Kidorry   188 #1 Posted March 20, 2019 Is it safe to have three 16 inch wheels and one 15 inch wheel on a car at the same time. Personally I think it is unsafe, but, I would like to know for sure. Cheers. Share this post Link to post Share on other sites Share this content via...
rudds1   101 #2 Posted March 20, 2019 It’s only like using one of those space saver spare wheels if your doing this temporarily Share this post Link to post Share on other sites Share this content via...
Cyclone   10 #3 Posted March 20, 2019 In theory you could alter the tyre profile so that the rolling circumference was the same. But fundamentally it's unsafe. Share this post Link to post Share on other sites Share this content via...
alchresearch   191 #4 Posted March 20, 2019 1 hour ago, rudds1 said: It’s only like using one of those space saver spare wheels if your doing this temporarily But aren't they the same size, just thinner? Share this post Link to post Share on other sites Share this content via...
Cyclone   10 #5 Posted March 20, 2019 3 minutes ago, alchresearch said: But aren't they the same size, just thinner? Yes, they aren't a different size. Share this post Link to post Share on other sites Share this content via...
trants   10 #6 Posted March 20, 2019 You would be fine on a temporary basis as long as the rolling circumference is not miles out as already mentioned . type in , tyre calculator , in google and you will be able to compare . My car when new came with 215/40/17 wheels and tyres , the manufacturer spare in the boot was 185/60/15 .  Just to complicate matters your car would not pass an MOT with different wheel sizes on the same axle. Share this post Link to post Share on other sites Share this content via...
woodview   10 #7 Posted March 20, 2019 It'll 'work' , so long as it fits in the band of allowable sizes as described above. The larger wheels would have lower profile tyres than the smaller wheel. It's a breakdown or emergency solution though, you need to get it sorted properly straight away. Share this post Link to post Share on other sites Share this content via...
El Cid   177 #8 Posted March 20, 2019 (edited) 2 hours ago, Kidorry said: Is it safe to have three 16 inch wheels and one 15 inch wheel on a car at the same time. Personally I think it is unsafe, but, I would like to know for sure. Cheers. I bought a car like that once, lol, it is not road worthy and should not pass an MOT. Or maybe this is what the manufacturer recommends, and it's not on the same axel? Edited March 20, 2019 by El Cid Share this post Link to post Share on other sites Share this content via...
smithy266 Â Â 21 #9 Posted March 20, 2019 (edited) If you use it on the driven axle, the diff will think you are going around a loooong corner and may get warm, and if it is on the steering, may pull to one side. Why do you want/need to do this? Edited March 20, 2019 by smithy266 Share this post Link to post Share on other sites Share this content via...
Kidorry   188 #10 Posted March 20, 2019    I was just asking because I took my car in for a monthly health check and they said that one of my tyres was at 4mm and would need changing when it got to about 2mm. So I thought I would get 1 new tyre and have the decent front tyre for the spare and the spare to match the new one but when I looked it was a different size. In the owners manual it states that it should be the same size. I think I will pay them another visit.   Share this post Link to post Share on other sites Share this content via...
Top Cats Hat   10 #11 Posted March 20, 2019 Are you talking about tyre or wheel size? Share this post Link to post Share on other sites Share this content via...
Kidorry   188 #12 Posted March 20, 2019 The tyre size on my car are 215/16 and the spare one is 185/15". Share this post Link to post Share on other sites Share this content via...