Sticky ? Torson LSD

[MX51ROD]

MK2.5 Sport 2002

From cold the car feel like the back axle is solid with no dif . once warmed up all is normal . Problem ?

[Oldandslow]

What does it do that makes it seem like there's no diff? If it was seized I'd expect chirping tyres and little skips as you turn tight corners.

First thing I'd try is a diff oil change, just in case. If the old oil is manky and full of bits then worry.

[MX51ROD]

Yup front wheels skip on full lock when car stone cold , once warmed up all is normal

[Buff Mchugelarge]

If the diff is seized it will only affect the rear wheels?
The inside rear wheel will skip as it turns too many times for the distance traveled.

As mentioned an oil change would be the first port of call, and a good look over for leaks / cracks or damage.

[MX-5 Lazza]

Check for seized brake callipers

[sbird]

It could also be your tyres. Some brands/patterns need some heat in them to grip. With low levels of grip you'll be likely to have the diff lock-up.

[Richyvrlimited]

The type of differential you have (Tokich-Fuji Torsen) is more like a clutch diff than an actual Torsen.

I suppose if there were no oil in the diff it'd work a bit too well then as it warms up you cause the clutch plates to slip.

[MX-5 Lazza]

MX51ROD said:

Yup front wheels skip on full lock when car stone cold , once warmed up all is normal

Oh, hang on, are you talking about a clunking from the front on full lock? Is it worse in reverse?

If so, that's a different thing altogether and is a "normal" thing, normal in that lots of MX5s do the same thing. I believe it's something to do with the power steering. It usually manifests itself on worn tyres and gets worse as they tyres wear down. A good alignment usually relieves it and new tyres usually eliminates it.

[furtive]

Yup, my 2.5 sport does the same thing when I reverse it off the drive at full lock in the morning. Release the lock slightly and it stops doing it

[Rum Runner]

Sounds more like brake pads sticking on rusty discs overnight, also any slight play in the hub will force the pad to pick up more when on full lock, espcially if the pad is sticking in the caliper as well. With the amount of salt dust on the roads at present the discs can quite easly get surface rust overnight if damp, and certainly sticking pad / caliper.
As said diff issue will be inside rear hopping...can easly been seen on loose surface.
My Shogun has centre diff lock and rear diff lock .....than can really hop on a loose surface.

[MX51ROD]

Thanks for input chaps , pretty sure the diff is where the problem lies , this only happens first time I , move the car off drive when it is cold,any full lock turns once the drive train is warm are normal , as I drive forward the front wheels appear to skip ( used to have a go cart with solid axle and that behaved the same at low speed ) , off to Freelance Mazda shortly , so will get the guys to check and change diff oil etc.

[militantmandy]

MX51ROD said:

Thanks for input chaps , pretty sure the diff is where the problem lies , this only happens first time I , move the car off drive when it is cold,any full lock turns once the drive train is warm are normal , as I drive forward the front wheels appear to skip ( used to have a go cart with solid axle and that behaved the same at low speed ) , off to Freelance Mazda shortly , so will get the guys to check and change diff oil etc.

But the diff is on the back!

[MX-5 Lazza]

Like I said before, its the power steering. The dif has no effect on the front wheels. Get the alignment sorted and it'll probably go away.

[MX51ROD]

Sorry chaps dont agree
If the diff is not working correctly then the rear wheels will want to rotate at same rate , so forcing the car straight forward against the steering lock ,instead of the wheels rotating at differing rates to compensate for differing turning circles of the rear wheels , and allowing the car to turn , simples , also as I keep saying .......when the drive train is warm the problem is not there so, power steering is not the issue , and an additional indication of wheel alignment or steering problems would be uneven wear of tyres , front tyres show no signs of abnormal wear

Millitantmandy says "But the diff is on the back!" wow news to me ,and I was always thinking the MX5 was a front wheel drive car !!
Sighs walks away shaking head .

[militantmandy]

MX51ROD said:

Sorry chaps dont agree
If the diff is not working correctly then the rear wheels will want to rotate at same rate , so forcing the car straight forward against the steering lock ,instead of the wheels rotating at differing rates to compensate for differing turning circles of the rear wheels , and allowing the car to turn , simples , also as I keep saying .......when the drive train is warm the problem is not there so, power steering is not the issue , and an additional indication of wheel alignment or steering problems would be uneven wear of tyres , front tyres show no signs of abnormal wear

Millitantmandy says "But the diff is on the back!" wow news to me ,and I was always thinking the MX5 was a front wheel drive car !!
Sighs walks away shaking head .

Started a thread.
Ignored advice.
Told everyone else what the problem was.

What was the point of this again?

My comment was intended as a shade tongue in cheek, but I see we've passed the sense of humour stage now....

[MX51ROD]

militantmandy said:

Started a thread.
Ignored advice.
Told everyone else what the problem was.

What was the point of this again?

My comment was intended as a shade tongue in cheek, but I see we've passed the sense of humour stage now....

My question was to see if my thoughts were correct , but the posts following show a complete lack of understanding on how a locked back OR faulty dif would affect the way a vehicle would behave , as for lack of humour . as I said before...............
SIGHS AND WALKS AWAY SHAKING HEAD .

[militantmandy]

MX51ROD said:

SIGHS AND WALKS AWAY SHAKING HEAD .

Capitalising this does not make it funny.

[MX-5 Lazza]

MX51ROD said:

Sorry chaps dont agree

I've had exactly the same symptoms on 2 MX5s before. One of those with an open dif. The car with open dif always had it - less so after a good alignment and it always went away with new tyres. The current car had it when I first got it but it went away, never to return after a good alignment.

MX51ROD said:

.......when the drive train is warm the problem is not there so, power steering is not the issue

When the drivetrain is warm, the power steering fluid is also warm and the tyres have also warmed.

MX51ROD said:

an additional indication of wheel alignment or steering problems would be uneven wear of tyres , front tyres show no signs of abnormal wear

That doesn't have to be true. And I didn't say that the alignment would be bad, just that the problem can be improved with a better alignment. If there isn't enough camber & caster then the tyre wear might well be normal but the tyres will scrub more, especially at full lock.

MX51ROD said:

Millitantmandy says "But the diff is on the back!" wow news to me ,and I was always thinking the MX5 was a front wheel drive car !!
Sighs walks away shaking head .

You came here asking for advice. We gave advice. You can go ahead and change the dif oil to see if that helps - new dif oil can't ever be a bad thing anyway. Or you could try testing what I've suggested out of my own experience. Try over-inflating the tyres to something ridiculous like 40psi or drop it to 10psi and see if it changes.

[MX51ROD]

militantmandy said:

Capitalising this does not make it funny.

MX-5 Lazza , I am not dismissing your input , Just I have my doubts as to your diagnosis .
if after my visit to Freelance I am proven wrong , I will come back and eat humble pie

[MX51ROD]

Freelance diagnosis :- oil change required , good enough for me .What Mark at Freelance does not know about MX5s is not worth knowing

And now weather has warmed up , problem gone , "Yup normal "says he

Edited by MX51ROD on Monday 15th April 17:19