I have been looking at getting some 20x9 wheels.
I am debating between 18mm and 0mm offsets.
I do plan on using my stock hankook 275/55/20 ATM's.
I do NOT plan on leveling or lifting my truck.

I do have weathertech front no-drill mudflaps, and really prefer to keep them on.
If I get 0mm offset, with the stock tire size rub on the mudflaps? I am 99% sure the 18mm wheels wouldn't

 

I have 20x10 with 0 offset on mine. Leveled, with 305/55-20 with a riveted on Ford flat mudflap. At full lock the tire just touches the mudflap enough to rub a spot clean.
Your tires are half inch narrower and about an inch shorter than mine. I would think you would be ok but yours not being leveled and mine is I guess it is not a direct comparison.

 

I run 285/70/18 ridge grapplers with a 18 offset on my truck with a 2.25 level and I ended up cutting off 3.5'' from the inside of my weathertech's to make it work.

 

Blah, that's not what I wanted to hear.... Any pics of how you cut the fenders?

I may look for wheels with 18mm offset instead of 0mm... too bad the moto metal 962 dont come in 18mm!!!!

 

I think he meant that he cut the weathertec mudflaps

 

Thanks,^ all I did was turn the tire until it made contact with the mudflap, marked it then cut it...done. No problems. I have the moto metal 970's 18x9.

 

oops, sorry, mine are 305/50-20 not 55s

 

I have -18 off set with 35/12.5/20 with a 4” lift and mine rubbed half way thru the mid point of the flaps, they had to go!

 

Thanks for the replies...
I do not plan on a leveling kit so would love someone to reply that also doesn't have a level.

Right now I prefer the moto metal 962 in 20x9 0mm (wish they came in 18mm)
But I guess I could also settle for the gear big blocks as they do come in 18mm