Need help!! with installing 20 inch rims on 06 maxima,not sure
what issues i will incounter??

 

none with the right specs

 

what are they talking about when they reference gaps and spacers

 

 

Who are "they"? They talk a lot don't they?

 

I have 20" rims on my '04 but had to make sure I had the right size tires and offset for the rims to make sure there was no rubbing. I have 20x9 in the rear with a +35 mm offset running 255/35/20 tires and I had to slightly trim the inner plastic edge where the bumper meets the fender. I don't recommend rolling the fenders unless your getting it done properly because they will eventually start rusting if you don't.
You can save yourself the headache and get rims with an offset around +45mm and you should have no problems even if you decide to go 275/30/20.

Just pay attention to the offsets, do a little research online and you will see the higher the offset the closer the wheel is to the hub.

Goodluck