Mixing tyres

[cityofmyths]

Hi guys,

Looking for a bit of advice on tyres. Currently travelling South America and for one reason and another I've ended up with different tyres. Here's the question: can I mix a Coopers Discoverer S/T All-Terrain, M&S, Load Range D, on the same axle as a BFGoodrich All-Terrain, M&S, Load Range D. Obviously their tread patterns vary a bit, otherwise same spec. The tyres are new.

Any advice much appreciated.

Cheers,

James
cityofmythsriverofdreams.com

[Gipper]

What vehicle are they on and are they all the same size?

Just to update this post, the tread pattern doesnt matter so much, the important factor is the physical tyre height if you are running in 4wd with a CDL engaged (or equivilant) then you will get even more transmission wind up on a firm surface with different height tyres on different axles.

If you are running rear wheel drive normally and 4wd occasionally on a loose surface it would be fine. Try and keep 2 of the same brand (height) tyres on the same axle, this will reduce the amount of heat build up in the differentials. I normally put the tyres with the best tread/grip on the front axle.

Hope that makes sense!

[cityofmyths]

Hi Gipper,

Thanks for your response. The vehicle is a Land Cruiser model 78, so normally run in two wheel drive. The tyre size is 285x75x16 for both the Coopers and the BF Goodrich. I was thinking of running the Coopers and a BFG on the front axle and the two other BFG's on the rear. I had a notion it would be better this way re the transmission wind-up but wasn't sure. It seems you agree this would be an ok solution.
Thanks for your advice.

Cheers,

James
cityofmythsriverofdreams.com

[tacr2man]

Originally Posted by cityofmyths

Hi Gipper,

Thanks for your response. The vehicle is a Land Cruiser model 78, so normally run in two wheel drive. The tyre size is 285x75x16 for both the Coopers and the BF Goodrich. I was thinking of running the Coopers and a BFG on the front axle and the two other BFG's on the rear. I had a notion it would be better this way re the transmission wind-up but wasn't sure. It seems you agree this would be an ok solution.
Thanks for your advice.

Cheers,

James
cityofmythsriverofdreams.com

Trans wind up is not a factor with the vehicle you have (ie part time 4wd)
You would be better with the two same tyres on front axle , and run the dissimilar tyres on the rear axle . There will be less likelihood of any effects to the steering that way . Even with a full time 4wd wind up is only a factor when running with centre diff in lock , which should only be done on low traction surfaces anyway , eg mud or snow , or bush tracks which are loose surface to aid stability . HTSH

[moggy 1968]

I used to think it was best to have the good tyres on the front, but have now seen convincing evidence that this is not the case. Here is one example, there are others:

Vicki Butler Henderson explains why new tyres should go on the rear - YouTube

For those that don't know Vicky Butler Henderson is a rally driver, so knows how to handle a car.

transmission windup should never be a problem in either a part time 4wd or Full time 4wd because you shouldn't be running with the 4wd engaged (in P/T) or diff locked (F/T) on a grippy surface!!

The main problem is that the different tread patterns and tyre characteristics (sidewall strength etc) can give unpredictable handling, so generally it is frowned on to mix tyres on the same axle, but if you take it steady yuou should be fine, needs must and all that.

[tacr2man]

The VBH thing is for most drivers of modern passenger cars , with little car sympathy or ability to deal with loosing the rear end . What she didnt show you is what happens with worn front tyres when you encounter sufficient water and speed to aquaplane on a bend , the front end goes and you end up going straight on into the scenery . Having new tyres on front raises this speed a lot higher so its less likely that you will be at a speed that this will occur . I would much rather lose the rear end first than the front .

I would say from a handling point of view it would work better with same tyres on front and the disimilar on rear what ever the state of wear . Dont mix cross ply and radial on same axle tho !!