Sprinter 4wd Fender Modification
Tire Selection
After a summer of spinning my stock Sprinter tires in the mud and getting stuck more than a few times, it was more than apparent that I needed to get some better “shoes” for my van. Since I was going to get new tires, I thought it also appropriate to check out the options for tires and maybe even new rims. After reading an inordinate number of forum and blog posts on tire sizes and rim choices, I did some shopping. I quickly decided this was not the time to spend $2k to $3k on a full tire/rim upgrade. I settled on a size upgrade to 265/75R 16 which would give me a 31.6 diameter tire with wider tread on the stock wheels. The catch: this tire does not fit in the front wheel well!
Fender Modification Options
Once again, I poured over the online forums and vendors to check out my options for creating a roomier environment. Apparently, the lack of space in the 2019+ front wheel wells is a well-know thing. There are a few vendors that offer conversion kits and some ideas online for increasing space by simply cutting the rubber mudflaps. I noticed that the kits involved a great deal more work than it seemed necessary to effect this modification. A couple of forum posts and my friendly local conversion shop suggested it was just a matter of a bit of cutting to move the mudflap rearward and open up the space.
Marking & Cutting
I began by removing the front mudflaps from both sides. It’s pretty easy process and hopefully obvious where the things are attached, so no photos of this. I also removed the fender liners to give me more space to work. They are held in place by just a few bolts and clips.
I then traced out the portion of the fender for what I needed to remove to gain the 1 1/4″ of extra space I needed. Shown here is the piece already cut out to show the general curve. In my case it actually closely matches where the rear edge of the mudflap overlaps before modification. I started the top of the cut just below the second mudflap mount point (see photos below).
I cut the sheet metal with my angle grinder which was pretty straightforward. (With exception of being nervous about cutting up a new van.) I was careful to not get too sloppy with the cut as this piece is re-used.
After cutting out the wedge-section, I cleaned up the area a bit with the angle grinder and file. Here you can see the upper limit of the cut just below a mudflap mounting tab. There were also some bits on the inside of the fender that needed to be trimmed.
Rust Prevention
I cleaned up the burs and any stray undercoating rubber bits and treated all cut surfaces with POR 15. (This is awesome stuff that I began using when restoring a very rusty 1985 Vanagon.)
Here you can see a mudflap mounting tab still attached to the cutout wedge. This will be used in the remounting of the mudflap.
Assembly
Now THIS is the cool part: The cutout wedge can be fitted internally to the fender so that it forms a new backstop for the mudflap mount. I secured this in place with stainless steel self-tapping screws. This doesn’t have to be pretty since the overlap of the stock mudflap covers these screws.
Notice here that the holes for the wheel-well cowling will match the mounting tabs, so no major mods need to anything else.
Finished
The mudflap may require a tiny bit of trimming to get it to fit snug, but nothing major.
Here’s the mudflap mod with my winter studded tires (sorry about the dirt – it’s winter here). There’s plenty of room lock-to-lock for this 265/75R 16 studded tire.
I think you may be able to trim off even more if you want more space for a larger tire, but this is what I had read would work for the 265’s. Given the mounting angle and radius of the resulting wheel well, you would likely have to do a bit more trimming of the mudflap if you made this any bigger.
