How to rotate dually tires
The manual for my 2016 Ram 3500 dually shows tire rotation only side to side. Specifically, switch the driver front and the passenger front tires, switch the outer rear tires driver to passenger, and ...
Forum Discussion
This has been an excellent thread on dually tire rotation.
A consideration that could use more emphasis is tire type and axle application.
Steer tires, with closed shoulders, relatively solid and unbroken ribs, and relatively straight circumferential grooves, are optimized for directional stability (less wandering) and cornering durability (closed shoulders).
Drive tires, with open shoulders, laterally divided lugs, zig zagging grooves, and staggered tread blocks, are optimized for traction. The open shoulders give the tire bite into soft terrain.
Even in 4WD duallies, the vast majority of the driving in both time and mileage is actually done in 2WD. More often than not, a 4WD dually will also have some type of limited slip rear differential, which reduces the need to shift into 4WD in many situations. So there is a good usage case for having drive tires on the rear drive axle, and steer tires on the front axle, even when the front axle is driven... because the front axle isn't usually driven that much.
In this case, a back to front tire rotation is not advised. The four drive tires on the back can be left alone, with just the two steer tires rotated side to side. The spare tire can be an all position tire, or a steer tire, and can be rotated in with the steer tires (if the truck has all steel wheels).
If the purpose of tire rotation is to "save money" by distributing uneven steer axle tire across all 6 or 7 operating tires under the guise of stretching the useful life of the tires... that may not actually be what happens.
If the alignment is "off" to the point of imposing irregular wear on the tires, and all 6 tires are given one or two tours of duty on the front axle, then all 6 tires will have to be replaced. This thread already covered that ground.
This thread also covered the fact that moving all 6 tires through a faulty aligned front axle simply masks the root problem... the alignment that is causing premature wear on the tires. At today's tire prices, it is cheaper to fix the root cause, rather than expose all the tires on the truck to the fault.
But what this thread did not yet emphasize enough is the operational benefit of having dedicated drive tires that are optimized for traction, and bear no steering duties at all; and having dedicated steer tires that are optimized for steering and directional control, and have only a limited and brief call to duty for drive traction.
By leaving the rear drive axle tires alone, and only rotating the fronts side to side, even in the most severe off alignment scenario, only 2 tires will need to be periodically replaced, rather than all 6.
I have a 4WD dually. A decade ago, I bought a set of four drive tires, mounted them on the rear axle, and never rotated them. Now 10 years and 40,000 miles later, the inner duals measure 14/32 tread depth, and the outer duals measure 13/32 tread depth.
A commercial tire tread depth gauge was used to determine these measurements, which were taken at the centermost lugs in the middle of each tire, with the tires and wheels dismounted from the truck and laying flat on the pavement.
When measuring tread depth at the outer shoulders of the tires they measured at 16/32nds, but that might be due to the beveled taper of the underlying casing.
Tire pressures were within 2 psi of each other (between 83-85, on load range G tires rated for up to 110 psi). One might assume that more wear on the outer duals implies that the inner duals must have been underinflated, but the inner dual had 85.
My thinking is that the outer duals are subject to slightly more wear due to being exposed to more turning and cornering scrub. The 1/32nd difference in wear observed occurred over a 40,000 mile period spanning 10 years of time, with dually pair couplets that were never rotated.
From this observation, I might try rotating the inner duals with the outer duals, by crossing the inside right to the outside left, and the outside right with the inside left, such that the tire rotational direction is maintained. This is with all steel wheels.
Obviously, at 10 years, these tires have aged out long before they have worn out. The goal of rotating tires is ultimately to save money, yet the savings realized by not rotating the rear dually pairs with the fronts (and not having to pay for dismounting and remounting tires on and off rims for those who run aluminum outers) likely leads to more money in the pocket, as well as a better driving experience from dedicated drive tires that would not be suitable as steer tires.
A consideration that could use more emphasis is tire type and axle application.
Steer tires, with closed shoulders, relatively solid and unbroken ribs, and relatively straight circumferential grooves, are optimized for directional stability (less wandering) and cornering durability (closed shoulders).
Drive tires, with open shoulders, laterally divided lugs, zig zagging grooves, and staggered tread blocks, are optimized for traction. The open shoulders give the tire bite into soft terrain.
Even in 4WD duallies, the vast majority of the driving in both time and mileage is actually done in 2WD. More often than not, a 4WD dually will also have some type of limited slip rear differential, which reduces the need to shift into 4WD in many situations. So there is a good usage case for having drive tires on the rear drive axle, and steer tires on the front axle, even when the front axle is driven... because the front axle isn't usually driven that much.
In this case, a back to front tire rotation is not advised. The four drive tires on the back can be left alone, with just the two steer tires rotated side to side. The spare tire can be an all position tire, or a steer tire, and can be rotated in with the steer tires (if the truck has all steel wheels).
If the purpose of tire rotation is to "save money" by distributing uneven steer axle tire across all 6 or 7 operating tires under the guise of stretching the useful life of the tires... that may not actually be what happens.
If the alignment is "off" to the point of imposing irregular wear on the tires, and all 6 tires are given one or two tours of duty on the front axle, then all 6 tires will have to be replaced. This thread already covered that ground.
This thread also covered the fact that moving all 6 tires through a faulty aligned front axle simply masks the root problem... the alignment that is causing premature wear on the tires. At today's tire prices, it is cheaper to fix the root cause, rather than expose all the tires on the truck to the fault.
But what this thread did not yet emphasize enough is the operational benefit of having dedicated drive tires that are optimized for traction, and bear no steering duties at all; and having dedicated steer tires that are optimized for steering and directional control, and have only a limited and brief call to duty for drive traction.
By leaving the rear drive axle tires alone, and only rotating the fronts side to side, even in the most severe off alignment scenario, only 2 tires will need to be periodically replaced, rather than all 6.
I have a 4WD dually. A decade ago, I bought a set of four drive tires, mounted them on the rear axle, and never rotated them. Now 10 years and 40,000 miles later, the inner duals measure 14/32 tread depth, and the outer duals measure 13/32 tread depth.
A commercial tire tread depth gauge was used to determine these measurements, which were taken at the centermost lugs in the middle of each tire, with the tires and wheels dismounted from the truck and laying flat on the pavement.
When measuring tread depth at the outer shoulders of the tires they measured at 16/32nds, but that might be due to the beveled taper of the underlying casing.
Tire pressures were within 2 psi of each other (between 83-85, on load range G tires rated for up to 110 psi). One might assume that more wear on the outer duals implies that the inner duals must have been underinflated, but the inner dual had 85.
My thinking is that the outer duals are subject to slightly more wear due to being exposed to more turning and cornering scrub. The 1/32nd difference in wear observed occurred over a 40,000 mile period spanning 10 years of time, with dually pair couplets that were never rotated.
From this observation, I might try rotating the inner duals with the outer duals, by crossing the inside right to the outside left, and the outside right with the inside left, such that the tire rotational direction is maintained. This is with all steel wheels.
Obviously, at 10 years, these tires have aged out long before they have worn out. The goal of rotating tires is ultimately to save money, yet the savings realized by not rotating the rear dually pairs with the fronts (and not having to pay for dismounting and remounting tires on and off rims for those who run aluminum outers) likely leads to more money in the pocket, as well as a better driving experience from dedicated drive tires that would not be suitable as steer tires.
