Thread: Spare different to rolling tyres - what to do?

From memory the recommended life of a tyre is 7 years but they probably includes exposure to UV, for occasional use ie emergency i would be happy to use a different diameter tyre for a spare.

Originally Posted by loanrangie

From memory the recommended life of a tyre is 7 years but they probably includes exposure to UV, for occasional use ie emergency i would be happy to use a different diameter tyre for a spare.

As long as you were not 4WDing requiring the centre diff to be locked or had locker diffs fitted.

in order to be roadworthy spare needs to be same size as fitted to the car

I still have the original Mitchy as a spare also. It has had the exact life yours has had. I run 4X 255 65 R16 Michelin Latitude Tour HP.
However I have a full set of 5 rims and tires for when I go off road, 265 75 R16 Micky Thompson MTZ. I needed my spare half way through a trip recently and was glad I had made that decision.

Even though the diffs are open and it is possible to drive on different size tires, why give the diffs are workout? Especially when off road.

But to answer your question in my opinion:

It depends on what tire size you are happy with. It you are OK with the 235/70/16 I'd probably just buy a set of 4 and not bother rotate the spare due to its age but at least it is the same size. (also it may not be available as you say)

But if you prefer the 255/70/R16 i'd probably buy 5 and turf the spare.

Originally Posted by Outback 1

in order to be roadworthy spare needs to be same size as fitted to the car

It needs to be the same "diameter" Sorry to be pedantic but it is different.

that would then require you to travel at a lower speed which is why space savers and narrower tyres are restricted to 80kph

It was suggested to me by a friend after I complained about the price of a new motorcycle helmet that "If I had a Ten Bob head buy a Ten Bob helmet" I believe the same goes for tyres
and women don't mess with either.
5 x same size, right spec, right pressures, rotated. 😊

+1 for that^^^, but anyway you need same diameter(more correctly circumference) spare cos otherwise if you'll be forced to use it you might not be able to dirve it unless you remove the ABS pump relay cos the TC will kick in all the time...to not mention how dangerous is for the brakeing distance as you might end up pushing a pulsing pedal and watching how the car keeps rolling... and that can happen even with same circumference but different profile....though if the difference in diameter(circumference) is too big you'll get the 3 amigos with sensor signal fault with reduced ABS activity(which includes TC and EBD too)