Disco 1 Pro's and con's of higher side wall on tyre

I will be getting myself some mud tyres at the end of the month (subject to the MOT!) and at present am running BFG A/T's 265/70/16.

I have a 2" lift and running the tyres on modulars with -35 offset to stop any rubbing.

My question is, is there any real benefit in going to the larger 265/85/16's instead of the 265/75/16's that I have been looking at?

I am not an 'extreme' off roader, but do like to play and get muddy (last week I got stuck in a very muddy field and had to self-recover with my winch - AT's are not good in extreme mud it would seem when pulling a trailer with about 1 tonne of mud in!).

Just trying to work out if the extra cost and maybe extra strain on the bearing and gearing will be worth anything?

Guess this has never come up before?

Fit what you want to, as long as you realise that with your setup your steering geometry will be all to cock and your speedo seriously illegal. Don't get pulled by VOSA.

which set up, as at present my steering is spot on, and my speedo again spot on with GPS speed

StuRox said:

which set up, as at present my steering is spot on, and my speedo again spot on with GPS speed

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Standard wheels and tyres are 235/70/16 with those speedo will be accurate. With 265/70/16 speed will be 31.7 MPH at indicated 30. 265/75/16 32.8 at indicated 30. 265/85/16 35 MPH at indicated 30. 70 MPH actual speed at indicated 60. I think your GPS is broken. And it is the speedo that needs to read correctly i am afraid. But carry on you know best.

nope have a couple of GPS devices - Road Angel and my Garmin, and surprisingly the speedo is actually accurate, so am guessing it was not very accurate when running on standard tyres.

StuRox said:

nope have a couple of GPS devices - Road Angel and my Garmin, and surprisingly the speedo is actually accurate, so am guessing it was not very accurate when running on standard tyres.

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Ok carry on.

All vehicle speedo's are designed to be optomistic and can be to the maximum of 10%
Unless your Sat Nav is of military specification I wouldn't rely on that either as a speed indicator, and also not a direction indicator, in my past experience of them.

discool said:

All vehicle speedo's are designed to be optomistic and can be to the maximum of 10%
Unless your Sat Nav is of military specification I wouldn't rely on that either as a speed indicator, and also not a direction indicator, in my past experience of them.

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Correct, up until an EU directive in 1999 which came into force in 2001 in the UK. All speedometers had to be accurate to plus or minus 10% at an indicated 30 MPH. After that the actual speed can be 10% less than the indicated speed but never more. A mark 1 Disco will be subject to the old standard. Even so, if fitted with 265/85/16 tyres the speedo would read 30 MPH at a road speed of 35 MPH and 60 MPH at an actual road speed of 70 MPH. So well outside the law. Doesn't matter how many sat navs he has, if the speedo is not reading as it should the vehicle contravenes the construction and use regulations. And is illegal to use on the road. Nit picking maybe but never the less fact.

Taller tyres look cool, and will give your axles/diffs more clearance.

The bigger the tyres the slower your acceleration will be, and as mentioned speedo will be out slightly.

I've got 285/75/16 Fedima Siroccos and I've noticed no change in the speedo being out or steering changing. If anything it made my speedo more accurate to the Sat Nav. Noticed a change in acceleration and top speed but I turned the fuel pump and turbo up and you don't want to be going fast in a 27 year old Land Rover any way haha!

I also have 2" lift and -35 modulars.
Tyres are Maxis Bighorn (mud tyres) 255/85/16. Tall enough for clearance especially deep ruts on Salisbury plain, but also narrow to bite in bottom of rut.
I have an auto box and the only downside whither these tyres is the gearing where the vehicle drops down to third more often than before.
My A/T,s are BFG 235/85/16 and do not have gearing problem.
If you go 265/85/16 then they will be even taller.
You can always deflate for a bigger footprint if you get stuck

well, I have had no real issues with clearance with my 70's and 75's will give a slightly higher stance, although not huge, so will probably just go with those and not the 85's and then no issue with the speedo etc, as at present it is fine.