tom1979

Well-Known Member
Full Member
Does anyone know the standard height of defender tyres (in inches)? I am running 33" tyres and am trying to work out mpg, but I am travelling further than the vehicle is measuring because of tyres. If I can work out the difference I can get a more accurate mpg.

Using the vehicle readings I'm getting about 21mpg.

Many thanks
Tom.
 
What size is a defender tyre anyway??

Can't believe we've had another tyre question FFS :mad:

just google tyre size calculator ya lazy barsid... :(
 
A 90 is normaly 205/16 or you can spec them with 7.50/16 or new equivilant 235/85/16.

A 110 should be 7.50/16 or equivilant 235/85/16

Mine are off 110 and ar 32 inches high
 
Aww, there there

Trouble with gps is that it will show the correct miles now but speedo with original tyres may have been 10% fast so what to do?:)

are you for real?

to work out mpg you need to know two things

distance covered and gallons used


it dunt matter what tyres you've got on does it? :p
 
are you for real?

to work out mpg you need to know two things

distance covered and gallons used


it dunt matter what tyres you've got on does it? :p

Thing is he was wanting to know what the difference was when bigger tyres were fitted so if his old fuel consumption was based on a speedo 10% fast then an accurate gps miles/galls isn't going to help
 
Thing is he was wanting to know what the difference was when bigger tyres were fitted so if his old fuel consumption was based on a speedo 10% fast then an accurate gps miles/galls isn't going to help

so the question isn't what mpg is he getting now but what mpg was he getting before fitting the new tyres?
 
are you for real?

to work out mpg you need to know two things

distance covered and gallons used


it dunt matter what tyres you've got on does it? :p

The vehicles are setup for a certain tyre size so if run larger diameter tyres it will read less distance than you are actually travelling. GPS is probably the most consistent way of measuring it. Even easier would be to just keep filling it up and not worry about it.

Thanks of all your replies.
 
It's possible to be getting low mpg depending on tyres. With 285/75 muds I would get around 60miles for £20 (less than 20mpg)
 
The vehicles are setup for a certain tyre size so if run larger diameter tyres it will read less distance than you are actually travelling. GPS is probably the most consistent way of measuring it. Even easier would be to just keep filling it up and not worry about it.

Thanks of all your replies.

i changed my tyres to a higher profile and as a result the speedo reads exactly the same as gps.
this is annoying when driving in traffic as they are all doing 5 mph less than i want to go.


i know exactly what you were trying to achieve, gps would've sorted the calculation out easily if you had done it before and after the tyres were fitted but hey ho.

it kept a few of us happy for ten minutes :)

no offence intended Landowner ;)
 

Similar threads