Alternating front and rear new/flat tires

[ENVIOclev]

The recent tyre replacement/repair discussion, which was luckily closed before someone told us tyres were our sole touch with the road, hinted at a problem that has yet to be rectified.

The "best tyres go in the back," as the old saying goes, and since "best" is usually understood to mean "newest" and "most tread," this is generally accepted as good advice for driving in rainy conditions.

Despite the fact that this was seemingly dismissed by all other posters in the discussion, I find this suggestion believable, having "lost the back end" of a couple of FWD cars due, I THINK, to lift off engine braking in slippery situations.

To add insult to injury, I was once a passenger in a Commer van (not exactly the most stable looking vehicle) that busted a rear tyre on the A1 and no one noticed until the remains caught fire, so I'm not entirely convinced by the official advice that a rear tyre blowout is more dangerous than a front one. Extremely challenging to extinguish.

This is problematic since best tyres on the back (which is valid) contradicts with best bust on the back (if valid), making a decision more difficult than it has to be.

Moderators, please be assured that I am not trying to get around the ban on discussing whether or not it is preferable to buy something brand new rather than something previously owned or repaired. I want to bring up a certain question I have.

Opinions can be somewhat informative.
There is more value in actual experience.
The Holy Grail would be citation of reliable sources.

Even though it's highly technical in nature, I filed it under "discussion" because that's where it originated.

[DenishP4]

Best front or rear is only significant when grip is at its maximum; otherwise, it is irrelevant.

Speed or the road surface (wet, slippery, etc.) might be the cause of the grip limit.

In order to handle steering inputs as well as the centrifugal force produced by the vehicle's lateral acceleration, the front tires endure a greater amount of lateral force than the rear ones.

FWDs are often designed to understeer, which is corrected by increased steering inputs, which is a more natural response for novice or inexperienced drivers. This situation is limited by the front axle's best tires.

In order to adjust for rear wheel slip, the opposite lock must be used; otherwise, the back of the automobile risked passing the front.

Up until the tread was decreased to around 3mm, according to RoSPA research from 2005 (there may be more current data), there was only a little decline in braking performance. 1.6mm is the minimum.

Conclusion: Unless the tyre is already very worn, grip is not really important.

[Rudy7831]

The option does not concern me since it is so unusual for me to purchase a quantity of tires in the double digits, much alone the single digits.

My opinions haven't changed much over the years; I'll always put new tires on the drive axle (provided they aren't ditchfinders), and I'd never want a 4WD to have varying tyre depths anyhow, so it doesn't matter to me where I place the new ones on the other wheels.

This isn't some driving god self-delusional thing, but, the majority of us who know our cars and understand how to operate them have the greatest ability to make such decisions for ourselves. I know that the official position is new to the rear, but as with everything else these days, a single size has to fit all, and it's perpetually centered on those who haven't a clue (which is one of the numerous reasons why our businesses, mine included, have gone around the U bend).

In real-world situations, most FWD automobiles have a propensity to plough straight on, also known as understeering. I don't know about you guys, but I'm a lot happier attempting to correct an overturn than I am realizing the front wheels are no longer doing anything, which is a situation that is very tough to remedy in time.

There isn't a single person in the world who bats an eye when a vehicle with staggered wheels requires a new set of tires; does this mean they are immune to grip issues?

What I don't understand is why so many people choose cars with hugely wide tyres, which requires weight along with decent tread to shift a great deal of water, nonetheless so many people will run their tyres down to just depth...the number of smaller luxury cars (not heavy enough?) such as lower/middle range RWD German marques often fitted with ridiculously wide elastic bands i've seen ceased up in excessive rainfall stuffed down the motorway armco throughout the years have to maneuver into the many many

[NevoBMW320i]

In terms of personal experiences, aged / old (hard) tyres on my current Mazda3 caused the rear end to step out twice in a few weeks on wet roundabouts. Fortunately, no one was hurt on either occasion, but it frightened the crap out of me and prompted me to replace my tyres.

During my study for the change, I discovered that the old (OEM fit) tyres did not have a good reputation in general, and particularly as they aged (despite the wear) in the rain. They were still nice in the dry, although a little loud and uncomfortable.

The new tyres had a considerably higher review rating, which I could confirm to throughout their lifespan. I'd suggest rotating tyres so that the fitted rears (on FWD vehicles at least) receive equal use also helps, since wear exposes 'fresh' rubber, which isn't as harsh as the 'outer' surface if left on that axel.

I only modified the second set due to ages (they were 6 years old, but with approximately 4-5mm tread ish if I recall) and because I was reduction in size the alloy tires from 16in to 15in and thus had to change tyres anyway (one was leaking because the alooy was tarnished, and the others appeared to be doing the same). The tyres were otherwise in good condition.

[bentleygt77]

I've only ever had one tire blow out, and it had been on the back wheel of a RWD car. I definitely noticed it, but I was happy to pull in to the wide side without any trouble. That wasn't because I was a great driver, it was easy.

I've always been more worried about the front tires of a FWD car because they do everything.

[blueWING007]

Just now, bentleygt77 said:

I've only ever had one tire blow out, and it had been on the back wheel of a RWD car. I definitely noticed it, but I was happy to pull in to the wide side without any trouble. That wasn't because I was a great driver, it was easy.

I've always been more worried about the front tires of a FWD car because they do everything.

I once saw the late Eric Carlsson, a veteran rally driver, do a demonstration by driving over a tire knife at 60 mph while holding both hands up through the open sunroof of a SAAB 900.
The automobile kept going straight like a dead end.

[migueldosantos77]

My different cars have never had tyres slide or step out of line in typical weather, wet or dry. I've felt the lightness on black ice and snow as the automobile loses grip. Driving wheels constantly get fresh tires. Poor grip causes many accidents, and I believe many drivers wait for the MOT before buying tyres. Runflats are great, but rim and tyre costs have kept them from taking off. I disagree with ditch finding cheaper tyre comment. They're fine for most purchasers but not for performance cars.

[johnmayerrr]

If a tyre abruptly deflates, the vehicle will be more controlled if it's a rear tyre, I believe. In terms of putting the best tyres on the back, I attempt to change all four at the same time. Assuming no damage necessitates replacement, this implies half the miles will be covered with the poorest rear tyres. I switched Mrs F's Pug's tyres front to back after 15,000 miles, assuming a 30K mile tyre life. There is just a centimetre difference, and as more miles is accumulated, the difference will diminish until they are equally worn when replacements are necessary.

This concludes some more 'normal crap'.