Running oversized spare for 200mi OK or dangerous?

[Summit]

Running oversized spare for 500mi OK or dangerous?

A snow tire 30.5" (left rear) completely exploded itself and I put on the spare 31.6" summer. (After wear, probably 30.4 vs 31.4 so 3.1%-3.5% difference)

The replacement snow is coming. The tires are new enough that the tire dealer said I didn't need to replace all 4. But the tire dealer freaked out about me driving 3 30.5" and 1 31.6". I've already driven 250mi in AWD with zero issue in this configuration.

Is it safe WITH RESPECT TO BRAKES/DRIVE TRAIN DAMAGE (I understand traction differences) to drive another 250mi until the replacement snow comes in? Or do I have to take off the 3 remaining snows, put on my summers, and then switch them all back again?

 

[eddiebx]

A snow tire 30.5" (left rear) completely exploded itself and I put on the spare 31.6" summer. (After wear, probably 30.4 vs 31.4 so 3.1%-3.5% difference)

The replacement snow is coming. The tires are new enough that the tire dealer said I didn't need to replace all 4. But the tire dealer freaked out about me driving 3 30.5" and 1 31.6". I've already driven 250mi in AWD with zero issue in this configuration.

Is it safe WITH RESPECT TO BRAKES/DRIVE TRAIN DAMAGE (I understand traction differences) to drive another 250mi until the replacement snow comes in? Or do I have to take off the 3 remaining snows, put on my summers, and then switch them all back again?

It's probably not the best idea to be doing this with AWD because one wheel will be turn faster than the other three and it might screw with the center differential (overworking it). However, while there is most likely no immediate damage, it would be best to stop driving like that for now until you can get a matched set of tires on there.

Just for future reference, if you plan to run smaller tires seasonally, maybe it would be best to get a 5th spare for each set of tires so you don't get caught in this type or predicament again

 

[nevada]

you can run a little less air in the taller tire, to help bring the rolling diameter down closer to the others.

what environment are you driving in it? is the ground covered with snow/ice?
if yes, then it should be fine, much better than if dry pavement.

 

[Summit]

mix of snow and ice and pavement

 

[having fun]

Just put it on the rear and drop some air pressure, but not to much to create sway.

 

[fourwd1]

Just put it on the rear and drop some air pressure, but not to much to create sway.

^^ what he said

 

[Summit]

Just put it on the rear and drop some air pressure, but not to much to create sway.

Did that worked well so far

 

[having fun]

Did that worked well so far

I haven't had to do this. I have off road tires and street tires also, but keep a spare for both, different sizes also.

The comment is just common sense to do, as different size tires on the front can pull differently and make the abs,vsc work strange.

 

[KidVermicious]

Am I the first guy that's going to say this is a bad idea? I don't know anything about the AWD or what damage might be done there, but having two tires with vastly different traction abilities on the same axle is a bad bad bad idea. Having different tires on a drive axle is worse. Especially on ice. You should at least have the tire shop mount up one more summer tire, and put them both on the rear axle.

Do you really need dedicated winter tires this late? I'd probably just slap the summer tires on and forget it. You do have 4wd, after all.

 

[541joseph]

Am I the first guy that's going to say this is a bad idea? I don't know anything about the AWD or what damage might be done there, but having two tires with vastly different traction abilities on the same axle is a bad bad bad idea. Having different tires on a drive axle is worse. Especially on ice. You should at least have the tire shop mount up one more summer tire, and put them both on the rear axle.

Do you really need dedicated winter tires this late? I'd probably just slap the summer tires on and forget it. You do have 4wd, after all.

That would be worse because the difference from front to rear would be greater and therefore overheat the tcase

Op the biggest issue is you could severely over heat your tcase