35/12.5R20 on stock 20 x 9??

[Rynofire]

Tire shop says 35/12.5r20 will fit on my stock 20 x 9 wheel on my Bighorn, but will that width hit my upper control arm???

 

[DonsRam19]

Tire shop says 35/12.5r20 will fit on my 20 x 9 wheel on my Bighorn, but will that width hit my upper control arm???

I'd get 11.50's then you won't have to even worry about it.

 

[nicodywill]

Tire shop says 35/12.5r20 will fit on my stock 20 x 9 wheel on my Bighorn, but will that width hit my upper control arm???

I have a Lonestar (ie. Bighorn) with a 2.5" level and can tell you now you’ll rub on the UCA’s with stock +19 9” wide and 12.5’s, and super close on an 11.5" wide.
I ran 285/65’s (11.2 wide) on the stock 20x9 +19’s for a bit and there was about 1/2” of clearance between the tire and UCA’s.
You'd have to come out further in order to get 12.5’s under without rubbing anything on the inside and then you start to hit on the edges of the fenders.
I just tried to mount my 285/65's on my leveled truck on a 20x10 -19 and even that was rubbing on the edges of the fenders..

 

[nicodywill]

I am planning this exact setup - 2.5" level, 35x12.5x20, on stock 20" rims (+19 offset). Should I plan on having spacers (1" or bigger?) on hand just in case, or absolutely?

spacers or not it wont fit without modification to the fender wells, you'd have to cut.