Better to replace all 4 tyres together?

koru

MOT says I need new rear tyres. Costco are the cheapest (£62 per tyre, fitted, for Michelin Synchrome 205 70 R15H, compared with £108 at Kwik-fit, and £74 from mytyres.co.uk).

But Costco strongly recommend that for a 4x4 vehicle it is safer to replace all 4 tyres together. I wonder if this is because they are a US company and are paranoid about litigation risk? Anyone know if there are other authorities who recommend changing all tyres at same time?

vansboy

Current trend, amongst those 'who know about tyres' is, the best/new tyres should be fitted on the rear. You'll find this advice on the tyre makers sites, generally, too.

How much tread depth & how even is the wear, on the front ones - they MIGHT be well within limits, or just legal. The MOT guys, MIGHT have an note on your test paper, to let you know.

If they're good, I'd save a few £$£$, for a while, but think about the buy 3 get 1 free deals some the tyre places have - on specific brands, usually.

& what about the spare - could you keep the better rear one (assuming it is still road legal ) as a get you home fitment, if you had a puncture? You only need buy one new, then.

VB

koru

Thanks. I think you have confirmed I don't need to get all 4 tyres changed, but if they have a special deal I might go for it.

And I'll check how worn the front wheels are. Annoyingly, the rear tyres are mainly fine, The only wear is the inside edges on both tyres. They were obviously poorly alligned when KwikFit swapped them a year or two ago.

Have already been using the original spare - the current spare is only just legal if I have to use it.

Lorian

koru wrote:

And I'll check how worn the front wheels are. Annoyingly, the rear tyres are mainly fine, The only wear is the inside edges on both tyres. They were obviously poorly alligned when KwikFit swapped them a year or two ago.

That's probably nothing to do with the tyre fitting, it's more likely to be incorrect camber or toe angles on the rear suspension. The fitting company will want more of your cash to do a laser geometry/tracking check to assess and fix this. You kind-of have to have it done or the next set will end up with the same uneven wear.

tomstickland

I always replace in pairs since on fwd cars the fronts wear quicker and on rwd cars the rears wear quicker.

koru

Thanks, everyone. I had planned to just get two tyres, but in the end they pointed out some worrying cracks in the rubber of the front tyres, so I did them all. I don't think they did the tracking, so I will get it sorted in the annual service, which is due soon.

golddustmedia

Generally tyres are easily swapped in pairs but 4WD cars are bit of an exception. I don't mean huge SUV Shoguns etc but cars with 4WD systems.
The Vauxhall 4WD train fitted to the Calibra and Cavalier used a viscous clutch which if the tread differed between front and rear wheels meant the front/rear would have more traction than the other and put undue wear on the system leading to expensive bills (hence many now converted to 2WD). The Volkswagen system is a little more stable (as used on Passat and Golf R32 etc) but in general if you've got 4WD it's good to keep an equal amount of road traction on all 4 tyres.

Also there is often a good deal to be had on a set of 4, so much so that recently I purchased 4 when only needing 2 and 1 in the near future and chose to make the best of the old ones the new spare tyre, after all that has to remain legal and is often overlooked. I saved 35% buying 4 compared to 2 making it cheaper than buying the 3 I needed...

Shifty22

Calibras aren't generally converted to FWD, 9/10 they are switched to 2WD (front) because uneven tyre wear on the rear damages the transfer box. Replacement transfer boxes are expensive and with the value of calibras nowadays there is not much point spending big bucks on them.

Tyres should be relatively even regardless of drive wheel setup, uneven tyres can lead to uneven braking, excessive tyre wear and handling issues. The best thing to do on 2wd motors is swap the rear tyres for the fronts when the fronts begin to wear close to the legal limit.

neilmcl

Bear in mind the 4WD systems used on VWs, Audis, Volvos isn't permanent 4WD. For the majority of time the front wheels are the driving wheels, only when there's a loss in traction is power sent to the rear wheels or any wheel that requires it the most.

flyingscotno1

Wow, a 4 year old bump. I think the orginal issues are probably solved!

neilmcl

Well spotted