MT tires, same same, but different by 2mm

[94L C8E]

so, i have a '94, it has a Viscous Coupler, which i haven't removed - yet my research says i want it gone;
i just bought five 1/2 used BFG KO MT tires; at 1/5th the cost over new, jumped on it, didn't think..

catch: 3 are worn with 8mm tread left. 2 are worn with 6mm tread left.
i thought i'd try some math, but i'm hoping for more of a 80 series mechanical functioning discussion/ info/thx/please

it's maybe a 1/4 inch difference in rolling distance (circumference) on a 255/85/16 (assuming full 33 in diameter - minus wear*pi= 102.63 vs 102.88 inches [.25" difference]; 623 rev per mile.
so that's 155 inches difference in travel/ mile, or .246% different roll/mile
- is math even needed..?


is there anyone with real experience or knowledge who'd avoid this dilemma here?
or should i take them to be mounted without worry, all good. - planning to balance with CounterAct. (made in Canada)

who could comment on the 80 series' All-Time 4WD drive train, VC and the center diff and the front diff and rear diff and what happens with slightly differently worn tires at each axle?
- my research tells me, if i remove the VC and drive unlocked on paved roads, i'm fine.
but still, so many questions and IDK.
which axle should get the larger diameter, or better, MT tires?

now, what if my diff lock button gets activated, or the VC is seized?
or, what if i need to use the 8mm tread spare on the same axle as the 6mm tread tire, would that ruin my respective diff?

too many questions to list, i suppose i'm nervous, much obliged.
to 80 series tech.

 

[mmajsw]

I am sure that you do no have to worry about that small of a difference. Consider when one tire loses pressure. It can be a 1" (25mm) or more smaller in radius. Everything works fine over the miles and mile you did not notice the tire getting smaller.
Maybe you use a spare to replace a tire. Spare can be brand new or almost worn out. Again a difference in size. No problems noted when driving.
Turning a corner - outside tire can travel 2-3 feet or more in a very short distance. No binding or broken parts happens.
Slap those babies on enjoy them. The viscous coupling and the center diff will slip to accommodate any drive train binding that occurs during normal everyday driving and off road too.

 

[94L C8E]

Thanks for the reply,
And advice if I should put the better tires up front or to the rear?

 

[inkpot]

Put the two bigger tires on the front because the fronts travel farther due to the fact that they make a larger arc than the rears on turns.

 

[northernrighty]

that is going to caused some debate. My personal preference is to put the better tires up front, helps in braking and usually when your in trouble, you have to back out, and the extra traction will help when the front gets loaded up in reverse. being that your rig is awd, putting them on the back (as is "custom") has no real advantage in my mind?

 

[Funner]

Probably less of a variance than tires that aren't rotated frequently enough. Put them on and enjoy the good deal you found.
Also, no need to neuter you VC

 

[Douglas S]

This is a non-issue. Run them whichever way you like.

 

[LINUS]

That variance is negligible - most of us who do lazy rotations (me), have that on our 80's.

My driving scrubs more rubber from the front, start with the 2 bigger on that axle - inkpot gave a good "why" that I've never taken time to think of.

 

[BILT4ME]

Run them. 2mm will make no difference in your operation. The science tells everyone that you should always run the tries with the better tread in the REAR for better stability, whether it is FWD, RWD, AWD, or 4WD.

You can run your 2mm difference tires on the same axle with no difference as well. You got a good deal. Embrace it.

 

[Golgo13]

2mm is nothing. It is WAY inside the design tolerances. assuming 2mm difference, your circumference difference is 2pi*2mm=12.mm or 1/2".
That isn't even 1% of the total circumference. Don't over think it.

You could also put them both on one side and use it as a way to compensate for the crown in the road when driving...

 

[94L C8E]

sage advice everybody.
how much difference in tire wear is too much then?

and my only reason to think about putting the slightly better tires on the fronts, would've been to help maybe get the treads more evenly worn over time... hmm - u got me thinking.

Run them. 2mm will make no difference in your operation. The science tells everyone that you should always run the tries with the better tread in the REAR for better stability, whether it is FWD, RWD, AWD, or 4WD.

You can run your 2mm difference tires on the same axle with no difference as well. You got a good deal. Embrace it.

 

[Dave 2000]

Run them as you like. My preference is to have the best tyres at the front, this is where weight is transferred during heavy braking, they do the steering and the fronts . Re the comment the radius reduced by lower pressure, the radius may be reduces but the overall circumference remains the same. IMO if I take a tyre not even mounted on a rim and measure the circumference and it is 'X' then I decided to sit on the tread area crushing the tyre diameter and hence the radius then have someone measure the circumference it would be the same right, or am I missing something here? A tyre that may be worn yes the circumference is smaller but not related to the air pressure.

regards

Dave

 

[Qball]

If you like nascar put the better tires on the right side.

 

[Funner]

Run them as you like. My preference is to have the best tyres at the front, this is where weight is transferred during heavy braking, they do the steering and the fronts . Re the comment the radius reduced by lower pressure, the radius may be reduces but the overall circumference remains the same. IMO if I take a tyre not even mounted on a rim and measure the circumference and it is 'X' then I decided to sit on the tread area crushing the tyre diameter and hence the radius then have someone measure the circumference it would be the same right, or am I missing something here? A tyre that may be worn yes the circumference is smaller but not related to the air pressure.

regards

Dave

Yes, the tire will have the same circumference, greater tire pressure just reduces deformation so it will stand taller but won't be a larger circumference.