a loss of oil - no idea how or where but once I find out will let you know.

The diff is getting the Royal treatment to get it fixed. I am in a black Monaro now (and its not the fastest colour) while the forums experts get things sorted. So, its not great that I have had problems but at least the after sales service to get it resolved seems top notch, will find out Friday when I get it back.

Anyway I think my luck with the Monaro has finally started to change, managed to fill up the tank(from empty on 40 miles to go) with £39 at 85.9p a litre.........petrol pump was giving extras

[stigcv8]

where did you fill up, I'll take mine there tomorrow!

With the dif altering the gearing, can this have any effect on whp figures on dynos? If so can this account for the slight difference between the 04 and 05 cv8s or were there really engine remaps?

[monkfish1]

05 CV8 is slightly more powerful from the factory. Some changes main one being fly by wire throttle. Diff ratios are the same on both models.

[stigcv8]

so is the throttle a cable one on the 04? Simple ? I know!

[Well_Fans]

04 model is normally a cable yes - makes it easier and cheaper to stick a larger throttle body on to squeeze a bit more out the engine.

[AM04ARO]

Its finally back after weeks away. Now is probably the time to slag off the people involved for keeping it away from me for so long.

Strangely, while unhappy to be parted for so long, I am happy that the time spent was to make sure its fixed for good and the actual problem was found rather than me being fobbed off.

So, thanks to, Andy @ Picadors for keeping me mobile & Paul @ Wortec & Roger @ Monkfish for getting to the root cause.

I really had to smile when Dave the driver dropped it off and got into the standard Monaro and then said to be "Have you got a different gear box?" - the power of the ripshifter

[tiler]

AM04ARO said:

Its finally back after weeks away. Now is probably the time to slag off the people involved for keeping it away from me for so long.

Strangely, while unhappy to be parted for so long, I am happy that the time spent was to make sure its fixed for good and the actual problem was found rather than me being fobbed off.

So, thanks to, Andy @ Picadors for keeping me mobile & Paul @ Wortec & Roger @ Monkfish for getting to the root cause.

I really had to smile when Dave the driver dropped it off and got into the standard Monaro and then said to be "Have you got a different gear box?" - the power of the ripshifter

LIKE I SAID ON SUNDAY ENJOY/////////////