different axel width

enblethen wrote:
My big question remains in my head, why didn't they replace with the same axle as the one they removed.

X2!

However, I suspect one or several of the following reasons..

Miss measured, ordering the wrong length which most likely was not returnable.

Couldn't get the correct length quickly and bought the closest length they could find in stock.

Found one in the wrong length but it was deeply discounted pricing to the dealer.

While there are some common generic lengths, trailer frame manufacturers may have spec'd a certain odd length that is not typically stocked by an axle builder and is custom manufactured for that frame.. Those axles if you need to replace will have to be custom made by the axle builder and that takes time and may cost extra as a "one off" item.

Functionally, unless there's clearance issues, you won't experience any issues. Tandem axles scrub in tight turns and they'll scrub the same. Track width won't make a difference as it would in a driven axle.
JMO from what I know about trailers.
Did you tow it home? Any issues aside from appearance?

My big question remains in my head, why didn't they replace with the same axle as the one they removed.

As long as there's enough room for the tires to not rub anywhere, I doubt you'll even notice it, despite the naysayers.

It will tow down the road fine. On tire wear I cannot say.
The easy fix is to get one inch spacers for the narrow axle. Spacers are very common in the off-roading world where they put 2 inch or more wide spacers on the vehicle wheels so their big wide tires will fit inside the truck. Should be no problem on a trailer. You will need to know the bolt pattern. This will be something like 4.5 for many trailers. Look up how to measure, it is quite simple and everything can be done by you if you can change a wheel/flat.

I would not like it. Make dealer fix it. What did they do with the brakes? are they the same as other axle?
Tires would wear funny.
Cheap correction could be corrected with different wheels with different offset.

Buy skinner tires for that axle. Problem solved. J/K.

Should be no problem with 1" on each side.

Turning might be interesting...

In the end it won’t cause any issues. You’ll just have 2 wheels out a bit farther. I wouldn’t release a vehicle like that. If they can’t get the proper axle then I would have offered a deal to install a new same size second axle.
But in the end it will not cause an issue.