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Mixed rims/tires

Printed From: Unofficial Allis
Category: Other Topics
Forum Name: Shops, Barns, Varmints, and Trucks
Forum Description: anything you want to talk about except politics
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=194692
Printed Date: 09 Sep 2025 at 2:01pm
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Topic: Mixed rims/tires
Posted By: Lars(wi)
Subject: Mixed rims/tires
Date Posted: 18 Apr 2023 at 3:16pm
Just noticed on my tire chart, 11R 22.5 is the exact same size as 285/75R 24.5 is it legal to mix rim sizes on duals, if the tire diameter match?

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I tried to follow the science, but it was not there. I then followed the money, and that’s where I found the science.



Replies:
Posted By: DMiller
Date Posted: 18 Apr 2023 at 3:46pm
NOT on commercial machines.  CAN place 22 tube type alongside 24.5 or 20 tube type alongside 22.5 is all,  Has to be similar construction as well.  Lo Pros are not same construct as normal size.


Posted By: Lars(wi)
Date Posted: 18 Apr 2023 at 3:49pm
Is it legal to have 11R 22.5 on one side of the axle, 285/75R 24.5 on the same axle on the other side of the truck?

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I tried to follow the science, but it was not there. I then followed the money, and that’s where I found the science.


Posted By: steve(ill)
Date Posted: 18 Apr 2023 at 4:06pm
why would you do that on a truck ?   Why would the rims be DIFFERENT to start with ?

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Like them all, but love the "B"s.


Posted By: Lars(wi)
Date Posted: 18 Apr 2023 at 4:10pm
Originally posted by steve(ill) steve(ill) wrote:

why would you do that on a truck ?   Why would the rims be DIFFERENT to start with ?

Have a lot of spares in the shop of the two different sizes. Trying to utilize what we have. Most will more likely be put on trailers.

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I tried to follow the science, but it was not there. I then followed the money, and that’s where I found the science.


Posted By: TomC
Date Posted: 18 Apr 2023 at 4:53pm
Lars,your asking for trouble putting miss matched tires on anything. Coming out of your shop you may have it straight but one blowout and a different shop you'll loose anything and more than you gained. I have seen these guys running up the highway running miss matched tires where one or more of the tires weren't even touching the ground.


Posted By: DMiller
Date Posted: 18 Apr 2023 at 5:01pm
If did ANYTHING, would set a match lot to an axle Full across, then they are not fighting each other, on a trailer even better.


Posted By: steve(ill)
Date Posted: 18 Apr 2023 at 5:18pm
yea... i could see one SET of 4 on one axle, and s SET of 4 on a DIFFERENT axle... that might be OK. ... but all should be the same on one axle.

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Like them all, but love the "B"s.


Posted By: ac fleet
Date Posted: 19 Apr 2023 at 10:27am
DONT DO IT!!!!!!!!!!!!!!!   you are settin yourself up for serious charges by DOT! THATS the exact thing they look for and usually the first! --- Trust me they do NOT miss that point!

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http://machinebuildersnetwork.com/


Posted By: DaveKamp
Date Posted: 21 Apr 2023 at 1:24am
+1 on what AC says.  DOT will NOT pass a mix-match.

One thing you certainly do NOT want to do, is have a mismatch between tires on an axle, and the NEXT thing you do not want to have, is a mismatch between front and rear axle in a both-driven circumstance.  The smaller diameter, even if miniscule, will fight the larger, and you'll wind up with very high tire heating as a result.  Even with an interaxle differential, you'll wind up with tire heating.

Mismatching tire width to rims is bad, and running mismatched tires in a dual is bad.  When you look on the tire sidewall, there's a load rating in SINGLE, and a load rating in DUAL.  The reason for the difference, is tire heating.  In a single application, equal airflow is available to cool the inside and outside of the tire and wheel.  In a dual, the space between the tires is significantly higher, because there's two wheels and tires who's heat is radiating towards eachother, rather than moving away, and the brake system is shrouded substantially by the second tire's presence.  The wheels serve as a heat-sink, but the outer does NOT conduct heat away as fast as the inner because the interface between the two wheels is inherently a thermal insulating barrier... the inner wheel face gets hotter.  The end result, is that the running temperature of duals is HIGHER than singles, so the tire's capacity must be de-rated to accomodate the tire temperature.

This is also why SOME tires have TWO pressure ratings... one for single, and one for dual.  MOST manufacturers won't, they'll just use the lower of the two, but SOME do.

This is also why there are some tires rated for STEER position, while others are rated for DRIVE POSITION ONLY... the drive tire structure is optimized for a particular load and operating temperature profile under compression, thrust, and braking, while the steer tire's structure is optimized for greatest durability under steering and braking loads.  The steer position tread design is usually optimized for handling stability.

And please... NEVER mount them with fire.


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Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest.



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