Tyre sizes

[lightweight]

I know that military Landies run on 7.50x16's. I also know that my civvie 110 Landy runs on 265/75/16's.

 

Question is, what is the equivalent size for the military ones?

 

I want new tyres for the civvie one but want narrower ones with the same height side wall 'cos I like the ground clearance it provides - how do you work it out?

 

And before you say it, no I don't fancy running around every day on bar treads thanks!

[Degsy]

The nearest metric equivalent to 7.50x16 is 235/85/16.

 

[lightweight]

Thanks Degsy, thats exactly what I wanted to know - although I didn't phrase it very well :roll:

 

I think they are also the same overall diameter as the 265/75/16's.

[Degsy]

Probably not much difference, 265 is the width in millimetres, 75 means the sidewall depth is 75% of the width. Just worked it out, the 265 is 1mm smaller than the 235 but these are nominal measurements and variations occur between tyre manufacturers and tread patterns.

[croc]

It is a mistake to think in terms of military and civvie here, they are imperial or metric. When you are deciding which tyres to use you need to decide what you expect of them.

 

An imperial sized tyre has a 100% sidewall to tread ratio so you get a tall tyre for the width, this has advantages off road like clearance, cutting through mud or snow and having a decent steering lock.

On the road you will have a smaller contact area on the road than the same height metric tyre, this makes steering slightly lighter and rolling resistance slightly less, in theory this would give better economy but probably not noticable in practice. On the downside the tall sidewall gives less stability when cornering and the narrow contact area gives less grip in the wet.

Metric tyres have the lower profile which helps on the road but off road the wider lower tyres don't work as well. As most people spend most of there time on the road metric has become the standard fitment, however, Land Rover still list 7.50x16 as an option on new Defenders and they are available if you look for them.

 

A last point, when you get your tyre the rim it is mounted on affects its inflated shape. For example, the swb landrover rim is narrower than the lwb landrover rim so the same tyre would appear wider on the wider rim.

 

 

http://www.landrover.com/gb/en/Vehicles/Defender07/Specifications/Defender_features_and_options.htm?route=_gb_en_Vehicles_overview@__link__ContextLink_4_4#tableheading1

 

http://www.colwaytyres.co.uk/ctraxat.htm