Replacing front tires

On Mon, 04 Sep 2006 23:31:55 -0500,
(Brent P) wrote:

>In article >, Bill Funk wrote:
>> On Sun, 03 Sep 2006 14:53:39 -0500,
>> (Brent P) wrote:
>>
>>>In article >, Bill Funk wrote:
>>>> On Sun, 3 Sep 2006 11:38:49 -0700, "Floyd Rogers"
> wrote:
>>>>
>>>>>> On a FWD car, the rears simply follow the front. They don't even
>>>>>> provide power, as they do on a RWD car.
>>>>>> There's no need to replace good tires on the rear.
>>>>>
>>>>>I think this should be clarified. When buying two tires (usually
>>>>>to replace the fronts which wear faster than the rears on a FWD
>>>>>car), the NEW tires should be placed on the REAR. The reason
>>>>>is that leaving the worn (but still legal) tires on the rear exposes
>>>>>the car to possibly severe oversteer conditions in wet when the
>>>>>rears hydroplane and the fronts (with new rubber) do not.
>>>
>>>> IMO:
>>>> Sounds good in theory, but in practice, my experience (very limited!)
>>>> is different.
>>>> In an F-250 (>6000lbs) with equal tires front & rear, the only
>>>> hydroplaning experience I've had occured; the front tiers were
>>>> hydroplaning. When I turned the sterering wheel, nothing happened. I
>>>> let up on the throttle, and a few seconds later, the truck turned.
>>>> It wasn't the rear tires (the less loaded tires) that floated, but the
>>>> fronts (with equal water on the road all around). When I let off the
>>>> throttle, the rear tires slowed the truck.
>>>> Just my (limited) experience.
>>>
>>>Your experience supports putting the good tires on the rear. This way
>>>instead of having the rear come around, one can just let up on the
>>>throttle and allow the vehicle to slow to where the fronts grip again.
>
>> My experience was that the front tires floated; why would this support
>> putting the better (not *good*; the rear tires were good) on the rear?
>> Then the fronts still would have floated.
>
>Because if the rears had 'floated' the ass end of your truck might have
>come around on you sending it into a spin....

Yes, if they'd floated.
They didn't.
>
>>>Even in a FWD car, there is friction to slow the car, just not engine
>>>braking from the rear.
>
>> This would mean you'd want the better tires on the front, to provide
>> engine braking. The rear tires on a FWD cars just follow along,
>> providing very little resistance (friction losses to speed). You can
>> see this by jacking up the car, and spinning the rear tires.
>
>No. You do not want the ass end of the car to come around under any
>circumstances.
>

True, but it's more likely the front tires will hydroplane than the
rears.
The *best* advice, then, is to replace your tires as soon as they show
any signs of wear.
But I seriously doubt anyone will want to do that.
We play the percentages.
--
Bill Funk
replace "g" with "a"

In article >, Bill Funk wrote:

>>> My experience was that the front tires floated; why would this support
>>> putting the better (not *good*; the rear tires were good) on the rear?
>>> Then the fronts still would have floated.
>>
>>Because if the rears had 'floated' the ass end of your truck might have
>>come around on you sending it into a spin....

> Yes, if they'd floated.
> They didn't.

If you had better tires on the front than the rear, the rear would float
and swing around.

>>>>Even in a FWD car, there is friction to slow the car, just not engine
>>>>braking from the rear.
>>
>>> This would mean you'd want the better tires on the front, to provide
>>> engine braking. The rear tires on a FWD cars just follow along,
>>> providing very little resistance (friction losses to speed). You can
>>> see this by jacking up the car, and spinning the rear tires.
>>
>>No. You do not want the ass end of the car to come around under any
>>circumstances.

> True, but it's more likely the front tires will hydroplane than the
> rears.

Actually it's less provided your vehicle has the engine in front.

> The *best* advice, then, is to replace your tires as soon as they show
> any signs of wear. But I seriously doubt anyone will want to do that.
> We play the percentages.

Yes, so put the new tires on the rear or risk having the assend go
down the road first.

Personally, I rotate tires and replace in sets of four.

On Tue, 05 Sep 2006 11:32:19 -0500,
(Brent P) wrote:

>In article >, Bill Funk wrote:
>
>>>> My experience was that the front tires floated; why would this support
>>>> putting the better (not *good*; the rear tires were good) on the rear?
>>>> Then the fronts still would have floated.
>>>
>>>Because if the rears had 'floated' the ass end of your truck might have
>>>come around on you sending it into a spin....
>
>> Yes, if they'd floated.
>> They didn't.
>
>If you had better tires on the front than the rear, the rear would float
>and swing around.

A completely unsupported assumption.
>
>>>>>Even in a FWD car, there is friction to slow the car, just not engine
>>>>>braking from the rear.
>>>
>>>> This would mean you'd want the better tires on the front, to provide
>>>> engine braking. The rear tires on a FWD cars just follow along,
>>>> providing very little resistance (friction losses to speed). You can
>>>> see this by jacking up the car, and spinning the rear tires.
>>>
>>>No. You do not want the ass end of the car to come around under any
>>>circumstances.
>
>> True, but it's more likely the front tires will hydroplane than the
>> rears.
>
>Actually it's less provided your vehicle has the engine in front.

The front tires hit the water with nothing to remove the water but the
tires themselves.
The rear tires hit the water aftert he front tires have cleared much
of it away, and what's there is disturbed, making hydroplaning much
less probable.
>
>> The *best* advice, then, is to replace your tires as soon as they show
>> any signs of wear. But I seriously doubt anyone will want to do that.
>> We play the percentages.
>
>Yes, so put the new tires on the rear or risk having the assend go
>down the road first.
>
>Personally, I rotate tires and replace in sets of four.
>
--
Bill Funk
replace "g" with "a"

In article >, Bill Funk wrote:

>>If you had better tires on the front than the rear, the rear would float
>>and swing around.

> A completely unsupported assumption.

Try basic physics and basic driving experience.

F=mu*N If you don't understand that, then there is no point in
continuing. Take a gripping front end and a sliding rear end and see what
happens.

You'd people would actually ask for cite for the statement the 'sky is
blue'.

>>Actually it's less provided your vehicle has the engine in front.

> The front tires hit the water with nothing to remove the water but the
> tires themselves.

> The rear tires hit the water aftert he front tires have cleared much
> of it away, and what's there is disturbed, making hydroplaning much
> less probable.

While there is some benefit to diving in the wipes... if the back looses
traction, the ass end comes around. If the front looses traction you keep
going forward.

Wipes or no, the rear can still break loose and come around. This is
highly undesirable in most regular driving. It can also be tricky
to control. Meanwhile, losing traction in front means letting off the
throttle.

"Bill Funk" > wrote
> (Brent P) wrote:

>>If you had better tires on the front than the rear, the rear would float
>>and swing around.
>
> A completely unsupported assumption.

Actually, COMPLETELY supported:
http://www.tirerack.com/tires/tirete....jsp?techid=52

FloydR

Floyd Rogers wrote:
> "Bill Funk" > wrote
> > (Brent P) wrote:
>
> >>If you had better tires on the front than the rear, the rear would float
> >>and swing around.
> >
> > A completely unsupported assumption.
>
> Actually, COMPLETELY supported:
> http://www.tirerack.com/tires/tirete....jsp?techid=52

I don't think constant radius wet skidpad testing transfers directly to
real world hydroplaning.

I suspect they weren't even sure the loss of the rear tires traction
was due to "hydroplaning", but jumped to that conclusion. Since the
rear wheels don't steer the loss of traction in hard cornering is more
likely attrbutable to simply exceeding the available lateral traction
of the rear tires on wet pavement, IMO.

The Tire Rack team includes not a single shred of data in their report;
not the vehicle, not the tires or their tread depths, not the velocity
at the point of "hydroplaning", absolutely nothing but assumption,
opinion and wags, AFAICT.

I find that report completely and utterly useless.
-----

- gpsman

gpsman wrote:
> Floyd Rogers wrote:
>
>>"Bill Funk" > wrote
>>
>>> (Brent P) wrote:
>>
>>>>If you had better tires on the front than the rear, the rear would float
>>>>and swing around.
>>>
>>>A completely unsupported assumption.
>>
>>Actually, COMPLETELY supported:
>>http://www.tirerack.com/tires/tirete....jsp?techid=52
>
>
> I don't think constant radius wet skidpad testing transfers directly to
> real world hydroplaning.
>
> I suspect they weren't even sure the loss of the rear tires traction
> was due to "hydroplaning", but jumped to that conclusion. Since the
> rear wheels don't steer the loss of traction in hard cornering is more
> likely attrbutable to simply exceeding the available lateral traction
> of the rear tires on wet pavement, IMO.
>
> The Tire Rack team includes not a single shred of data in their report;
> not the vehicle, not the tires or their tread depths, not the velocity
> at the point of "hydroplaning", absolutely nothing but assumption,
> opinion and wags, AFAICT.
>
> I find that report completely and utterly useless.
> -----
>
> - gpsman
>

So in exactly what way does that NOT translate to on-road safety?
Again, for most drivers, understeer is safer. When you put worn tires
on the rear, you get oversteer, in ALL conditions, even dry. Worn tires
not only don't shed water as well as new ones, the rubber itself gets
harder as the tire ages.

nate

--
replace "fly" with "com" to reply.
http://home.comcast.net/~njnagel

On Tue, 05 Sep 2006 14:46:45 -0500,
(Brent P) wrote:

>In article >, Bill Funk wrote:
>
>>>If you had better tires on the front than the rear, the rear would float
>>>and swing around.
>
>> A completely unsupported assumption.
>
>Try basic physics and basic driving experience.
>
>F=mu*N If you don't understand that, then there is no point in
>continuing. Take a gripping front end and a sliding rear end and see what
>happens.
>
>You'd people would actually ask for cite for the statement the 'sky is
>blue'.

It's unsupported because you're trying to use math to to show what can
happen (IF* the rear tires float; it's been said by myself and opthers
that it's more likely for the fronts to float, because the rears enter
water that's already been moved and disturbed by the front tires.
I understand what happens if the rears come loose; you seem to be
missing the situation that's being discussed.
>
>>>Actually it's less provided your vehicle has the engine in front.
>
>> The front tires hit the water with nothing to remove the water but the
>> tires themselves.
>
>> The rear tires hit the water aftert he front tires have cleared much
>> of it away, and what's there is disturbed, making hydroplaning much
>> less probable.
>
>While there is some benefit to diving in the wipes... if the back looses
>traction, the ass end comes around. If the front looses traction you keep
>going forward.

Which is what's being said. Glad to see you caught up.
>
>Wipes or no, the rear can still break loose and come around.

Of course it can. But it's much more likely the fronts will float
before the rears do, so the better tires should go on the front.
>This is
>highly undesirable in most regular driving. It can also be tricky
>to control. Meanwhile, losing traction in front means letting off the
>throttle.

>
--
Bill Funk
replace "g" with "a"

On Tue, 5 Sep 2006 13:26:53 -0700, "Floyd Rogers"
> wrote:

>"Bill Funk" > wrote
>> (Brent P) wrote:
>
>>>If you had better tires on the front than the rear, the rear would float
>>>and swing around.
>>
>> A completely unsupported assumption.
>
>Actually, COMPLETELY supported:
>http://www.tirerack.com/tires/tirete....jsp?techid=52
>
>FloydR
>

On a continuous curve pad.
Not many street situations are such; most driving is straight, where
the fronts will wipe the rear tire track.

--
Bill Funk
replace "g" with "a"

On Tue, 05 Sep 2006 19:23:03 -0400, Nate Nagel >
wrote:

>So in exactly what way does that NOT translate to on-road safety?
>Again, for most drivers, understeer is safer.

When the fronts float, there's NO steering; not just understeer.
>When you put worn tires
>on the rear, you get oversteer, in ALL conditions, even dry.

Hardly.
Most people never get anywhere near the limits of even worn tires.
>Worn tires
>not only don't shed water as well as new ones, the rubber itself gets
>harder as the tire ages.

--
Bill Funk
replace "g" with "a"