Diff Trouble
Diff Trouble
Author
Discussion

Mad Mark

Original Poster:

2,345 posts

262 months

Sunday 26th July 2009
quotequote all
How reliable is the Cerb diff
and
what are the symptoms of it going wrong?

Del 203

12,728 posts

279 months

Monday 27th July 2009
quotequote all
frown

Number 1 not 11's wink & loud noises


+ a bump for you smile

Brummmie

5,284 posts

251 months

Monday 27th July 2009
quotequote all
I have the 4.2 diff in mine, albeit with a higher gearing, and it has taken some serious stick! Cant speak for the 4.5 hydratrack one though.

Mad Mark

Original Poster:

2,345 posts

262 months

Monday 27th July 2009
quotequote all
I'm getting some strange behaviour from the rear of the car!!
In extreme cases I notice I am having to steer to the right slightly to go in a straight line and then get a heavy 'jolt' from the rear and the car straightens up. In lesser cases I just get the 'jolt'.

I have checked the chassis out and have found a slight crack near where the roll bar connects to the chassis and am having this welded later in the week but don't think this is related.
I have changed the top diff bush as the old one was knackered so also know the bracket is good too.

morebeanz

3,283 posts

266 months

Monday 27th July 2009
quotequote all
I've had two go on mine, so I would suggest that the hydratrack is not that robust. Symptoms were very like a slipping clutch, and eventually I lost all drive when it let go.

If it goes again, I will definitely look for an alternative!

Mad Mark

Original Poster:

2,345 posts

262 months

Tuesday 28th July 2009
quotequote all
Mine feels as tho it is going the other way and tightening up!!
Assuming that it is my diff that is playing up! I have still not ruled out things like broken shocks / chassis or bushes.

Mad Mark

Original Poster:

2,345 posts

262 months

Thursday 30th July 2009
quotequote all
Apparently there is and article in this months PPC about diffs.

What type of diff is in the Cerb is it a viscous, touque biasing or a clutch pack type.
I know its supposed to be a hydratrack but is that one of the above styles?

stuthemong

2,533 posts

247 months

Thursday 30th July 2009
quotequote all
Could your symptoms be described by a sticking brake calliper? Next time it does it, pull over, and feel for heat on both rear disks. If one is noticably hotter than the other you may have it diag'd!

MackemPete

965 posts

248 months

Thursday 30th July 2009
quotequote all
I had some issues with mine a while back. Came round a sweeping corner in a very exuberant manner (completely sideways biggrin ) then the car developed a very loud clunk from the diff everytime I went round right hand bends. It was that bad it felt like the diff was welded. Took the car straight to the dealer, where it miraculously fixed itself. Its never returned despite repeated exuberance smile

jammy_basturd

29,778 posts

242 months

Thursday 30th July 2009
quotequote all
Has anyone thought about swapping to a Quaife ATB? With all these stories of diff problems, and the back end snapping out (whether it be driver fail or diesel on road) I'm wondering whether a more 'sympathetic' diff might be a good idea? Least Quaife have a bullet proof reputation.

itiejim

1,822 posts

235 months

Thursday 30th July 2009
quotequote all
BCA has a Quaife after the hydratrak failed.

Personally, my (1996) car still has the original clutch pack type LSD in which I'm very happy with. I think that it is the most "sympathetic" type of diff available as they tend to lock up slower than the geared (Quaife) type and cause less drivetrain shunt.

Mad Mark

Original Poster:

2,345 posts

262 months

Wednesday 5th August 2009
quotequote all
Any body got any ideas how much a replacement diff would cost?
either recon or breakers!!

HRG.

72,863 posts

269 months

shpub

8,507 posts

302 months

Thursday 6th August 2009
quotequote all
HRG. said:
Gearboxman (CTS) will rebuild a BTR diff for around 320-350 + VAT.

I think that is more sensible than getting a s/h unit that you don't know anything about.

dirty boy

14,860 posts

239 months

Thursday 6th August 2009
quotequote all
Was it Gattor who had a Quaife diff too? Scole Engineering fitted it for him IIRC.

Mad Mark

Original Poster:

2,345 posts

262 months

Thursday 6th August 2009
quotequote all
So is a BTR diff also a hydratrak or are they different?
And are we talking viscous or clutch pack / Salisbury diffs?
(I'm guessing viscous!)

I'm sooo confused wobble lol

TT Tim

4,168 posts

277 months

Thursday 6th August 2009
quotequote all
I think a few of the T350 guys have changed to Quaife diffs, I know that Paul Edwards (Tailslide) has, seems a good, if expensive, option.

Mark if you get stuck, I have a good diff' you can borrow until you sort yours. I'm not selling it as it's my spare, but as I'm only doing 2 or 3 sprints this year I'm hoping I'll not be needing it in the near future. biggrin

Tim

shpub

8,507 posts

302 months

Thursday 6th August 2009
quotequote all
Cerbs had two types of diff: standard and hydratrak. Both are BTR just different internals.

itiejim

1,822 posts

235 months

Thursday 6th August 2009
quotequote all
And by standard you mean clutch pack

VPower

3,598 posts

224 months

Thursday 6th August 2009
quotequote all
4.5's have the Hydratak diff as standard, which is a viscous unit.

Jack up one rear wheel and try to turn it.
If it is hard to turn, the viscous unit is OK.
If it spins easy, then it may have been damaged by too much abuse (it needs to cool down!)

Anybody got any photo's of the Hydratrak in bits?
I suspect it is the same viscious unit as fitted to the Rang Rover center diff, a Borg Warner silicon sealed unit.

Steve