Calling all the tyre guys...

could I have 750r16's on the front and 235/85 r16 on the back of a defender of will the slight difference in size cause problems???????????


750r16 = 32.1" dia
235/85 r 16 = 32.2" dia

I would have thought it wasnt adviseable, however it will cause most probs in difflock, wont it?

The landy its for will spend 99% of its time one the road, as you say if difflock is sed one set will push the other set and **** the trasferbox or diffs up,

was wondering out of difflock, will the slight wind have cause any problems,

Got 2 good tyres on the defender now, and still have 2 good tyres from the disco

iannotts said:

could I have 750r16's on the front and 235/85 r16 on the back of a defender of will the slight difference in size cause problems???????????


750r16 = 32.1" dia
235/85 r 16 = 32.2" dia

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Not sure why you'd want to and I'm guessin that as long as you removed one of the prop shafts it ud probably be ok

Bromsgrove Defender said:

Not sure why you'd want to and I'm guessin that as long as you removed one of the prop shafts it ud probably be ok

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mondo mode if definatly out of the question

the reason why is in post 3, saving a few quid

I would have thought the centre diff could cope with such a tiny size difference but I'd be worried I was doing some mischief somewhere so I'd keep it to a short term "get you home" type of arrangement.

Yeah realised that as soon as I saw post 3.

Am just bloody slow at typin

ffs 0.1" is less than you get after a while of differing wear rates on the same tyres.
I've got the same tyres front and back, but they've got about 5mm difference in tread depth, so that's 10mm in diameter - no problem.

hughesy said:

I would have thought the centre diff could cope with such a tiny size difference but I'd be worried I was doing some mischief somewhere so I'd keep it to a short term "get you home" type of arrangement.

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I seem to recall from somewhere that the centre diff can cope with 5 mile an hour difference but thats only for brake test and loadin on to flat bed not for drivin around.

Treworgey 90 said:

ffs 0.1" is less than you get after a while of differing wear rates on the same tyres.
I've got the same tyres front and back, but they've got about 5mm difference in tread depth, so that's 10mm in diameter - no problem.

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Good point.

you u say its ok then trew?

Bromsgrove Defender said:

I seem to recall from somewhere that the centre diff can cope with 5 mile an hour difference but thats only for brake test and loadin on to flat bed not for drivin around.

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It's 5 Km/Hr, which is equivalent to a big difference in diameter - somebody can do the maths if they like.

iannotts said:

you u say its ok then trew?

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From the point of view of the centre diff, yes.
I wouldn't do it myself though, because you might get some weird handling due to the different tyre construction and grip.

Treworgey 90 said:

It's 5 Km/Hr, which is equivalent to a big difference in diameter - somebody can do the maths if they like.

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Ah stand corrected.

Thanks Trewy

So at the end of the day you probably can do it but I wouldn't cos I likes to have all the same tyre pattern never mind size
(cue some editting )

You will have no probs at all, as a 235/85r16 are classed as a direct replacement for 750 r16 the whole point of the centre diff is to deal with difference of rotation between front and rear wheels on a hard surface eg when going round a corner etc.
You would not use diff lock on a hard surface , and on a slippery surface , you would be getting different rotational rates on all four wheels anyway

p.s. you are more likely to experience handling problems if the tyres are different ply ratings

0.1 inch difference in the circumference is going to make bugger all difference in Land Rover. Is the width of the tyre about the same?

Reading the post there is another problem that i didn't think of... the ply rating

looks like i have got to get my hand in my pocket

unless anyone has 2 235/85 r 16's knocking around

The only thing to worry about is having the same circumference of tyre ( distance round the around the outside) not the wheel diameter, and then all the wheels will be covering the same distance. If your stuck just measure round the outside of the tread with a tape to match them up. Mick.

discoverynewby said:

The only thing to worry about is having the same circumference of tyre ( distance round the around the outside) not the wheel diameter, and then all the wheels will be covering the same distance. If your stuck just measure round the outside of the tread with a tape to match them up. Mick.

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Its not the only thing to worry about there's tyre make up and differing tread patterns, the state of the economy, national debt third world poverty, Is the pope gay etc

Bromsgrove Defender said:

Its not the only thing to worry about there's tyre make up and differing tread patterns, the state of the economy, national debt third world poverty, Is the pope gay etc

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the popes gay f*ck i've just found out he's a catholic