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[Andy Pont]

Apologies if asking a stupid question - or one that already been answered (that I couldnt find in the search).
I drove in the snow today for the first time in my Omega following a week off work, and managed to get myself stuck in the works car park. When trying to pull away apparently one wheel wasnt 'even trying to turn' while the other started spinning. Does this mean I have a problem with the diff, or are there other factors to consider? Both tyres have the similar (good) amount of tread, and tyre pressures are even. Conditions 'underfoot' looked similar both sides.
I admit to being daft enough to not turn on the snow button as until i got home and looked on here i hadnt realised it only engaged in d - i was trying it while still in p. D'oh!!! 

[albitz]

This is a major weakness in the design of normal Diffs, as used in most cars. If one wheel has less traction than the other, the drive gets transferred to that wheel, hence one wheel will spin and the other not move.
A limited slip diff on the other hand will transfer power to the wheel which has grip.

[waspy]

It's called a "diferencial" Basically when you turn a corner, the inside wheel will turn faster than the outer one. What happened in your case is one tyre will have slightly more grip than the other & thus making one tyre spin.
You would really struggle to drive anywhere without one.

[Boditza]

from the definition tc would help in these situations, altough the dif is pretty faulty this way . best ones are LSD

[waspy]

This should explain it

[media]http://www.youtube.com/watch?v=iBLE0_Sjqw4[/media]

[alank46]

That's not strictly true.  I drove for a couple of years on the road with a welded up diff until I could afford an LSD.  Admittedly one has to take a bit more care on slow wet corners.  In the past several production cars did not have diffs, Trojan is one and I think GN as well.  Probably you are all too young to remember.
Alan

It's called a "diferencial" Basically when you turn a corner, the inside wheel will turn faster than the outer one. What happened in your case is one tyre will have slightly more grip than the other & thus making one tyre spin.
You would really struggle to drive anywhere without one.

[Andy Pont]

Thanks for the replies.

I knew the logic about a differential allowing equal torque to both wheels so that speeds were maintained when cornering - outside wheel turning quicker to compensate for the larger distance around the larger radius. I did not know how this worked mechanically, so hadnt appreciated the effects on poor traction: more slip = more drive to that wheel.

I have learnt something today!! 

[PxMetro]

Thanks for the replies.

I knew the logic about a differential allowing equal torque to both wheels so that speeds were maintained when cornering - outside wheel turning quicker to compensate for the larger distance around the larger radius. I did not know how this worked mechanically, so hadnt appreciated the effects on poor traction: more slip = more drive to that wheel.

I have learnt something today!! 

Just for interest, rail rolling stock have a solid axle with no diff, but still go round corners ok, but they get round this by effetively making the outer wheel a larger diameter than the inner wheel. (Left corner the wheel dia would be slightly smaller) This is done by tapering the contact surface of the wheel with the inner edge larger than the outside, so, as the axle assembly moves to the right during a left hand turn, due to centrifugal force the wheel moves up on the taper, and the opposite happens in the inner wheel, similar to a diff. This also helps keep the wheels central on the tracks when traveling in a straight line. 

[2woody]

ok, so the point of a differential is that it's a device to allow inner and outer wheels to follow the same corner without either having to slip across the tarmac, thus wearing out the tyre.

BUT, the cheapest way to achieve this ( the "open" diff ) means that the faster-spinning whell gets all of the torque, hence the proble that you've been experiencing.

the Limited-Slip-Differential allows only a limited amount of speed differential between the two wheels before locking up - the amount is called the locking factor

there are other types of locking diff, such as "torsen", where the output torque is proportional to the speed differential and so on - maybe ten different types for a manufacturer to choose from.

[pembsomega]

It's called a "diferencial" Basically when you turn a corner, the inside wheel will turn faster than the outer one. What happened in your case is one tyre will have slightly more grip than the other & thus making one tyre spin.
You would really struggle to drive anywhere without one.

wrong way im affriad boss, the outer wheel spins faster, its got further to go round the courner than the inner wheel......

[Andy Pont]

So can anyone recommend a particular LSD that would fit my 2.0 auto? Or know where I can get one from without paying a fortune?
I only bought the Omega in april, and until the snow fell have loved it. While most of the 10 or so previous cars i have owned (and driven all winter) have been front wheel drive, I have never once been stuck in the snow. This week it happened on two consecutive days. the snow has been significant but certainly not the worst I have driven in. Its frustrating knowing that I am likely to have to dig myself out, and rely on others to give me a push, every time we get bad weather and also knowing that if one wheel even thinks its on snow it will get all the drive!! (exaggerating, but you get the point)

[2woody]

LSD only ever fitted to SOME police Omegas.

you can build one out of an Omega diff and a Carlton/Senator LSD.

either way, expect to be paying £400 or so.