Front bumper trimming, by Kevin Fell
Ok, here’s the deal with trimming your bumpers: It’s easy…really easy…you just have to have a little bit of confidence when you cut into your fresh bumper fascia. Here’s some things to help your self-confidence level before you start. Also, if you start trimming VERY small amounts at a time, you’ll get a feel for how the process works, and then you can stop when you think you have a good amount of clearance and a good straight line. Here are some tips that I can offer you:
I like to use a pair of sheet metal shears. They leave a nice, clean line and are easy to operate. In the past I have also used a saws-all (too fast, blade melts the rubber/plastic bumper), a coping saw (on it’s lowest setting with a plastic cutting blade, it works, but again, it’s fast, so you have to be very steady) a razor knife (a lot of work, but straight cuts if you use a steel straight-edge) and a Dremel (again, melts the plastic, makes a mess). Ideally, you’d keep your stock backspacing, as you’re going to have more bumper clearance around your larger tires with more backspacing than with less backspacing. With a tire slightly too large for your wheel well, typically you’re going to rub under the front bumper, when the tires are turned about 1/2 the way left or 1/2 the way right. It will be on the outer lower edge of the bumper…the place that is the closest to the tire. If you take your bumper fascia and measure forward say 1.5″ at the lower lip, mark it with a pencil, then make a diagonal line with a straight-edge upward to meet the point where the trim line (the recessed bump) ends at the wheel well, what you’re left with is a long, triangular section of bumper that you can trim. You can use a piece of masking tape (the blue stuff works best) to mark a nice, straight line, and then cut at it’s edge. You can also visualize how it’s going to look BEFORE you start cutting. Once you complete the trimming, take a flat metal file (not a course wood file) and chamfer the edges and it’ll look like new…or at least never noticeable to a non-Jeep fanatic. A lot of people are weary about this minor project…it’s really not a big deal…just jump into it and you’ll do a very nice job. You can always trim another 1/4″ further forward if you had an ugly line or a ragged edge.
If your tire is a fairly large one and you are running factory backspacing, then you might find that you also may rub the inside of the tire’s tread on the outside of the lower control arm when turning sharp. On the XJ/TJ/ZJ, all you have to do is add a washer to your steering stop, which is located on the front side of the axle, near where the knuckle turns inboard. Look for a rusty bolt sticking out where the head contacts the knuckle. Just add a flat washer or two, and that will eliminate that rubbing. If you own a WJ, then you’re just plain screwed. Jeep (or maybe Dana) decided to stop using steering stops in 1999 on the Grands…so just turn your steering wheel less to eliminate rubbing.