What diff do i have?

[Jcerb]

Is there a way of telling if i have a standard plate type diff or the Hydratrak? When the wheels are raised and spin one it works like a normal diff turning opposite ways. I cannot push both wheels same direction if that gives any clues. Be interesting any views!

[gruffalo]

Joe,

I don't think they used a plate LSD in the Cerb, it was either an open diff or a Hydratrack.

I take it the car was not in gear when you were trying to turn the wheels otherwise you would have had to turn the engine as well.

[BCA]

gruffalo said:

Joe,

I don't think they used a plate LSD in the Cerb, it was either an open diff or a Hydratrack.

I take it the car was not in gear when you were trying to turn the wheels otherwise you would have had to turn the engine as well.

Open diff

It'll either be a friction type or Hydratrak from the factory. No idea how to tell the two apart, but I could tell it by driving it, hydratrak has a strange and inconsistent feel, one that I never got on well with, I much prefer the lesser 4.2's standard issue friction diff. No Cerbera has ever been made with an open diff, having experienced a Cerbera with an open diff (Hydratrak gave up at 70k miles) - I assure you it's awful.

[.Mark]

BCA said:

hydratrak has a strange and inconsistent feel

Could you elaborate on that? I've got a 1999 4.5 and was wondering what diff I have too.

[pmessling]

this is the one from my 2004 4.5





which is the hydratrak lsd, same diff that i had in my ZT V8 when i had it.

[ridds]

Hydratraks have a large metal tag on the side of the diff under the large fill/level plug.

Pretty sure my Hydratrak turns both wheels forward when you turn one wheel.

Daft question, is it out of gear.;)

[high52kojak]

Hydratrak has small grooves machined around the output wheels, just below the toothed part.

[Jcerb]

Hi Martin,

The car was in gear and i had a mate on one wheel and i was on the other, and we could not turn the wheels the same way, the reason i ask is that i had a plate type LSD diff on a polo G40 a while back and it would turn both wheels same direction in the same situation, pre load and ramp angles i guess would have an affect. BCA i couldn't say as i have never driven another cerbera, it's not snatchy like the polo, but it's a totally different kettle of fish being FWD compared to RWD. MARK maybe this helps? St8six are doing the diff bushes soon they will know i'm sure, just interested to know. Thanks for your input guys.

[Fudgenudger]

What does Hydratrack actualy mean and how much different is it to an LSD ?

[Wocka]

Fudgenudger said:

What does Hydratrack actualy mean and how much different is it to an LSD ?

My understanding is the Hydratrak is a viscus LSD where as the other is a clutch/plate LSD

[ridds]

Jcerb said:

Hi Martin,

The car was in gear and i had a mate on one wheel and i was on the other, and we could not turn the wheels the same way, the reason i ask is that i had a plate type LSD diff on a polo G40 a while back and it would turn both wheels same direction in the same situation, pre load and ramp angles i guess would have an affect. BCA i couldn't say as i have never driven another cerbera, it's not snatchy like the polo, but it's a totally different kettle of fish being FWD compared to RWD. MARK maybe this helps? St8six are doing the diff bushes soon they will know i'm sure, just interested to know. Thanks for your input guys.

Car in gear, turning both wheels the same way.... You do realise you're trying to turn the engine over with it in gear don't you. That will be a little harder on a V8 Cerb (particularly a 4.2 with aggressive cam profiles and I suspect higher comp ratio) than on a S/C Polo..

[Omerta]

I asked this question some years back and there was some good info from trackcar / jools and others. Do a search...

[Jcerb]

It was in gear, i'm sure the compression is much greater was just trying the same as what we had on the polo a while back, though now becoming blurry as to what we did Will learn more in time, sure Str8six will tell me as they are taking it out to re seal and do the bushes. Appreciate the time from you guys, plus that diff painting looks great!