I know that the cognito leveling kit / uca install has been beaten to death many times and many pictures and reports have been posted...

But I am still not certain whether or not my 18 x 9 wheels with 5.5" BS will fit or not.

According to cognito they will not fit with the their ucas (or leveling kit) installed and looking at all the pictures that might be true. The cognito uca looks wider at the front because of the newly designed ball joint and probably thats the reason for this.

I am running these wheels with zero tb cranking and 285/60/18s without any problem but would like to install 325/60/18s using the leveling kit. Surely I will not use any spacer, I have chosen that 5.5" BS wheel for the reason that the tires are not protruding so far out of the fenders and to minimize stress on the bearings etc.

305/65/18s might be fine as well but I don't like BFGs and they are the only ones coming in that size if I remember correctly.

Any idea is greatly appreciated! Thanks! :rolleyes:

I know that the cognito leveling kit / uca install has been beaten to death many times and many pictures and reports have been posted...

But I am still not certain whether or not my 18 x 9 wheels with 5.5" BS will fit or not.

According to cognito they will not fit with the their ucas (or leveling kit) installed and looking at all the pictures that might be true. The cognito uca looks wider at the front because of the newly designed ball joint and probably thats the reason for this.

I am running these wheels with zero tb cranking and 285/60/18s without any problem but would like to install 325/60/18s using the leveling kit. Surely I will not use any spacer, I have chosen that 5.5" BS wheel for the reason that the tires are not protruding so far out of the fenders and to minimize stress on the bearings etc.

305/65/18s might be fine as well but I don't like BFGs and they are the only ones coming in that size if I remember correctly.

Any idea is greatly appreciated! Thanks! :rolleyes:


I don't know if this will help but I spoke with Chad at Cognito about a tire rubbing issue on the Cognito UCA with the 4"-6" kit and he told me that if you use a rim with 5.5" of BS (like an H2-17x8.5) you cannot use a tire wider than a BFG 315/70/17 on that rim. A BFG 315/70/17 has a section width of just under 12" on an 8.5" width rim. I don't know about an 18" rim but I would guess you still can't use a tire wider than the section width listed above. I plan on putting H2 rims on my rig and I wanted to make sure there was no rubbing issues with the tires on the UCA's.

Rim dia also plays into this.
A larger wheel dia should allow more backspacing.
I remember my neighbor having 6.75 backspacing on a 20" wheel and clearing the UCA.

I have 295/70/17's on h2's (5.5 bs) with 1/4" spacers right now and still rub the UCA's on the tires.

there are a few tires availabe in 285/65/18...I think they measure just under 33 inches.
im think you can get nittos and a few others besides bfg's

325's with 5.5" backspacing is a no-go. I have 315's with 5.25" backspacing and they rub the control arm