I will be installing 1.5" ball joint spacers on my 93 4runner soon and have read the whole IFS lift thread and didn't see much about the need for wheel spacers on factory rims so the tires don't rub the uca. I don't think that will be an issue since my 31" buckshots are only 9.5" wide but I was still going to install 1" spacers on the front only but after reading the front is already wider then the back I was wondering if it would cause any handling issues.

and just to make sure I need 6x5.5 spacers? I was going to go with .25" shims but think 1" adapters will be safer.

 

Don't really need spacers with the stock wheels. If you add spacers you might hit the frame or the fender at full lock/stuff. Definitely pass on the shims tho if you're dead set on widening the front. just go with the adapters.

 

you need to take care when trimming the upper control arm for ball joint spacers..
Insure the spacer is as far outboard as you can make it,
take no more than is needed,
weld a 90° backer after you trim to reestablish the stiffener lip and give the spacer something to rest against.

If you take to much, they will rub, if the bracket shifts they will rub, if you're off level (sideways on a hill) they will rub, if you under inflate they will rub.

​​​​​​​Note tire width is given at the rim, the tread can have a wider contact patch, aswell the side wall will bulge outwards based on design and air pressure.