What to know about pulling your fender liners

I put 255/80/17 Cooper ST Maxx tires on my truck last fall, after putting on the 2" OME lift with Dakars in the rear and Total Chaos UCAs. I'm running stock 4runner wheels and got minor rubbing, mostly on the inner fenders. So, I pulled them off and now have some experience with mud and dust and wanted to post some information for those considering this.

I put in a K&N air filter and left the air intake stock. I knew this was something that would have to change, but wanted to see what the outcome would be. On an elk scouting trip a few days ago, I drove about 175 miles on forest roads ranging from just-graded to nearly impassable. I've driven the same roads in the spring when they were muddy.

On the most recent trip, I realized I was getting shit fuel economy, even with my mods and being in low gear, +/- 4wd, +/- low range a good bit. I figured I'd better check the air filter. This is after about 5-6k miles. You're supposed to get 50k miles without a cleaning with "normal highway driving" and, I assume, an unmodified air intake apparatus.


The grit to the left came out of the filter. After cleaning, the filter looks like this:


An intake reroute is next. Probably the cowl relocation that has been documented elsewhere on the forum. I would recommend to anyone else to plan to do a snorkel or the reroute at the same time as removing the fender liners.

The K&N did its job. This is the screen on the engine side of the air filter, as it was when I took the K&N off. Clean as a whistle:



This is a shot of the intake assembly right where it attaches to the filter box, and how much debris had collected in it:





Here is a shot of the opening of the intake tube in the fender. The tube is in fixed position, meaning the opening can't be rotated to alter the direction the opening faces:


And, the side of the intake tube closest to the air filter. Cleaner, but obviously fairly large debris gets all the way to the filter assembly.



Aside from air intake concerns, there are some other considerations. You will get mud and dust EVERYWHERE. I've had muddy water leak out from around the headlight assemblies (just from driving on wet dirt roads - I don't take the truck "mudding"), and it collects up in the fenders and in the inside of the rear bumper like crazy. Here are some pics from around the truck after the elk scouting trip.


Full engine bay:


Battery area:


Passenger side headlight/windshield washer reservoir area:


Passenger side near the hood hinge:



This shows how deep the mud had pooled and dried in the passenger hood hinge area (probably 1/8 - 3/16"):


There were rocks and leaves in hood hinge areas. Leaves, twigs, small gravel, etc. Also, mud really gets caked in the upper corner of the inside of the fenders by here.



Pretty poor pic trying to show mud caked inside the rear fender area.


A few other considerations:

1) I get more dust in the cab now that the roads are dry. I think the wheels throw the dust into the far upper rearward corners of the front fenders and it eventually works its way in through the door jamb.

2)My bed seems to get more dusty under the canopy. I think it works its way in through the drain holes in the bed and storage cubbies. This has inspired a separate dust-proofing project I'll do and write up at a later time.

3) I get more dust in my gas cap area. The hinge on it broke last fall and that is certainly some of it, but the missing fender has to be part of it, too. Not a big deal regarding gas, but I know some route doff breathers here and that may be a consideration for that mod. Probably fine, but just throwing it out there.

Now, to give you some reference, my truck is now retired from daily driving and is used for hauling stuff and pursuing outdoor pursuits like fishing, camping, and hunting. I drive it anywhere I want to go where there aren't obvious obstacles that will cause more than cosmetic damage. The following pics are for you to compare how you use your truck and decide if you will have more or less issue than I do. Mudders or people who drive in the desert or dunes will have more issues. I also didn't get to see how much snow packs up in the areas this winter.

I drive this kind of road frequently:


This is about as muddy as my truck gets:


The roads I drive lead to a lot of pinstriping and encounters with brush:




I average about 15mph on the ~50 mile loop I drive for most of my hunting scouting. Some stretches are steep and rough and I use low gear in low range to save my brakes. Other stretches are good roads with gravel where I do 45mph.

My overall recommendations:

1) If you don't HAVE to do it for clearance, don't. Not sure why you would, but just sayin'.

2) If you do it, do something to alter the stock intake at the same time. Check your air filter after every trip off road until you're sure your new location is preventing my issues. Plan on thoroughly spraying out inside the fenders and bumpers after every trip with mud to prevent rust. Crawl under it frequently and make sure mud isn't accumulating somewhere. And expect more dust/mud everywhere, even places you may not expect. However, if you have realistic expectations and have to do it, none of the issues I've encountered have been deal breakers for me.

3) All the above said, I am contemplating a couple of options to reinstall some kind of barrier back in the fenders that will provide more clearance and some level of protection. If I find anything decent, I'll post that info as well.

Hope this helps someone. Let me know if you have questions. And anyone else who has experience without the inner fenders feel free to post your experiences, too.

 

ducting to the cowl works pretty well. had it for a little over a year and my filter was dirty but not bad.

 

OP, Thanks for the detailed write up. I am currently fitting 35s on my Tacoma and am diving into the hole of tearing out all things that rub (more than I expected). I was reading the forum trying to figure out a way to relocate my intake because of the lack of inner fender linners and came across your post. I didn't realize that there would be so much headache with removing them. Just wondering if you have discovered a solution to all the dirt/mud/debris that goes into the engine bay etc without the factory fender linners?

 

I recently installed Fend-X fender liners. They still need some trimming, and I may need to try to mold them with a heat gun. It amazed me how much mud and debris got up in the fenders. I spent close to an hour hosing out all the crevices and ledges and still missed some.

 

Ok yeah I checked those out. They look like decent product. Just curious, but do you have your splash guards removed as well? Wondering if that had something to do with the amount of debris you're getting in your engine bay. I have the splash guards from Geartech customs and they work great.

 

I have the factory splash guards and they have several broken mounting holes. I’ll replace them too, I figure.

 

Old thread, but incase you didn't come up with a solution yet, I made some new fender liners pretty easily. I used cardboard to make a pattern of the rough shapes I was going for. I then found 4x8 sheets of 1/16" abs plastic sheeting. Traced my pattern and used tin snips to cut them out. I still haven't installed them as I'm waiting to trim my fenders by a couple inches and will lose most stock anchor points. I'll be using L brackets to secure the new liners.

Front 90% done. Will do final fitment trimming when i install.


Rears