There is the rule of not pairing tires as a dual with a difference of no more than 5/32. Is there a rule for tires placed on one side of the axle versus the other? For simplicity, let’s take the example of a steer axle. On one side, the tire is at 5/32, and on the other, the tire is at 20/32. It seems like this may be acceptable, but perhaps it may cause inward tire wear on one tire and outer tire wear on the other. Now, the drive and trailer tandem axles are a more practical example than the steer axle. So, is there a general rule for this?
Steer axle yes, any other axles no. It doesn’t make it right IMHO, but at my company it’s not up to me.
I always replace both steers at the same time. No matter what. Drives I’m not as picky about. I try to match the same side. I generally replace a set at the same time because that’s the way they wear. But, the spider gear will compensate for whatever few 32nd’s difference there is. But steers will affect handling
I always did steers at the same time, I don’t have a specific reason for it. I don’t have any scientific proof but I would think a big difference from duals on one side to the other side would cause the differential to have to compensate for the size difference. I don’t know if that would be true or not, and I haven’t stayed at a Holiday Inn Express in a long time.
Main thing when mounting duals is matching height. I’ve seen big difference in brands despite being same size. A shorter tire will skip and get flat spots
Reputable tire shops won't put tires of too great a depth difference on the same axle. i.e., if 3 tires on the axle are at 6/32 they won't put anything greater than 10/32 or 12/32 with them.
What I am referring to is the tire height from one side of the axle versus the other side. I have only heard the 5/32 rule used for tires in a dual single operation and not on the entire axle.
This website says 4/32 between tires or sides of axle is max. Tire Wear | AcuTread Tire Service | Retreading Manufacturers
Back in the Bias tire days we were given a measuring stick that gave outside tire diameter and had to mount two tires together that were within 1/2 inch of each other for best wear. I haven't seen a device like that since radials took over. We were taught to use matching tread [had some funky trailer recaps] style for each side but no comparison to the other side of the axle. But bias tires had flats so often that a lot of drive and trailer duals were changed frequently. Flat tires used to be a REAL delay problem with Monday's being the worst. Chemical Leaman tracked tires [loved to brand new tires!] by branding numbers which were used on tire change cards describing position and on/off numbers that was stapled to the RO going to the office. Pre-deregulation staffing allowed such minute bean counting.
