Fitting a tyre size different from OEM

Hector Mildew

Can changing to a tyre different to the OEM (or recommended size) cause any problems (handling, gear ratios, etc.) or have warranty or insurance implications?


I have a 2011 Prius with 17" 215/45 tyres which are due a change. There are more options in the 205/50 size which according to an online calculator would be 1.8% larger in diameter than the current tyres.


Toyota also supply the Prius III with 15" wheels and 195/65 tyres which are practically the same diameter (0.4% diff) as 205/50 r17 so I’m guessing that it wouldn’t be a problem but thought I’d check here.


Thanks

colm_mcm

Are you changing all 4 together?

Hector Mildew

colm_mcm wrote: »

Are you changing all 4 together?

Yes, should've mentioned that!

colm_mcm

I'd horse away with the other ones if I were you.

Hector Mildew

colm_mcm wrote: »

I'd horse away with the other ones if I were you.

Do you mean stick with 215/45?

colm_mcm

Sorry, I should have been more clear about what way I'd be horsing!

I'd change size and get the cheaper tyres.

YouTookMyName

Make sure the load rating is equal or higher.

Hector Mildew

YouTookMyName wrote: »

Make sure the load rating is equal or higher.

Current tyres are 87, does a higher rating effect comfort and handling much?

Hector Mildew

colm_mcm wrote: »

Sorry, I should have been more clear about what way I'd be horsing!

I'd change size and get the cheaper tyres.

Thanks I'll put my money on that horse so

Jesus.

Following on from the old tyres NCT thread the other day, I just happened to look at the tyres on the car. All five of them (incl spare) are different brand names. Is this unusual?

(Sorry for hijacking your thread Hector)

MuppetCheck

Nope, have you ever replaced them? If so they should be done in pairs.

Jesus.

Replaced two since I got the car. Got them from the same guy but he obviously must stock more than one brand considering they're not the same.

(Just asked him to put another tyre on)

Cucullan

Jesus. wrote: »

Replaced two since I got the car. Got them from the same guy but he obviously must stock more than one brand considering they're not the same.

(Just asked him to put another tyre on)

Were they new or second hand tyres you bought?

OP changing the tyres would be fine, you speedo will be slightly different, 100kph will be just under 102kph, no real biggie...

Spike Witwicky

Hector Mildew wrote: »

Can changing to a tyre different to the OEM (or recommended size) cause any problems (handling, gear ratios, etc.) or have warranty or insurance implications?

Insurance or warranty i don't know but switching to a different size tyre will affect fuel consumption and handling. For better or worse depends on the size. However the size difference you're talking about should the effects would be minimal i'd say.

Hector Mildew wrote: »

I have a 2011 Prius with 17" 215/45 tyres which are due a change. There are more options in the 205/50 size which according to an online calculator would be 1.8% larger in diameter than the current tyres.

Personally i'd switch to the 205/50's. It will make the ride a bit softer and i doubt would cause any rubbing on the arches.

Hector Mildew wrote: »

Toyota also supply the Prius III with 15" wheels and 195/65 tyres which are practically the same diameter (0.4% diff) as 205/50 r17 so I’m guessing that it wouldn’t be a problem but thought I’d check here.

If switching to the 15" wheel is an option i'd go for it. Imo 17" wheels are too big for a car that's main point is fuel economy.

Jesus.

Cucullan wrote: »

Were they new or second hand tyres you bought?

Brand spanking new.

Cucullan

Jesus. wrote: »

Brand spanking new.

You should tell that they fitted two different tyres the last time and that you want to have two the same on the front unless he told you before he did the work that he was fitting two different tyres? Were they the same price? What make were they?

No Pants

I would ensure that the tyres on each axle match as closely as possible.