Oh wait, we did do just that...

 

They clearly didn't even try. I run 35x12.5r20's with a 1/4" spacer, they are close to the knuckle but they do not rub. Stock wheels are 5.75" backspacing, using a 1/4" spacer drops that to the 5.5" required.

And the reason a larger tire fits with no lift is because the knuckle isn't nearly as tall as the replacement. With the lift there are no upper A-arm issues as it sits higher than a 35" tire.

 

No, they didn't. That's why this whole thing is confusing... aside from the guys here who say they've done it (and I believe them) the RC kit says all I need is the 1/4" spacers - then when we called them they claim we'd need at least a 1" spacer to run the stock rims with the lift or the tire will rub the upper A-arm.

It's a moot point now I guess, the rims are on the way with (more?) backspacing than stock and they should look pretty sick when it's all done. I'll post pics as soon as I can.

Thanks for the input everybody!

 

Ok so here's a related question. If I get the RC lift (4" or 6", I haven't decided), is there any way to run the stock 17" rims? If there seems to be issues or concerns with the 20" wheels, I'm guessing the 17's are a no go. I thought I'd ask anyway to see. I'd rather wait to buy the bigger wheels if I can help it. I'm either going to buy the 4" with 35's or 6" with 37's. I was looking on the RC website and they're both about the same price. If I can get the 6" for just a little more than the 4" and use my stock 17" wheels, that's what I'll do. Any ideas??

 

I believe most lifts require 18" rims min. to clear the knuckle. Although I do remember someone either here or on another forum running 17's with a 4" or 6" lift. Sorry this is clear as mud but that's what I can remember seeing.

 

Yeah I knew there woud be an issue clearing the knuckles, but I wasn't sure if I could run a bigger spacer or if there was something else I could do to make it work. I do remember seeing someone else running 17's on a lift, but they were aftermarket. So the backspacing might have something to do with it. Just curious if anyone knew if it was possible to do. I'm sure I'll just end up buying new wheels. Go big or go home I guess...haha

 

i have the RC 6 inch lift with 35x12.5 17 on 17x9 KMC XD SPY with 4.53 BS and -12 offset. no rubbing at all.

 

Yeah, but you have aftermarket rims. That's what I was trying to avoid. I don't think I'm going to be able to use the stock 17's. No biggie. It'll look better with the new wheels anyway. At least that's what I'll be telling myself after I dish out close to a G for the new ones...haha

 

The diameter of the wheel has nothing to do with clearing the knuckle. The problem with wheels less than 17" in diameter is they will not clear the CALIPER.
It's the offset and backspacing of the wheel that determines how wide a tire you can run without hitting the knuckle. As long as you have a wheel with around a 4.25-4.5" backspace and a negative offset you'll clear a 12.5" tire.

Don't get crazy on lift and tire height. IFS trucks hate high CV angles. I personally know more than one guy snapped his CV axle running 37" tires on an IFS Ram 1500...

 

[quoteDon't get crazy on lift and tire height. IFS trucks hate high CV angles. I personally know more than one guy snapped his CV axle running 37" tires on an IFS Ram 1500...[/quote]


I'm not sure what IFS means, but thanks for the heads up. Maybe I should stick to the 4" and the 35's.