Will I notice or see that big of a difference if I currently have backspacing of 5.00" and an offset of -15 and I will be going to backspaing of 4.75" and an offset of -19? I am not sure what the offset does as far as how far the tires stick out. Thanks.

 

The wheels would be pushed out .25", assuming the wheel width stayed the same.

 

RIght. Backspacing and offset are just two different ways of measuring the same thing. But knowing the BS and offset are basically useless without knowing the wheel width.

 

Sorry both set old and new wheels are/will be 20x10