Different tyre sizes

[azzah]

Recently purchased a second hand ex NSW highway patrol xr6 turbo with the typhoon wheels and I noticed yesterday that my spare tyre is a different size to the tyres on the car. My spare is 245/40 R18 and the rest of of my tyres are 245/45 R18.

 

Am I right in thinking that if I ever get a flat and have to put the spare wheel on that I should minimise the time I spend driving with that different size tyre or is it perfectly fine to drive on.

 

Also which is the size that would have been provided from factory 245/40 or 245/45

[ROB83R]

Put it on the front if you have to. 

It'll also affect the way it holds gears. 

check that post out. Explains what will happen. 

Took some digging to find that one. 

Edited 12/10/16 12:57 PM by ROB83R

[azzah]

Thanks if it's going to cause issues I'd rather make sure my spare tyre and the ones on the car are the same size.

 

Was at a tyre shop the other day (before I found out about the spare) and they did say the tyres on it now are cheap and nasty (but plenty of tread) so I think the dealer has just put the cheapest tyres on they could so I'm tempted to piss them off and just get 4 new tyres that match the spare

Edited 12/10/16 01:12 PM by azzah

[arronm]

245/40 is the  Correct size.  245/45 Will be ok.  Just keep the spare on for a mInimum time. 

 

Or just smoke them up and get new ones.