There are probably dozens of wheel openings that can be used to fill the gap on the big truck fenders that would work out great. If there is a local source where a guy can hold in his hand a wheel arch patch piece from a few different vehicles, he could probably choose one that matches up with the fender curves pretty well. I've done this in the past, and it works out pretty well. The problem with that concept is until you can put the new piece against the fender, you really can't tell how close its going to be. if you have to order a patch panel from someplace and then find out it just won't work, what can you do then? Will they accept the return, is there a restocking fee, and how much is the shipping cost both ways? A guy may soon have a collection of wheel openings because it cost more to send it back then it was worth. The fenders on these trucks have a pretty dramatic compound curve just past the wheel opening, especially on the big truck fenders. A nearly flat panel with a reinforced opening lip may not conform to that compound curve very well, or it might work out good. Then the patch panel needs to be long enough to reach both sides of the Dodge fender wheel openings.

Before you get too involved with any of this, you really need to have the fender bolted in place. To bolt the fender in place, you probably will have to trim the lower part of the fender (the heal of the fender) near the cab. Do that 1st, before you deal with the wheel opening. I say this because often times, when the fender is bolted in place, it is at a different angle (and location) then you thought it would be in.

Most of the time, a guy can buy a pretty large piece of 18 or 20 gauge flat sheet metal for less money then one wheel arch parch panel. Then he can use the excess metal for other patches he may need. The top of the wheel opening on these Dodge fenders has a pretty flat arch to them because Dodge basically opened them up for the front and rear tire clearance when the wheels were turned. Basically, all that needs to be done is to put back the part Dodge removed from the front of the wheel opening, and put back the part Dodge removed from the rear of the wheel opening. Those pieces are a basic triangle shape, one point is towards the center of the wheel opening, the bottom point is the bottom corner closest to the tire, and the 3rd corner is where the patch piece meats at the end of the original wheel opening front or rear edge. Use the cardboard material that holds your favorite beverage to make a cardboard pattern for the front of the wheel opening, and another cardboard pattern for the rear of the wheel opening. Cut and trim the edges so you have enough cardboard material to cover the areas you will need to weld, Tape the cardboard in place, then make the curve you need so it looks right to you. The nice thing about using cardboard is if you screw it up, you may be able to tape it back together, or you may have to drink more beverage to get another piece of cardboard. That cardboard pattern can be used for both front patch panels, or for both rear patch panels. You will probably want to round off the corner closest to the tire, and the side near the tire, and the side at the bottom that covers the gap between the original fender and the tire will need to be reinforced a bit.

Once you have your pattern the way you want it, add 3/4" to the full length of tire edge. This extra material will be bent back against itself. You will also be adding an extra 1/2" of material to the bottom edge of the patch, This extra material will be bend at about 90 degrees in (if you rounder the tire corner, add an extra 1/2" to that edge as well). When the pattern is done, transfer it to the metal (including the extra material). Mark your edges and cut the metal to match the pattern. Keep the pattern for the other side.

The curve on the tire side is the first part to form. Make sure you have a good visible line for your curve. Using a fairly narrow plyers (about a 1/2" jaw width), slowly begin bending that extra material towards the inside of the wheel opening making sure the end of the plyer jaw is at the line. You want to bend a few degrees at a time, all the way around the curve, then start another round of a few more degrees of bend all the way around the curve. Repeat the process until you have about a 90 degree bent lip At that point, a light hammer tap along the bend should smooth out any kinks in the bend line. Then continue with the few degrees of bend all along the again and repeat until the bent edge is nearly as flat as the plyers will allow. At that point, the remaining bend is done lightly, and slowly with light hammer tapping. Use the flat head part of the hammer, very carefully, being sure the hammer contact with the metal is light and square with the surface. Place a very smooth piece of thicker steel on the outside of the patch piece and from inside of the patch piece, lightly tap the bent edge together, all along the curve a few degrees at a time, and repeat until the surfaces are tight against each other. Any flaws in the smooth piece on the outside of patch will show up on that surface, and if you hit it too hard, that will also deform the outer surface. Once the gap is pinched closed, you can form any curve you need to match the fender curve.

You also need to add a reinforcing lip on the bottom edge of the patch piece. On this one, add a 1/2" of extra material (if you have rounded the tire corner, add the extra 1/2 inch to that area as well). The same process is used on the bottom edge as was used on the curved edge, except you can stop forming the edge when you get about a 90 degree bend towards the inside. I suggest you make one front patch and one rear patch for one fender using the same process and tack everything in place, then do the other fender.

The patch piece should be clamped to the fender and positioned as desired. Once happy, you need to mark where you will be welding the patch onto the fender. That area that will be welded needs to be shiny clean on both sides o\f the fender. Once cleaned up, clamp the patch to the fender and tack it into position. Be sure its properly located before you fully weld it. its much easier to cut a few tacks and reposition then it is to cut a fully welded line to reposition. I would recommend that you make and tack both the front and the rear patches on a fender before you fully weld it. Gene