Partial 4-wheel drive systems

[m4rkw]

Slightly off topic but what the hell it's sunday.

My wife has a 2008 rav-4 with a partial four-wheel drive system. I understand that on permanent four-wheel drive systems it's strongly advised to keep all four tyres the same in terms of brand and tread pattern and reasonably close in tread depth.

Does this also matter for these partial all-wheel drive systems? Most of the time the rav is in 2wd mode, it can enable 4wd under certain conditions but it isn't quite explained fully in the owners manual what these are. Additionally there is a button on the dash that locks 4wd mode on, this only works under 25mph and the manual says not to use it unless driving on loose surfaces.

I'm trying to work out if I should be keeping the same brand of tyres on both axles or if it's less of a concern with a partial system.

Cheers,
Mark

[scudney]

I would think you could have 2 brands as long as they are on the same axle,that is one brand on the front and another on the rear without too much bother 

[m4rkw]

15 minutes ago, scudney said:

I would think you could have 2 brands as long as they are on the same axle,that is one brand on the front and another on the rear without too much bother 

That's my hope - thanks.

[PCM]

If it were me - I'd have all 4 the same, for when the 'partial becomes full.

I always think, the only thing between the road and me, are tyres, and I need them to be as safe as a safe-thing that's very safe.

My 2 cents. 

 

[m4rkw]

6 minutes ago, PCM said:

If it were me - I'd have all 4 the same, for when the 'partial becomes full.

I always think, the only thing between the road and me, are tyres, and I need them to be as safe as a safe-thing that's very safe.

I agree with the sentiment, but the 4wd system is only going to activate over loose surfaces at slow speeds, i.e. very infrequently. The reason permanent all-wheel-drive systems require equivalent tyres on all four corners is because the wheels are locked together, if there's a difference then something has to give somewhere and if it isn't the road surface then it's the differential. Over time it can become damaged. I'm hoping though that with this car it's less of a concern.