Question about AMT White-Freightliner COE Wheels and Tires

[53_Sedandelivery]

Hi-yo! I've heard conflicting information about AMT's White-Freightliner COE wheels and tires.

1. From what I have gathered from various sources, the 1:1 rig wore 24.5" wheels, and the wheels in the kit are close to that size. This supposedly applies to this kit, the Road Boss and White conventional, and possibly the Kenworth K-series cabover. As for the Kenworth W900 and Peterbilt conventionals, they are supposed to have 22.5" rims but are actually 20" rims. Can anyone confirm?

2. The rims in my Freightliner COE kit appear to be of the "split rim" type.  Not an expert on this older wheel other than they used "tubes". Is this as good as a split rim gets? Need a set for a Movin' On KW.

There's a seller on Ebay with directional rims using a Freightliner emblem shaped hole, but they are listed as 22.5" rims. Not sure they would work prototypically or actually on this COE kit. My guess is 1/24 scale directionals from M&R wheels will be the best prototypical wheels for this truck?

[vincen47]

On 2/11/2025 at 12:11 PM, 53_Sedandelivery said:

Hi-yo! I've heard conflicting information about AMT's White-Freightliner COE wheels and tires.

1. From what I have gathered from various sources, the 1:1 rig wore 24.5" wheels, and the wheels in the kit are close to that size. This supposedly applies to this kit, the Road Boss and White conventional, and possibly the Kenworth K-series cabover. As for the Kenworth W900 and Peterbilt conventionals, they are supposed to have 22.5" rims but are actually 20" rims. Can anyone confirm?

2. The rims in my Freightliner COE kit appear to be of the "split rim" type.  Not an expert on this older wheel other than they used "tubes". Is this as good as a split rim gets? Need a set for a Movin' On KW.

There's a seller on Ebay with directional rims using a Freightliner emblem shaped hole, but they are listed as 22.5" rims. Not sure they would work prototypically or actually on this COE kit. My guess is 1/24 scale directionals from M&R wheels will be the best prototypical wheels for this truck?

I replied over on the MTB forum, but I wasn’t able to provide a lot of specific info you’re after. Here’s a link to a thread on this forum that might be of use:

I understand the frustration. So much inconstancy in terms of labeling and scale accuracy amongst truck wheels and tires. Not to mention, 1:1 changes over time, like split rims and spokes to forged aluminum discs.

[Aaronw]

The way measurements are taken on a rim for tube tires is different than tubeless. 22.5" is a tubeless size, 20" is tube style but they are essentially the same size. The main difference will be rim style, tubeless use a single piece wheel, tube tires a multi-piece wheel.

Tubeless tires / rims were available for semis by the 1950s, but tube tires remained popular well into the 70s. Anytime between the mid 1950s and the 1980s either would have been an option.

Based on the real world growing up in the 70s and early 80s my parents would often stop at trucks stops when we went camping to buy a couple of used truck tubes to float around in lakes and rivers. Pretty much any truck stop had them available. By the time I graduated high school in the mid 80s, it was much harder to find them.

On the tubeless side I have a 1958 Dodge W500 (2 ton truck) fire engine with original 22.5" tubeless wheels.    

 

Not sure what is in the kits, 20" would have probably been more common in the 60s and 70s, but either would be correct until the late 1980s when a 20" tube wheel would have been an unusual choice. They still make 20" tube tires / wheels for special applications. 

Edited February 13 by Aaronw

[vincen47]

8 hours ago, Aaronw said:

The way measurements are taken on a rim for tube tires is different than tubeless. 22.5" is a tubeless size, 20" is tube style but they are essentially the same size. The main difference will be rim style, tubeless use a single piece wheel, tube tires a multi-piece wheel.

Tubeless tires / rims were available for semis by the 1950s, but tube tires remained popular well into the 70s. Anytime between the mid 1950s and the 1980s either would have been an option.

Based on the real world growing up in the 70s and early 80s my parents would often stop at trucks stops when we went camping to buy a couple of used truck tubes to float around in lakes and rivers. Pretty much any truck stop had them available. By the time I graduated high school in the mid 80s, it was much harder to find them.

On the tubeless side I have a 1958 Dodge W500 (2 ton truck) fire engine with original 22.5" tubeless wheels.    

 

Not sure what is in the kits, 20" would have probably been more common in the 60s and 70s, but either would be correct until the late 1980s when a 20" tube wheel would have been an unusual choice. They still make 20" tube tires / wheels for special applications. 

Thanks for the great info. That clears up some confusion on my part. I had just measure the wheels from AMT’s T600 and they scale out to just about 22.5” in 1/25. I wasn’t planning on using the kit wheels, but I thought “how the heck do they call these 20” wheels? AMT was way off.” Now I know why and that AMT wasn’t in the wrong.

[Aaronw]

1 hour ago, vincen47 said:

Thanks for the great info. That clears up some confusion on my part. I had just measure the wheels from AMT’s T600 and they scale out to just about 22.5” in 1/25. I wasn’t planning on using the kit wheels, but I thought “how the heck do they call these 20” wheels? AMT was way off.” Now I know why and that AMT wasn’t in the wrong.

 

It is kind of confusing, but has to do with where the measurements are taken. A wheel for a 10-20 tube tire and a wheel for an 11-22.5 tubeless tire are considered to be the same size when people want to swap to a modern wheel.

Tube tire rims are basically flat across the center, while tubeless have sort of a funky V shape. Where the tire actually meets the rim is larger on a tubeless, but the clearance in the wheel center and overall diameter of tire are close enough not to matter. I guess the measurement is at the point where the tire seats against the wheel, not the exposed rim. 

This issue comes up frequently on vintage truck sites when people are looking to replace the antiquated tube wheels with tubeless rims. 

[DRIPTROIT 71]

On 2/11/2025 at 12:11 PM, 53_Sedandelivery said:

Hi-yo! I've heard conflicting information about AMT's White-Freightliner COE wheels and tires.

1. From what I have gathered from various sources, the 1:1 rig wore 24.5" wheels, and the wheels in the kit are close to that size. This supposedly applies to this kit, the Road Boss and White conventional, and possibly the Kenworth K-series cabover. As for the Kenworth W900 and Peterbilt conventionals, they are supposed to have 22.5" rims but are actually 20" rims. Can anyone confirm?

2. The rims in my Freightliner COE kit appear to be of the "split rim" type.  Not an expert on this older wheel other than they used "tubes". Is this as good as a split rim gets? Need a set for a Movin' On KW.

There's a seller on Ebay with directional rims using a Freightliner emblem shaped hole, but they are listed as 22.5" rims. Not sure they would work prototypically or actually on this COE kit. My guess is 1/24 scale directionals from M&R wheels will be the best prototypical wheels for this truck?

Just to add a little to what has already been said. Wheel diameter is measured where the bead of the tire sits on the rim. Split rims have a taller lip around the edge than tubeless rims which sometimes makes them appear larger than they are sometimes. As already said, tubeless rims are generally 22.5” or 24.5” and sometimes 19.5” on lighter duty and some lift axles. Split rims, which ran tubes were usually 20”, 22” or 24”. 20” split rims and 22.5 tubeless rims fit the same spokes on spoke type wheels. As already stated both were available and even popular from the 70s - the 90s, at least around here. Most AMT kits are modeled after split rims including the Freightliner. 

[Force]

On 2/11/2025 at 6:11 PM, 53_Sedandelivery said:

Hi-yo! I've heard conflicting information about AMT's White-Freightliner COE wheels and tires.

1. From what I have gathered from various sources, the 1:1 rig wore 24.5" wheels, and the wheels in the kit are close to that size. This supposedly applies to this kit, the Road Boss and White conventional, and possibly the Kenworth K-series cabover. As for the Kenworth W900 and Peterbilt conventionals, they are supposed to have 22.5" rims but are actually 20" rims. Can anyone confirm?

2. The rims in my Freightliner COE kit appear to be of the "split rim" type.  Not an expert on this older wheel other than they used "tubes". Is this as good as a split rim gets? Need a set for a Movin' On KW.

There's a seller on Ebay with directional rims using a Freightliner emblem shaped hole, but they are listed as 22.5" rims. Not sure they would work prototypically or actually on this COE kit. My guess is 1/24 scale directionals from M&R wheels will be the best prototypical wheels for this truck?

Back in the day when most ran on bias ply inner tube tires the rim sizes was 20 or 22 inches for the wheels, and popular tire sizes were 10.00-20, 11.00-20 for the 20 inch rims and 10.00-22 or 11.00-22 for the 22 inch rims, these rims are two or three piece split ring/lock ring rims where you take off a separate lock ring and outside ring to mount the tire and the rim itself is flat from outside to inside.
The more modern era wheels for tubeless tires are 22.5 and 24.5 inches and they are one piece rims with a "ditch" in the middle to mount the tires, today almost all highway trucks has 22.5 inch rims and earlier 24.5 inch rims were popular, but today almost all highway trucks have 22.5 inch rims.
Examples of tire sizes are 11.00-22.5, 12.00-22.5, and the same for 24.5, but lately many truck tires comes in metric widths like 385 and so forth.
Most of the US truck models available to us from AMT has split ring/lock ring wheels and the White-Freightliner and a few others like the Autocar, the Diamond REO and White Road Boss has 22 inch rims and the others like the Kenworth W925-K123, the Peterbilt 359-352, the GMC General and Chevy Bison, the GMC Astro and Chevy Titan 90 and the trailers has the smaller 20 inch rims, one exception was the Kenworth K100 Aerodyne wich have a kind of tubeless wheel but the rears has no ditch in the middle and it has the 11.00-22 inch tires.
The Ertl truck and trailer kits had a slightly larger outside diameter tire than the AMT kits, their 11.00-20 had a larger outside diameter and was also slightly wider, these tires also found it's way into some AMT truck kits after the AMT/ERTL merge, among them the Kenworth T600A and a few others.