Different sized wheels and tires on car. Dangerous/Harmful?

[alansupra94]

I am asking because my HRE wheel blew out the tire today (it was already bad and will be replaced tomorrow) and was wondering the safety of running a spare wheel and tire that is slightly larger/small than what is there. Can any damage really be done? I NEEDED to get to work or I wouldn't have driven. The drive is only about a 25min drive and would be off the car tomorrow but I am just curious.

I noticed with running this spare there is a intermitted vibration that comes and goes (about a 2 second interval). I figured this is related to the over/undersized spare. I guess it is just good to know so I can look for a better spare.

Thanks,
Alan

 

[Muskrat]

Because the wheels need to turn at different speeds, it induced more stresses into the mechanical drive system. While it's wont really do any damage for a short drive, don't drive on it for an extended period. Many manufacturer's supply an undersized spare with their vehicle, but they caution to only use it to get to a repair facility. Sometimes they give a maximum range you should drive.

While I think you'll be ok for your drive to work, I would suggest getting a new tire on your correctly sized rim ASAP.

 

[alansupra94]

Yeah I really just need to get home. It is about 25 miles at most.

Thanks for the help dude.