goodyear mt/r's

Typical diameter for a 285/75/16 is 834mm.
Typical diameter for a 235/85/16 is 806mm.

The 285/75 means that the tyre width is 285mm, side wall height is 75% of the width.

The 235/85 means that the tyre width is 235mm, side wall height is 85% of the width.

The /16 on the end is of course the rim diameter.

The 235/85 would have more give sideways in the wall of the tyre and may not feel very stable for some drivers, but these would have less drag on the bitumen and would return better fuel consumption than the 285/75. Can be of benifit in thin snow and also in mud as the tyre will bite through fairly easily.

The 285/75 would being a wider tyre with a lower side wall height will provide better road handling but with the increased drag on the bitumen they will increase fuel consumption slightly. Can be of benefit in sand and heavy snow as tyre will tend to float on the surface, they will balloon or bag out easilt with reduced tyre pressures.

My personal preference would be the 285/75 as long as they will fit on the vehicle and are suitable for your rims. Of course it's all up to you and what sort of driving you do.

Regards, Mark

Thanks Mark

I had a idea the second numbers had something to do with the first but wasn't sure.

CheersFidei defensor

Rosco

Just put Goodyear MT/Rs on my patrol but went for the 33x12.5x15, very comfortable tyre and no rubbing on full articulation except for small rub on inner arch at rear, nothin to worry about. For $265 a tyre.

can't agree with any of that I'm afraid.
Have done at least 3 trips between Port Hedland & Perth (1700 kms) at highway speed and above and no fuel stops due to LR tanks. Last one was on a 45 degree day and no sign of heat at all.
My 285/75R16's are now 14 months old, have done 35 000 k's and still look like new. They have never gotten hot on long trips and do the job fine on the mud flats. A lot of crew are running these tyres in the Pilbara now for these reasons.

I am losing 1mm per 10 000 kilometres (35 000 km's in last 14 months).
I rotate all 5 tyres every 10K though.
Paid $295 recently at Beaurepaires for a 2nd spare but that was when dollar was 66 cents so there's a fair bit of latitude for bargaining now with dollar at near 80 cents.

and at 35 000 km's they have already outlasted my BFG A/T's but that's another story and we live in different parts of this great country