Backspace

[Steve Demeter]

I just got a spare wheel and tire from E Trailer to supplement my existing one. Now I have two.

The question is:

The backspace on my existing wheels is 5". The backspace on the new "supplemental" spare is 4".

all other dimensions are the same.

the question is should I expect any funny behavior from the trailer if I need to use that wheel, given that the track on the axle it is on will be an inch wider than the other one/

[DaveW]

Unless the tire rubs on a fender because of the different backspace, I wouldn't expect to feel much if any difference. It might put more strain on the bearings if you use it with heavy loads. It will stick out more, so more likely to run into curbs or off the edge of the road.

[Jim Edmonds]

Hmmm . . with a single axle trailer I would expect the trailer to pull slightly off center putting both trailer tires in continual scrub. Normally the tires would pull symmetrically to the hitch-axle perpendicular. You might not notice the scrub when driving, but the tires will know.

If you are just going a short distance to replace the other two tires I wouldn't worry about it. If you are heavily loaded and need to go several hundred miles at highway speeds in the summer, I would worry.

We've all run different size trailer tires when we've had to. I'd prefer to send it back if you can and get the correct wheel. It might not make a difference but why find out?

Jim

[DaveW]

It's unlikely that just having one tire further out will cause scrub. The 2 tires need to be not parallel to each other to cause that.

OTOH, as Jim says, if possible, I'd try to get it replaced with one with the correct backspace to eliminate all possible issues.

[Steve Demeter]

Thanks for the wise words gentlemen. About what I thought.

Since it is an auxiliary spare, I think I will save the cost of returning it and use it only when I lose two tires in one trip. Have had that happen and was fortunate enough to get the spare that I carried without a wheel mounted at the track before the second one expired on the way home.

2 of the tires on the ground are 2014. 2 are 2017.

[DaveW]

Did you check to assure that a tire mounted on that wheel will clear the fenders?

[Steve Demeter]

Yep. Wheel came with tire and it clears the fender quite nicely. Actually the BS I was measuring was from tire sidewall to mounting surface. not to wheel edge. Clearance is tight on inside not on fender side.