NGC - tire rotation pattern

[brider]

For a 4WD, or more specifically, an All-wheel-drive vehicle where the front and rear axles are being driven at the same time from a transfer case, I've read that the preferred rotation pattern is same-side rear-to-front for the rear tires, Rfront to Lrear, Lfront to Rrear for the fronts.

Can anyone explain this logic? Why would a pair of tires swap spots but remain in the same rotation direction (the rears), while the other pair are reversed in rotation direction (the fronts)?

Why wouldn't all 4 swap in a cross-pattern, so that all 4 change rotation direction?

My case is my '93 Range Rover that my kid now drives. I put brand new BFG Commercial Traction TA tires on it (an awesome tire), and they were whisper-quiet for the first few thou miles. I drove it today, though, after the kid has put another 5-6 thou on it, and they're getting  buzzy and lumpy at low speeds, and kinda noisy on the highway. Time for their first rotation.

[RinkRat II]

     As per Goodrich, those should be rotated in an X pattern front to rear and not be kept on the same side for all wheel drive. Every Mfg has their own rotation pattern dictated by the way the carcass is built and materials used, aramid, polyester etc. Tread patterns and load range plays into it also.  As an aside, if your getting noticeable wear at this mileage, rotate them a little sooner and have it aligned. My$.02

        Paul B

[brider]

Many thanks, Paul.

[Zoom Zoom]

     As per Goodrich, those should be rotated in an X pattern front to rear and not be kept on the same side for all wheel drive. Every Mfg has their own rotation pattern dictated by the way the carcass is built and materials used, aramid, polyester etc. Tread patterns and load range plays into it also.  As an aside, if your getting noticeable wear at this mileage, rotate them a little sooner and have it aligned. My$.02

        Paul B

Question, and I really am asking. Not trying to be an a**?

Since it is a given that tire pressure is related to the particular vehicle, with the objective to get even wear across the width of the tread among other things, it's accepted that one use the car manufacturers recommendation since that would vary with the weight over the tires.

Now with regard to rotation, is the tire manufacturer recommendation better than what the car manufacturer suggests?

For instance, Subaru says to cross my rears when moving them to the front, and move the fronts straight to the back. That would put the next tire rotation, (the backs moving to the front), on the opposite front corner from where they were before. That sort of makes sense if you consider that always using an X pattern will always move RF to LR, LF to RR, and back again. Never getting either pair to a different corner. This is not taking into account different suspension setups and their related geometry, which I realize might sound like a bigger deal that what it really is.

But it does beg the question of weather to follow the tire or car manufacturer in this regard.

John Henry   

[RinkRat II]

 A couple of things on this ZZ, If you replace the factory tires with the exact same tire you can follow the car Mfgr. reccomendation for rotation and pressure and be fine. Most people don't and then you need to look to the tire mfg. reccommendation. Front wheel drive, rearwheel drive, all wheel drive and dually's all use different rotation patterns due to the differences in drive dynamics.Loading the tires as in cornering, acceleration etc. is very different between the awd fwd and rwd and rotation patterns help longevity as best they can. Pressure is a compromise reccomendation and really you should use the 10% rule and a tread depth gauge, however almost nobody does this so we get "recommended" stats. As far as your Subi goes, with the drive system they use, their testing supports their reccomendation for tire longevity.

    Paul B

[ozarquebus]

Of course in the old days with bias tires and rear wheel drive it was always the same: " X ", plus use the spare in rotation.

Then they came up with the "H" rotation with radials under the premis that tires take a "set" and steering may be affected.
 I have old tires which do seem to pull one way or the other, depending how they are oriented, so there may be something to that.

I have also heard it recommended to only rotate fronts on front and rears on rear.

As far a wear goes, I think there are several variables at play which out rank tire rotation in importance.

Tire inflation: No Brainer 1.In my experience, the recommended inflation from  car or tire mfg, will produce uneven wear greatest at edges of tires.
I follow advice of Hunter S. Thompson noted car guru(RIP), and even though 90lbs is too extreme, I have to put about 50 lbs in my Subaru to wear evenly across tire. In all my years, I do not think I have ever worn the tread out in the center of a tire. Manufacturers seem to recommend what I would consider to be under-inflation in order to give a more satisfactory ride and possibly better grip.


No Brainer 2. Front end Alignment must be very good.

So this is my philosophy on car tires:

Interpret mfg recommendations with liberal grain of salt.

If alignment and inflation is perfect, then worry about rotation.

If your tire wears on one edge of the tire, go X.
If it is even, it doesn't matter how you rotate.
You will probably ruin a tire by hitting something along the way and throw your strategy out the window anyway.

[brider]

I follow advice of Hunter S. Thompson noted car guru(RIP), and even though 90lbs is too extreme, I have to put about 50 lbs in my Subaru to wear evenly across tire.

If you've been inflating your Suby to 50 psi and haven't suffered a blowout yet, I'd be very curious to see what the sidewall max pressure rating is. I assume they're P-rated tires, and 50 seems waaaay too high for those tires. Be careful not to exceed the sidewall max pressure...there's margin of safety built into that number, but still...

[ozarquebus]

brider,
It may seem waaay too high, but it isnt.
50 lbs is within allowable pressure limits for the tire as per the lord high glorious, omnipotent and all-knowing manufacturer. They even printed it on the sidewall.
  Yokohama Geolander
P225/60R17 98H  51Lbs Max Pressure