Would the spare be OK for a 220 mile journey

[urmm]

Im at my in laws 220 miles away and have just discovered that one of my front tyres are gone. A quick look at the mobile tyre fitters and they wont cover the bank holiday weekend and i need to be home in time for work. My spare is practically new but is 215/55 16 and my others are 235/40 18. According to a rolling radius calc The rolling radii is almost the same 313 vs 312 mm while the rolling circumference is 1961 vs 1968 mm. Any opinions

Cheers in advance

[sunbeam_alpine]

I think you'll be fine, but probably best to take it steady.

I would probably try to put the mismatched tyres on the non-driven axle to minimise stress on the diff.

[GTIR]

sunbeam_alpine said:

I think you'll be fine, but probably best to take it steady.

I would probably try to put the mismatched tyres on the non-driven axle to minimise stress on the diff.

Stress on the diff?

Why, that's what diffs are for.
What about when your turning a corner, one is turning faster than the other which what will be happening with different size wheels.

You'll be fine op. Don't worry about it but equally dont drive like a nutter!

[GreigM]

I'm with GTIR - no issues - think of all those small size space savers - they are rarely the same size as the wheel they are replacing. You'll be fine, probably won't notice the difference....but still drive carefully.

[davepoth]

Have you checked with non-mobile fitters? A 20 mile drive is better than a 200 one...

[redstu]

So you have lost a front tyre? It's "gone" as in missing?

[mcford]

Better if fitted to the rear in my opinion, as the fronts do more, braking, steering and maybe driven.

[urmm]

Gone as in flat with a great socking nail in it. I really doubt you can save it

[LeoSayer]

It's no different than driving a space saver, just avoid hooning and I think you'll be fine.

[philoldsmobile]

BE VERY CAREFUL if you have a limited slip diff, fit the spare to the other end. fitting odd size wheels to an lsd will result in greatly increased wear.

[urmm]

Car is rwd and the spare is on the front, when you say take it easy, is 65-70mph OK

[5paul5]

What you going to do if you have a puncture on the way ?

[philoldsmobile]

urmm said:

Car is rwd and the spare is on the front, when you say take it easy, is 65-70mph OK

Should be fine. Avoid harsh cornering or braking, but you wont damage anything with the odd wheel on the front.

The reason for being very careful is odd size wheels on a limited slip diff can toast the diff very quickly. as your car is RWD and the odd wheel is on the front, i doubt you'd even notice it, much less do any harm

Edited by philoldsmobile on Saturday 1st January 15:40

[mmm-five]

GreigM said:

I'm with GTIR - no issues - think of all those small size space savers - they are rarely the same size as the wheel they are replacing. You'll be fine, probably won't notice the difference....but still drive carefully.

Don't forget that those spacesavers normally have a warning on them about going over 50mph and for no more than 50 miles as an emergency measure. If you're stopped you'll have a bit of explaining to do. And why haven't you got a full size spare - as it seems it would fit in the spare wheel well?

BTW, it wouldn't put any extra stress on the diff than the standard tyre would with 1mm less tread than the other side.

Although do you really want to be using 400lb/ft when you've got odd sized tyres on the front controlling your direction?

Edited by mmm-five on Saturday 1st January 16:04

[Ozzie Osmond]

urmm said:

Car is rwd and the spare is on the front, when you say take it easy, is 65-70mph OK

No.

You've got two problems, the definition of temporary use and the dimensions of the tyre. "Temporary use" means just that - getting home or to the tyre fitter.

Construction and Use Regulations 1986. Regulation 26 prohibits mixing tyres of different types on an axle (usually crossply and radial) and regulation 27 covers condition and maintenance of all tyres.

"(1) a wheeled motor vehicle fitted with a pneumatic tyre shall not be used on a road, if :-

(a) the tyre is unsuitable having regard to the types of tyres fitted to its other wheels;"

"(3) Paragraph (1)(a) does not prohibit the use on a road of a temporary use spare tyre, unless the vehicle is driven at a speed exceeding 50 mph."

[urmm]

Thanks for the replies. Just to say that the spare is on and it is the same overall diameter as the other tyres (the tyre not the rim therefore the rolling radius is the same). The only difference is the width (215mm vs 235mm - 2 cm). The AA man said it was OK said if i take it easy (The jack broke while i was changing the tyres - dont worry the car didnt crush me or fall down it was just the handle)

I could try to see if tyre centres are open but I have a horrid feeling they wont have the tyre I want and I dont want to be stuck with a different make of tyre compared to the others, particularly of the same axle (I take that seriously)

Edited by urmm on Saturday 1st January 19:44