Driving 4wd with odd tyres

longwalks1

I had to replace 2 x rear tyres on my 4x4 and opted for a slightly higher profile, from 35 to 40. Have ordered 2 more 40 profiles for the front, but at presnt it still has 35's on the front and 40 profile on the rear.
I asked on another forum (car specific) and was almost gunned down for even considering it, even for a few miles saying it would throw out the gearing, destroy the gearbox etc etc

Is this true? Im not planning 100's of miles, just need to drive 4 or 5 miles to get the new tyres fitted to the front. At present, am too worried to move it and am currently considering a mobile tyre fitter (as hugely inflated prices obviously). Any advice please?

neilmcl

Your car's not going to go up in flames in the few miles you travel to the tyre fitter.

However, I would question why you want to change the recommended tyre profiles in the first place?

What is the full tyre size in comparison to the original tyre?

SuperAllyB

Is 4wd not selectable? Anything I've ever driven other than a Land Rover Defender has been.

longwalks1

SuperAllyB wrote: »

Is 4wd not selectable? Anything I've ever driven other than a Land Rover Defender has been.

Unfortunately not

agrinnall

The easy answer (other than just ignoring the merchants of doom on the other forum) would be to get a mobile fitter to come to you.

longwalks1

agrinnall wrote: »

The easy answer (other than just ignoring the merchants of doom on the other forum) would be to get a mobile fitter to come to you.

Hiya I did look into it but they charge an extra £15 per wheel, not a lot I know but this is a money saving forum :beer:

Gloomendoom

If you have full time four wheel drive, the vehicle will presumably have some form of centre differential. If your front axle is constantly spinning faster than your rear axle the centre diff will be working harder than it was designed to do. It will wear out faster.

If that bothers you, fit the same size tyres all round.

loskie

as above depends on the 4wd set up.
Not a good idea in a subaru forester but a wv tiguan with a haldex clutch will be fine.
tell us the car

vikingaero

Depends on the car. For example the original 4x4 system on Volvo 850/V70s were notoriously sensitive to differences in tyre tread depth and just by putting on a brand new tyre could lead to abnormal drivetrain wear.

angel_of_dartford

If this is a land rover freelander 1, pre or post facelift, DO NOT DO IT

This will irreparably damage the viscous coupling unit it the centre of the drive train, it cannot cope with even small differences in tyre size front to back when driven on the road for any distance.

This is a known issue, loads of info at https://www.landyzone.co.uk

Other land rover models, have a switchable differential so it's not an issue

Freelander 2 has a haldex coupling which is electronically controlled and does not suffer the issue.

Can't comment on other makes though

Norman_Castle

Will you also be replacing the spare. If so you need 3 new tyres.