Bigger Tires + More Aggressive Wheels - To Body Mount Chop or Not?
- on June 27, 2021
- Categories: Lunar Rock TRD Pro - Project 4Runner
Thats the question I had on my mind for weeks! Would I have to have a shop perform the "Body Mount Chop" aka BMC on my 2021 Totoya 4Runner after running a more aggressive wheel and tire setup?
So let's back up a minute. Before I lifted it, I ran installed the Spider Trax 1.25" spacers on the stock wheel and tire setup. It would rub right on the lip of the bumper, right behind the black fender liner. I trimmed that to avoid the rubbing knowing it would be necessary eventually.
On all the forums and Facebook groups the opinions of others always seemed to vary when this question was asked. Being that there are so many different wheel/tire setups, variety in lift kits, and of course the offset of the aftermarket wheels - it made sense. No real concrete answer!
Now the Westcott Designs lift kit is advertised as being able to fit the 285/70 tires (inch wider and almost an inch taller) without any modifications at all on the 2021 Toyota 4Runner. Their lift raised my car 2.5" on the front and 1.5" on the rear. Pretty significant. Now Westcott bases this on stock wheels. Once you get more aggressive offset wheels like I put on this 4Runner, you essentially throw what Westcott said out the window. Doesn't apply any longer!
The Volk Racing TE37xt wheels installed at 17x8.5 -10 offset. This pushes the new wheels out the same amount as I had before WITH the SpiderTrax spacers and stock wheels. So of course with wider tires I would have some concerns.
I took the logical approach. Prior too committing to see IF I needed the BMC, I took off the spacers and installed the new wheel/tire setup. Right off the bat I heard rubbing. Pulled back in the garage and took a look. Rubbing on mud flap and on the back fender liner.
Now with the mud flap you can remove it and see if you rub on the body mount. If you are rubbing not he metal itself, a body mount chop is required. No way around that. If you are rubbing only on the mud flap plastic you can remove the flap or heat it up and push it in. I decided to keep it on for now, push the part that protrudes out inward after heating it with a heat gun. I also drilled a small hole to mount a zip tie through it - this allowed the flap to pull toward the rear of the vehicle giving even better clearance.
The front is just as easy. You unscrew the 10mm screws on the bottom of the bumper on the sides. You will feel the black liner is now loose and it can be pushed forward. Drill a new hole in the black liner and screw it back in position. This gives an extra inch or two of clearance for the wheel. Rubbing only occurred at full lock and you test it by turning the steering wheel. My clearance issue was resolved with plenty of room!
So if you are here still wondering if you will need the BMC on your 4Runner, the answer is still uncertain. There is a good chance you won't assuming you are lifted high enough and you make the proper clearance on the plastic liners, bumper, and flaps. If you want that super poke look with extreme offset wheels, you will no doubt need the BMC done.