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2064 Views 8 Replies 5 Participants Last post by  Katshot
Our 76 Calais calls for 235-75 R15 tires. We have a chance to pick a bargain pair of 225-70 R15. Does anyone know if there is any problem putting these on the car?

Thanks in advance,
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Anytime you want to change tire size, I would suggest going to
and checking the tire dimensions first. Off the top of my mind, I would say that your tire choice should be fine but remember that the 70's will be a little lower (smaller diameter) , but wider, so the wheel wells will seem even LESS filled-up with the 70's.
I used to do the "75-series" to "70-series" swap on ALL my cars but I also made sure to "fill them wheel wells" by staying with the same (or larger) first number. (example: stay with the 235's and don't drop to a 225)
Mackenzie said:
Thanks guys. Just so I am clear...if we drop from 235/75/15 to 235/70/15 this will work otherwords, will it effect the ride, safety or tread life.

That depends more on the tire type, and manufacturer than the size (especially only changing just one size).
The size change will provide you with a slightly lower profile, but slightly wider tire. Generally this slight size change will not give you a problem. All things being equal, the ride MAY end up being slightly firmer with the added benefit of better handling.
HotRodSaint said:
If it's a deal, go ahead and do it.

And here's two great tire sizing sites to help with these questions.

Nice sites :thumbsup:
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