Different tread patterns on same vehicle?

[thermidorthelobster]

The 101 currently has 8 bar-grip type tyres, size 10-10.5x20.  They're different brands, but the best ones of the bunch are Dunlop Spezial Mils.

Dunlop don't make Spezial any longer, and so far I can't find anybody who can get me a similar tyre in that size.  I can, however, buy a different tread pattern (similar to an All Terrain type) in that size.

The crunch is, if I have to replace all 8, it's going to be costly, plus I'll be throwing away 2 good and 6 reasonable tyres.  The next option has to be buying 2 of the AT-type tread pattern, but this means I'll have different treads on the front 2 than the back 4, and if I have to swap spares around, I could end up with different tread patterns on the same axle.

I'm not too happy about doing this, but if I were to, does anybody know whether that would be illegal or an MOT failure?  I understand that in this size, the manufacturers make the tyres to a good tolerance, so the sizes wouldn't be that different even across manufacturers.

[TimM]

Your not allowed to mix cross ply and radials on the same axel, but I don't think there is any requirement for them to have the same pattern (but don't quote me on that).

This months LRO has a buying guide in there for 101's, and it talks about what tyres are available, it might be worth you getting a copy (unless you have one) or having a read in WHSmiths  

[Henry Webster]

I'd be a little concerned that the rolling radius was different.  If you look at most big off road tyres they very hugely across brands even for the same nominal size.

H

[hobbit]

I'd be a little concerned that the rolling radius was different.  If you look at most big off road tyres they very hugely across brands even for the same nominal size.

H

Agreed if the rolling radius are the same, no probs, if its a permanent 4wd (or 6wd) then the rolling radius will have to be the same, if as i think that one of yours is rwd only in normal use, as long as the 4 are the size no probs

Just if that is the only 4 you have and the others are different radius, changing one would me at least a pair for the sake of the drive axle

[Henry Webster]

101s are permanent 4x4 as std, so I would guess it is at least permanent 6x4

H

[thermidorthelobster]

101s are permanent 4x4 as std, so I would guess it is at least permanent 6x4

Pretty much - you can select to drive the rear two, the front four, or all six, but most of the time it's the front four.

[Sheddy]

As has been said, mixing cross-plys and radials on the same axle is illegal.

Different size tyres on the same axle is illegal.

Different tread patterns on the same axle, whilst not illegal, can cause problems if it is the steering wheels.  I had a problem with one of my trucks which kept pulling to the left.  We checked the tyre pressures, toe in and tracking but all were O.K.  The problem turned out to be that there was a different tyre on the nearside to the offside, that was all that was needed to cause the steering to pull.

Hope that helps.



.

[Lee_D]

bearing in mind any one who stops you will be blind for at least 30 minutes I'd not panic  

If it were I doing the milage you are about to do I'd be looking at what the availability is in the main citys / towns that you are going to and try to get a set of the same here. You can alway use the old ones as spares like Chris and helen did just taking the tyres and putting them on to the spare rim if the need arises. Have you got a good tyre lever and breaker bar? Hi lift will break the bead for you. Get some practice in ready! Carrying two carcases will keep the weight down, you aleady have two spares so fingers crossed you won't need any but best to be prepaired.

Lee

[thermidorthelobster]

Thanks all for information.

The truck already has more than one different tyre type on it, but the tread patterns are the same.  They're all cross-ply.  I'm reliably informed by a guy who imports them that (unlike 900x16s) 10.5x20s are manufactured to a standard size, pretty much, so there shouldn't be any real difference in size over and above what you'd normally get from worn or unworn tyres.

So I think I'll buy two or three of these Czech tyres in the AT-type pattern, and try and keep them on the same axle at least!  Probably the front one as it needs the grip to get round corners...

[thermidorthelobster]

I got a hefty set of tyre levers from Matt Savage, and I'm going to practice on the new set I get, I'll try to fit them myself...  (the levers have already proven useful for getting out a recalcitrant oil seal.)

I don't think I'll have much choice about what I buy, as the size seems unusual.  But I'm expecting the African roadside tyre places to be rather expert at mending whatever mangled heap of rubber I throw at them.  I'll take plenty of spare tubes.

By the way, anybody know who sells spare tubes to fit on a 10.5x20 tyre?  :D

[thermidorthelobster]

I've just ordered a pair of the Czech tyres with the AT tread pattern, and I'll put those on the front, and the best of the bar-grips in the middle, with the other 4 split between the back and spares.

Out of interest, I was recommended http://www.tyre-rite.co.uk for all the fiddly bits - patches, adhesives, inner tubes etc - and they couldn't have been more helpful.

D

[Lee_D]

Did you bung them on yer self in the end? Once saw my Dad doing a Landie 750 tyre.... H'mmm looked like alot of work.

Interested in any tips as it's something I've always wanted to be able to do.

Lee

[tomarse]

Interested in any tips as it's something I've always wanted to be able to do.

Same here!.

I once did a motorbike tyre and it took us about 3 hours and lots of swearing!  :oops: