I don’t think police car ramming and tractor use would be applicable during normal driving conditions.
If a police cruiser rams a quarter panel hard enough the car is going sideways no matter if the tires are worn out or brand new.
Note that a lot of time police ramming techniques involve a bit of momentum with the rammee being shoved while at speed or during a turn.
The OP asked for opinions and I gave them mine. I just do not want to wrestle the steering wheel with both hands while trying to keep 2 hydroplaning worn tires in the same lane the steering wheel is in.
I agree with mountainbike and others, as far as getting the best on the rear, and on using 4 snows on a FWD vehicle. I had 2 snows on the front of my 96 Cirrus, and A/S on the rear. I was on an entrance ramp to a super highway in Reading, PA, and there was an inch of wet snow on the ramp,
but the highway lanes themselves were merely wet (like a rainy highway). As the front tires contacted the wet highway, I had to accelerate. At that moment the rears were on the snow on the entrance ramp. I did a 180 and smashed into the center guardrail. Any truck that might have been coming up in the left lane would have sent me to the Promised Land.
You don’t really lose much $ using 4 snows in the winter, since you’re saving the other 4 A/S. Sure, where there’s not much snow, there’s no need to buy snows at all. Just keep 4 A/S with equal tread on them, or best on rear.
Well, I have to agree with OK on this one. Hydroplaning is a big problem here in Texas, too, now that it’s raining again and I like new ones on the front. If the shop won’t do it, I’ll change 'em when I get home. My biggest problem is accelerating from a stop at a wet intersection when running with worn tires. The new ones on the front is favored for that reason, too.
For me , it’s a difference in traction which includes more than tread depth. A significant difference in air pressure would be a problem as well. Generally, If I were to consider new tires on front, the rear tires would have to be less than half worn and within perhaps your 1/32 is reasonable after all, if you rotate, the fronts will always be a little better.
But…ALL vehicles generally maintain better control with the traction bias on the rear. Please consider all standard airplane design, all standard water craft, all have significantly more friction area toward the rear. As well as the entire fish and bird population. No craft can turn from the front unless it has friction from the rear to turn against. A car goes out of control with friction lost at the rear, because the turning wheels on the front generally initiate the leverage.
You miss the point, all vehicles perform with better control with friction equal, or bias to the rear. The police (I was one and that’s how it was explained to me by state police during pursuit discussion and demonstration classes), know that loss of traction in the rear means loss of control that is much less recoverable. It’s not a matter of deciding who you agree with, it’s a matter of refuting physics or not. Equal traction or bias to the rear is safest.
If you have to put the best tires on the front of FWD because you can’t even accelerate in the rain, you have a bigger problem with the other tires in rain that you’re in denial with. Whether or not you can turn, depends as much in slippery conditions in having enough traction on the rear for the front end to lever against as it does traction on the front. It’s not an opinion. If you have the worse traction on front, you will tend to under-steer more, but have much less chance of spinning out and/or loosing control
A couple of years ago I drove my daughter’s Mitsubishi on rain slick highways with 2 new tires on the back and tires with about 30% of the tread left on the front. That car was all over the highway at 60 MPH.
Fast forward a few months with 2 new tires on the front and it holds the road fine at 70 MPH on rain slick roadways. (the same stretch of highway too)
If you’re using the argument that one can’t accelerate in the rain on a FWD due to worn tires then the same argument could be used about a RWD vehicle.
If one wants maximum traction on dry pavement then 4 drag slicks will work fine. (as long as you’re not caught in a downpour)
I’ve got a pair of NASCAR tires (one from Dale Jr.s car and one from Bobby LaBonte) and while they’re not used (much) on the public roadways, they stick to the pavement like glue; and without a bit of tread. Technically, they’re as worn out as can be.
The basic principle in engineering is that for a definitive statement, there has to be an abrupt change or an inflection point - an obviously there isn’t one here.
Michelin did a study and their ride evaluators could not detect the difference at 1/32nd of an inch tread depth, and could barely at 2/32nds. So the rule of thumb is that 2/32nds is the point.
It is arbitrary? Yes, but at least it is based on some facts.
I guess we can agree you were referring to racing tires knowing they really have little to go with this discussion because the are not used in the rain/snow for the very reasons you stated. The will have little traction in anything but dry pavement conditions.
That your car was difficult to control with poor tires on front in rain is obvious. That you did manage to control it bears out that you had the better tires on back. Did you even have matched tread patterns of the two sets of tires and were the same models when this occurred ? That may have a greater influence.
That you later say that when the new tires were on front and proves your point says nothing about the condition of those on the rear at the time and their tread pattern match. The fact remains that “all” tires should have adequate tread for the conditions and with a significant difference, maybe now >2/32 inch which is always problematic, the better ones on the rear give better control…we never said if bald tires are on the front, you’re safe.
If you follow NASCAR racing as you seem to do, get on a web site with your favorite driver that allow questions and propose this under discussion question given by OP.
Then report back your findings in another post…they’re the experts. And you feel good about mounting tires contradictory to advice given by all tire manufacturers, distributors and garages ?
Thanks for the research, that makes me feel better about using that range for rotation, as without some difference, it would be very difficult to rationalize rotating tires at all. But there are so many variables relative to the safety of a tires, as the inflection point of change can vary with actual tread depth and pattern and we assume that Michelin was obviously making this statement relative to all four tires being the same model. Hence my comment that matching tires may be of equal or more importance than tread depth.
Put the new ones on the rear, but shop around for some better ones for the front. You can often find pretty good used tires for half or less of new tire price!
The way I look at it is that if someone is sliding on dry pavement there’s likely a driving habit problem; not a tire wear problem.
As to the example given, all of the tires on that car were the same brand and model. (Goodyears)
And what is the purpose of tire tread anyway? In a nutshell, it’s to displace water.
The OP asks for opinions and I gave mine. I simply prefer that the new front tires clear a path through water for worn rear tires (worn not meaning bald either) and dry pavement will take care of itself.
As to advice given by tire makers, etc., yes I not only feel good about what I’ve always done and my opinion on the subject but feel that way without any hesitation at all.
While I’ve slowed the mileage over the last number of years, I used to commute back and forth 160 miles a day to work. (190 miles when a certain highway always flooded during rainstorms) so you can see I put a lot of mileage on a vehicle along with going through a lot of rubber.
What I’ve recommended has always served me well and never ever been a problem.
Interesting point, however putting worn ones on front will lead to easier hydroplaning and less false sense of security. Basically a driver will slow down in rain when losing traction at a lower speed with the recommended setup.
Whitey, I can’t say we get a LOT of snow here in midwest Missouri, however we, like everyone in the the country, are getting plenty this year. But for your info, I put 2 new tires on the back of my van a couple of months ago because the back ones were bad, and then 2 new ones on the front later.
