, , , , , ,

Exterior Care & Maintenance Part 2 : Fiberglass Sidewalls, Decals, & Tires

The sidewall of your RV can take a beating from the weather elements such as wind, rain, hail, and especially the sun beating down on it.  This affects the outer skin which is typically a fiberglass panel, decals, sealants, and your tires.


Let’s start with the sidewall’s outer skin.  There have been several materials used over the years including aluminum, steel, and the most popular being fiberglass.  Crane Composites is the leader in fiberglass reinforced plastic (FRP) and introduced the product to the RV industry over 30 years ago.  Most RVers have heard of their signature product, Filon but they also have several other products used in the RV industry.

These products range from the entry-level “ribbed” fiberglass commonly known as “mesa” sidewall to the high gloss material used on luxury RVs.  The basic composition of an FRP sidewall is the base material consisting of liquid plastic and mixed with strands of fiberglass to form a sheet or coil.  These can be colored and are typically available in white and various degrees of beige.  The outer layer gets a gel coat or clear finish which creates a shine.  Economy units have a very thin layer while more expensive units have thicker layers creating more of a shine or automotive finish.

The challenge is keeping the color from fading which has been a huge issue due to UV degradation.  Here is an example of a unit that sat in the California sun unprotected and not maintained.

Sidewall Discoloration

It’s hard to see the discoloration of the sidewall but it has turned to an almost pink hue and the decals show the effects of the exposure.  To minimize this, it’s important to clean the sidewall with a mild detergent such as Dawn dish soap and cover the unit whenever it is not in use.

According to Crane Composites the company that makes Filon, they recommend washing the material monthly with a mild detergent and microfiber rag and doing additional maintenance every 6 months which includes waxing the material.  The gel coat material will change color when exposed to sunlight, heat, and moist air therefore it is important to do the maintenance and reposition the rig frequently to limit full-time exposure to one side.  Crane suggests using Meguiar’s #56 boat and RV Pure Wax which has UV protection built-in.  More information on this procedure can be found on their website here:

If your sidewall already has some discoloration, they suggest Meguiar’s #49 Heavy-Duty Oxidation Remover and a mechanical buffer, then a coat of wax or Mirka Polar Shine 35.  I have also found that Bar Keepers Friend can be used to buff out the discoloration as well.


Vinyl graphics and decals come in an economical “Calendar” style or more premium Cast type.  The Calendar version has a 2-3 year life cycle while the Cast is 5-7 but both can be extended with periodic care and maintenance.  Most of the vinyl graphics I have researched were produced by Sharpline and Valley Screen and they both recommend washing with a mild detergent that has a PH between 3-11 and has no strong solvents.  Use a microfiber cloth and do not wash cold material with cold water.  Water should be over 70 degrees as cold water can shock the material and the adhesive will delaminate from the vinyl.  If using a pressure washer, keep the tip at least 12 inches from the material and the pressure at or below 1200 psi.  They do not recommend any type of wax as it can keep the vinyl from “breathing” and cause premature fading and cracking.


It has been said many times that tires are the most valuable component of an RV but also the most neglected.  There are far too many campground stories about tire failure on the road and many have suggested it’s not if…but when a tire will fail.  However, proper maintenance and education of weight and tire pressure will greatly reduce this.

Weighing Your RV

It is important to weigh your rig to determine the total weight does not exceed the GVWR Gross Vehicle Weight Rating of your rig, the axle weight does not exceed the GAWR Gross Axle Weight Rating, and find individual wheel position weights as well.  This can only be done with portable scales and you can find weighing teams through the RV Safety and Education Foundation here: www.rvsafety.com

Tire pressure should be checked every time you hit the road with a certified tire pressure gauge and not simply a glance.  You cannot tell the difference between a properly inflated tire and one that has 10 psi less.  AND…10 psi less than recommended pressure reduces weight carrying capacity by 25%!

Cover your tires when not in use.  Sun and heat can deteriorate the sidewalls and create weather checking which can also lead to tire failure.  Clean the tire with a mild detergent and do not use tire shine!  Check your sidewall often for signs of weather checking.

About the author: Dave Solberg: Managing Editor, RV Repair Club

For the last 25 years, Dave has conducted RV maintenance and safety seminars, developed dealer and owner training programs, written RV safety and handyman articles, authored an RV handbook reference guide and logged over 100,000 miles on the road in an RV.

RV Repair ClubRV Repair Club is your go-to online resource for enthusiasts who want quality RV maintenance, repair and upgrade information – a community where passionate RVers can come together to gather knowledge and share their experiences.

Learn more about RV Repair Club.

RV Protect

Micheal S. ~ “Leonard was understanding, thorough, and helped us troubleshoot during the Texas ice storm. We were up and running in less than 15 minutes!”