RV-DE-FENDER install and info on Fuzion 420 ... I have real metal fenders now!

twvette

Senior Member
Joined
Dec 4, 2016
Posts
205
Hoping to never have to see this damage as well as all the hidden damage including floor again!
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So now have these ...
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Not sure too many people are aware “real fenders” are now available for your trailer, so figured would do a detailed post on this and my experiences/tips. They are called RV-DE-FENDER by a small business out of Utah RV-DE-FENDER® Tire Blowout Protection System and just great people to work with in general. If the price is shocking, I can tell you it came out to MUCH less than the damage caused by a blow out and I even got lucky.

I purchased them after having my first blow out on G-rated 110 PSI tires. Always feared this day as my occupation is in the pressure world and I knew would likely cause a lot of damage if ever do blow with no real protection above the wheels. Thread related to repairing the damage myself will be posted soon and will add link here when does **********************************************

I was further convinced these were a good solution after talking to the vendor. I have had a thought for a long time that needed something around the tires to “chop up” the delaminated tire tread rather than just letting it be a destruction whip so was curious about their design. They explained that the fender sits close to the tire so that the delaminated tread does not gain much momentum and will have no place to go except to rotate back to the front side and into the ground where it will eat it up instead of the trailer body trying to do this. They are also clocked rearwards so thus the tire in front of it has protection as the blown tire tread comes around to help protect it instead of take out that tire too. They also sit a little more towards the inner side of the tires as when one blows out and the axle drops it will pull the delaminated tread towards the inside and helps with clearance issues to not cover more of the outer tire tire. All made perfect sense to me. A side benefit is they also block almost all brake wiring on the inside from the tire taking them out too (one of my brake wires was taken out).

Purchase was easy and received quickly. It’s a lot of stuff for my triple axle. The inner support system of multiple pieces attached together is crazy beefy. The outer fender supports are also beefy. The fender itself seems to be adequate and not sure you really want much thicker here.

The install is not hard but is very involved with a lot of pieces. This makes sense to be able to ship what otherwise would be too big of pieces. They have a couple good videos for this and will support you with any questions. Unreal customer support actually for me as my install was more involved than most and got immediate responses!

They basically install onto special studs that replace the studs attaching the entire wheel/brake/hub assembly to the axle.

Good chance need new tires if have a blow out. The DE-FENDERS are designed for 235/80-16. This is a slightly smaller tire than the 235/85-16 mine came with and they very liekly would have rubbed a little. Glad spoke with them first so could check everything for fitment so went with the new tire size.


Install:
Highly recommend having someone help. Even a kid of spouse will help a lot as just lots of pieces need to be handed to you while roll around on ground installing them and a lot of nuts/bolts.

Their videos cover most of this so follow them. Here are some added tips, etc ...

Consider installing new brake assemblies and hubs while doing this. Its not much more work to do these (.vs. doing it later) and most overlook servicing/replacing these in general. I have Dexter 7k axles and found places like Southwest Wheel has full kits for this with everything in one part number/kit. Few know this either and many big retailers do not offer these. They were Dexter direct part numbers I ordered but also 3rd party brands a bit cheaper. Much cheaper than doing individual components too. The hubs come with pre-greased bearings and seal already installed which is a big advantage! I will warn they don’t come packed well so the bearing caps will likely be damaged when received so might have spares of those available/re-use old ones. Painters Multi-Tool (i.e fancy durable putty knife) is the best tool for getting bearing covers off as thin edge to get under cap edge and strong enough to use hammer to get under cap edge and ten pry with. Using proper bearing dust cover install tool works much better than wood block or similar also.
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It’s a messy job anytime with brake dust and grease … be prepared

Laying out all pieces like shown in video really does help. It is a bit of a “puzzle” to get the backing plates installed but gets easier with each one completed.

The special studs were a little confusing to me. There have been some changes to them also. The key thing to know with them is one spacer goes behind the brake assembly, then will have the flat edge part of the stud shaft, and then the other spacer gots on the other side of this.
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The backing pieces are machined for a very precise fiton the axle studs and thus can be a challenge to get them sitting properly and aligned so no gaps between the multiple plates that form the single backing layer. Would leave loose each of the stud bolts that holds the brake assembly on. Initially tighten them and then just break each loose as don’t need or want much play in them. This allows the studs to pivot a lot more than you might think (too much sometimes). Can use a screwdriver to pry on them a little to get the studs to move a little to get each backing plate to slip into the multiple stud holes fairly easily when they are loosened. It was a real struggle when they were tight for me.

Installing the actual fenders can be challenging. Since it is rolled metal they just wont sit perfectly when first put them on and bolts are intentionally short length. The key for me was to do all the bolts at the top first. Can pick up on the bottom of the fender to get the bolts in easily. Also, don’t worry about the other half of the fender sitting what seems slightly on top of the other half. If you try to get them with no overlap it just makes it a real struggle to do all the bolts and no benefit in end. Just let them sit where they want at the top as long as all bolts go through. When you then let the fenders sit the weight will help a little get the bottom side bolts in. Still need to do a little aligning and might need to use a Phillips screwdriver or similar to go through the mounting plate and fender hole to pry on it a little to help get all the bolts in. Obviously don’t tighten any bolts like the instructions say until all bolts are started. Don’t use 12 pint sockets to tighten the slim nuts as they don’t get much grab with the angles at play. Use a 5 point socket and need good angles, especially if carefully using a low power electric drill to make this easier. High power impact not good for this.

Having a combination of sockets, ratcheting end wrenches, and standard/open ended wrenches helps in general as A LOT of nuts and bolts and some are tough to get too.

I have used the special Nordlock washers for years now tha this kit also uses and I can also say they are just much better (great for CV bolts that come loose on off road toys). Note they can come separated and there is two different side that go together so be aware of this.

My axles had the brake line holes drilled in them right where the back plates sit in the axle so this struggle made the install a bit more involved for me. They don’t build any trailers exactly the same so be prepared for a challenge or two haha. You might check these to be prepared as slowed me down. You can just run the wires over the top of the axle to the other side but my OCD would not allow this. Over the axle and properly secured on top is a Dexter approved fix actually and some do this regardless because if the wires going through axle lose their insulation and start randomly shorting it is very hard to diagnose. I just bought 50ft roll of good two wire 14g (overkill … seemed like they use 18g) and re-ran the wires through my four season/under belly corrugated plastic sheets to for the other side. Just fished it through with steel wire puller tool after removing some of the bolts that holds the material to give some better visibility but was a little tricky. Will want some closed end crimp terminals etc. to properly re-connect the wiring. Will also need to secure the wiring next to the axles with axles all the way extended down so have enough length and that does not get caught up in leaf springs.
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Just my luck I had a third struggle most wont have. My Fuzion 420 has a side patio and the subframe for it significantly limits the travel of my front axle before hits it. It actually rubbed on a frame support piece when purchased new as well as would kiss the patio subframe every now and then. With these fenders added on top I have about 1in less clearance than before so knew something would need to be done. Went with Sumo Springs. Added an extra 1/2in washer on top of the two already supplied and a longer bolt, so I have a total of three on each side of that axle so they act a bit more like a bump stop. These squish a lot more than you might think (or compared to Timbren springs I have used in past). Very easy to install these as they essentially just clamp over the existing leaf spring u-bolt plate. It comes with a fuel line relocation kit which was a nice piece of the Sumo kit that I did need to use so be prepared for that also but was easy.
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I honestly thought the looks of these would really bother me, but in the end I don’t see it that way. They blend in fairly well since sit’s so close to tires and they are black so just don’t stand out too much. If nothing else it kind of reminds me of a large boat trailer where fenders are tucked up with large hull sitting above … or maybe this is just what am telling myself to feel good haha.
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Why trailers like these have no protection above wheels is rediculous. All should come with something like this or similar IMHO!
 
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There were a couple of threads about this product several years ago. They were new and unproven at the time (by the general public). Have you had any experience with how well these protect the trailer during an actual blowout? Or are you hoping that what you installed helps in a future blowout???

The reason I ask the questions "that way" is because I've seen a tire tread separate from the carcass and completely slice through a 1/2" black iron pipe. The walls on a black iron pipe are substantially thicker than the sheet metal on these devices... I've never been able to talk to a "blowout survivor" who had these installed, so no personal experience either first hand or from people who have prevented damage by using them. If they work, great, but on the other hand, not knowing anyone who has experienced a blowout with them installed, the "jury is still out" so to speak...
 
.... I've never been able to talk to a "blowout survivor" who had these installed, so no personal experience either first hand or from people who have prevented damage by using them. If they work, great, but on the other hand, not knowing anyone who has experienced a blowout with them installed, the "jury is still out" so to speak...
I am always of the mindset jury is still out on "upgrades" I do. I was not able to find anyone who said they do not work and seems there have been hundreds of sets sold. I went 9 years with no blow out and came out one short trip with current set of tires as went out only 50 miles from home on last trip of dune season and was going to replace just my luck as this set is a little over 4 years old now.

Its an interesting mindset change too. I dreaded a blowout before and lots of OCD to keep proper pressures, etc. Will do the same as still don't really want one, but now it is more of a curiosity of what actually happens and feeling like I will very likely survive it and not take out another tire too as only have one spare as most do. My other side is the a full room slide out with less above it for protection than this side that went and would be a much bigger disaster if went on that side, so I still got lucky. Now I am not really worried much at all. I have had friends with their rig at the dealership for repairs when takes out the floor for 6 month while they make payments and cant use. I suspect will just dent up the DE-FENDER a bit and take off a lot of powder coat from he fender but that is an easy fix. They have videos driving around with a blown tire which also gives me some further confidence, but the theory makes sense too.

I still think its key to realize the fender close to the tire wont allow the tread to become a whip. No surprise it went through a thick piece of metal as once it gets some room to whip that is exponential more leverage/force of a lot of steel itself. Most will think just a metal plate a foot above on the frame will help (and it should a bit if really thick), but by then the whip of tire tread is already destroying a lot of the skirt, plastic fender, etc.

I did the repairs myself as dealerships were way backlogged and figured might as well try and never go through this experience again and take the insurance check and do something preventative with it rather than just put back to same state as prior.
 
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I like the fenders but I'm just as interested in those Sumo springs. I thought they were bags at first.
Yeah, I am digin' them too. I think they would be good to install when new to help support the leaf springs over time as I know a lot of people have to replace their leafs fairly early. They are soft enough that should not make ride much harsher yet provide better stability (but not an issue for me). I just have them on my front axle for the bump stop purpose currently, but might order for all when do the leaf's as mine are getting to that point of needing replaced but I got good life out of them. Here is a pic that shows how much they compressed under full static load in my testing and why I am adding one more 1/2 spacer to get them for more bump stop purpose, wowza:
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I installed RV Defenders on my 23MLE last fall. This is my first camper. I have seen pictures of damage from blowouts and decided to be proactive. Hopefully, I will never find out how effective they are.
 
Won't let me edit any more so here is some further info ...

Here is the post for the repairs:
Repaired the damage after a tire blow out ... Fuzion 420 and general info

I did need to trim the side skirts a bit to get the RV-DE-FENDERS to clear my skirting along with pushing out the skirting a bit on the patio side. Just expect some potential challenges but this was fairly easy to make happen.

The close fenders might also serve as a point of reference for when a tire might be about to blow. There is info out there that they start to swell before delaminating so might be able to catch this if pay close attention.

The fenders might come in contact at some point depending upon the spacing of your axles, tire sizes, etc. I found my front and middle axle will cause my tire to very slightly kiss the fender after bench jacked up off ground or when going through something that causes middle wheel to drop down a lot. The axles move around a bit so this can happen. They pointed me to Herculiner Bed Spray as a perfect touch up and I can verify this indeed works. I had some minor shipping marks initially on a couple and just touched them up with this and perfect match when dry.

I put the finishing touches on the project this weekend by adding in the 3rd 1/2in spacer with longer bolt (M8x60mm) on the Sumo Springs and securing/protecting the brake wires a bit. The factory wiring just has them hanging and secured on the back side of the brake assembly. The factory wires were a little beat up from 9 year of use so bought some 1/4in high temperature/automotive grade braided wire sleeves to wrap them in and the other new wire is already sleeved. My brake wiring was a little different as mentioned above not being able to use the holes going through the axles for the brake wires to go to the other side, but would still have a wire hanging down behind the RV-DE-FENDERS. I ended up drilling a 1/4in hole in area where only go through one or two of the backing plates for them and using a tree style push in zip tie. I forgot to just remove the clips Dexter provides on the new brake assemblies as could have made them work also in a small hole.
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Couple more random pics just showing the RV-DE-FENDER's are beefy where they seem to need to be:
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There were a couple of threads about this product several years ago. They were new and unproven at the time (by the general public). Have you had any experience with how well these protect the trailer during an actual blowout? Or are you hoping that what you installed helps in a future blowout???

The reason I ask the questions "that way" is because I've seen a tire tread separate from the carcass and completely slice through a 1/2" black iron pipe. The walls on a black iron pipe are substantially thicker than the sheet metal on these devices... I've never been able to talk to a "blowout survivor" who had these installed, so no personal experience either first hand or from people who have prevented damage by using them. If they work, great, but on the other hand, not knowing anyone who has experienced a blowout with them installed, the "jury is still out" so to speak...
I'm not sure that is a fair comparison. Black iron pipe is actually very brittle when subjected to a large shock load.
 

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