'Up' sized tyres on 20' Rims?

[YvesD]

Has anyone fitted 255/50 tyres on their stock 20 inch rims?

For such a large, heavy, adequately powerful car I feel the 235/55 tyres are abit skinny, especially as I tow with mine, would like a bit more rubber on the road.

Thoughts?

[NemesisUK]

Does the handbook show the larger size as an option? If not there may not be space, your insurer may have an opinion on the modification

[YvesD]

No but the 8j rim can take the wider tyre and there looks like there's plenty of clearance both sides to me.

I've modified every car I've owned pretty much in some way and yes you're right, always inform the insurer 👍

[Spock66]

2 hours ago, YvesD said:

Has anyone fitted 255/50 tyres on their stock 20 inch rims?

There is certainly a much wider choice of tyres in this size.

[YvesD]

12 hours ago, Spock66 said:

There is certainly a much wider choice of tyres in this size.

👍

[Fsport]

Yes you can easily fit 255/50.

I have recently installed 255/55 tyres on my Gen 4 RX to get better ride confort and better quality tyres. (255/50 is actually a smaller diameter than the standard setup).

No issues at all.

The OEM bridgestone and dunops available on the standard size are awful.  

[ColinBarber]

4 minutes ago, Fsport said:

255/50 is actually a smaller diameter than the standard setup).

Only marginally, whereas 255/55 is significantly larger. 

[Fsport]

It isn't significantly larger.  Besides, diameter isn't an issue given the massive size of the wheel arch gap on our cars.  It is whether the width will cause rubbing on full lock.  255/55 does not result in any rubbing.

I now get better ride quality, a better fuller looking wheel arch and much better tyres.

All tyres available for the 235 size are average in comparison.

[ColinBarber]

35 minutes ago, Fsport said:

Besides, diameter isn't an issue given the massive size of the wheel arch gap on our cars.

Changing the odometer/speedo by nearly 3% is the issue, not the physical size.

[Fsport]

My speedo was approx 4mph slow on original wheels and tyres.  Not sure if Lexus do this on purpose.

It is now is accurate to 1mph so the change is tyre size works for me in this instance.

[NemesisUK]

1 minute ago, Fsport said:

My speedo was approx 4mph slow on original wheels and tyres.  Not sure if Lexus do this on purpose.

It is now is accurate to 1mph so the change is tyre size works for me in this instance.

By law manufacturers cannot allow their speedometers under read, so generally they allow up to 10% over read. 

[Fsport]

Sorry, yes meant it was 4 mph faster as standard.