new tyres on back?

"Davey" gurgled happily, sounding much like they were saying:

And here's why it's not always that simple.

Just curious. Does this apply to my rear wheel drive car too? (Sierra). I feel I need more grip on front when on tight fast bends. Back of car do its worst and I'm happy with that, but I feel happier with more grip at front so would initially prefer the new tyres on front, but would put on fback or force myself to buy all four if its really important for new to go on front. Sorry not enough time to read up on it myself.

Mark

In message , Fred writes

It depends.

Some manufacturers of performance cars (and, I think, other cars) explicitly state not to rotate tyres front to back or vice versa in the owner's manuals, some say you can and others don't advise it but give advice on what to do if you really must!

Read the manual, although you're unlikely to be driving the car at the limits of its handling it so it shouldn't make much difference.

Plenty of arguments for and against, my personal opinion is to never move worn tyres off the 'axle' they have been worn on because tyres wear to suit the geometry of the suspension and will give sub optimal performance on a different corner of the car.

They will also wear faster if there's a difference in suspension geometry so you may actually be reducing the life of the tyre and costing yourself more money sooner.

If you *understand* what the tyre manufacturers are recommending, Isn't that a perfect example of why you need the best tyres on the rear.

It is the same whether front or rear wheel drive, always have the best on the back is the overall safest for most drivers under most circumstances. The rationale being that the most likely tyre to suffer damage will be a rear in which case there is more material to penetrate before it goes down and a front wheel understeer situation is easier to understand and get out of for most drivers whereas a rear wheel skid doesn't easily recover without significant driver input.

I find with my 4x4 sierra that it is very sensitive to how much junk is in the trunk and handles much better with nothing in the boot and low on fuel, at present it has michelin on the front and rubbish tyres on the back, the handling is appalling since putting the cheapos on the back (they came free with a scrap car, I would not choose to put horrible tyres on usually !!)

No.

Agreed.

Since most of the braking is taken up by the front tyres, clearly you get the shortest braking distance by putting new tyres on front. It is also easier to even out the wear by putting new tyres where the wear is highest, hence greater probability of matching wear between front and rear. Resulting in regular visits to tyre change for 2, then 4, then 2 tyres etc.

If you put new tyres at the rear, you wil have irregular visits to tyre depot, and tyre wear will be out of sync. But depots will sell more tyres. Maybe that's the real reason...

Why would that sell you more tyres, the rears dying of old age rather than being rotated to the front will sell more tyres.

What the clip demonstrates is that - for the thousandth time of repetition - it depends on the car.

They will sell more tyres because people are more likely to downgrade nearly worn tyres just get the business done on the day. And tyres are more likely to be out of sync.

E.g. if you change front tires, you might get a nice pattern for new tyres

2,4,2,4 ect. Changing rear only will spoil that pattern.

The braking distance doesnt vary that much between old and new tyres in dry conditions .

"steve robinson" gurgled happily, sounding much like they were saying:

Bollocks.

Old tyres aren't just worn down, they're also thoroughly heat cycled. The tread itself might not make a lot of difference - hence road tyres being shaved for track use - but old tyres are certainly a lot less grippy than new.

Only if your tyres wear at exact multiples of each other, if you rotate the rears to the front each time then you'll only ever buy two at a time. (Unless you have a car that wears the rears faster but if you've got a

2.8i Capri then you'll still want the new ones on the back)

Tyres operate best at specific temperatures depending on the compound of the rubber , either to cold or too hot and they dont grip.

Shaving a tyre stops it generating and retaining exessive heat

Road and track use are completly different

Thanks for that. I'll follow the guidance if I fit only two tyres. I'm more than happy driving a oversteeering rearwheel drive that is a bit wobbly at the back, in fact I enjoy a little bit of lost rear traction on a wet roundabout, but I'll stick with the received wisdom on this one.

Regards Mark

So its about having more grip at the back than the front, irrespective of wear (providing its safe tread depth of course). Presume this would also apply to a set of old tyres of varying depth/quality. Best on the back. All makes sense now.

Thanks folks. About time a public info campaign was run by those wankers in power to make this info more public.Won't hold my breath.

Mark

My understanding is simply that having more tread on the rear tyres would provide more grip. The argument being that losing grip at the front of the car would be more noticable and controllable before it's too late and you've lost it, proper. Losing grip at the back being less noticable and more difficult to regain control once lost.

There is always an exception to the rule, but the above would be sensible thinking on your average front wheel drive UK car.

My point is that people will usually 'downgrade' the other set if they are nearly worn, but not as much as the most worn. Usually you can get special offers for changing all four tyres.

[1] downgrading is an expression used for airline servicing. Airlines often downgrade parts in order to save on stop time.

Must say I am much happier about losing grip at back than front, but perhaps that is just me (RWD Sierra). Ok, so I'm only talking slight loss of grip and steering to correct. Not got any experience of loosing front grip as not owned a FWD for 25 years. I can feel the back going at very first sign, but front not so obvious for me. Horses for corses but I'll still folow the advise to put best tyres on rear.

Mark