different wheel size front to back
did any 1978 f100 xlt long wheel base, come with different wheel sizes. i have just purchased one and rear are smaller than front. previous owner did not know why
Someone got cheap and just slapped some tires they had lying around on it. As long as the rear are the same and the front are the same there wont be any issues.
I hope it's not a 4X4. The correct tire size should be p235-75/ R15. And that size should be on all 4 corners. If it is a 4X4, DON'T drive it in 4x4 with miss matched tires.
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