KuHL 951

Is there any chance of LSD damage if driving with the donut on the rear for very long? I know this would tear up a Torsen LSD on my Miata in no time. With the clutch type LSD is this a concern if the OD of the rears are uneven. Just thought it would be good to know even though I just carry a can of fix-a-flat, AAA card, and have a sub in the tire well.

Steve

Sam Lin

With any form of LSD it's a bad idea to drive with different OD rear tires, it causes drastically accelerated wear and overheating of the diff.

Sam

p0wp0w

what does OD mean?
I have the stock LSD but the PO put different brand tires in the front than the rear....

Zu_langsam

i am assuming that OD means outside diameter

reactor2

Yes, having two different size tires on the rear will harm the LSD if they are on there too long.

jim944s2

I think you could create so much heat (w/ the clutch type diff) that you could do damage to the entire tranny. Even hard track use w/out the cooler can damage the tranny.

James Herne

p0wp0w, you must be kidding... Of course there is no difference if you have different brand tyres on front and rear. Important here is that the 2 rear tyres are the same. For example, if you drive for a long period with a spare tyre on the rear (which outside diameter might be different), then it might not be so good for the limited slip differential.

KuHL 951

Thanks to all. I figured that the mismatch wouldn't be good. It's funny though neither the Porsche or Miata owners manuals even mentions the potential damage. Repair of a Torsen type LSD is mega $$$ from driving only a few miles to get a tire repaired. Sounds like the Fix-a-flat or AAA is really the way to.

Zu_langsam

or move a front to the rear and put the spare on the front- stay away from fix-a-flat. nasty stuff

Perry 951

And most of it is corrosive... not good for aluminum rims.

Go for AAA and a good cell phone.

Sam Lin

Well, is the spare really a different diameter when inflated?

Sam