Here, we define what rocker panels are, exactly how they administer key structural support for your auto, why corrosion frequently occurs, and also once these panels need replacement.

Here, a BMW executive discusses the rocker panel building and construction of the company"s brand-new i3 design.

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For a number of safety factors, a rotted and compromised rocker panel need to be cut out in addition to other rust before a brand-new one is professionally welded in.

On unibody automobiles wright here the body and also structure of the automobile are one, rocker panels provide the structural reinforcement that keeps the bottom of the automobile from sagging in the middle. On more modern-day cars and trucks designed via front and rear crumple zones, the high strength of rocker panels is necessary in developing a passenger cabin area that does not decreate in an accident the means hood and also trunk sections are designed to. We can therefore conclude that rocker panels play an important part as soon as it pertains to safety.

Older body-on-framework vehicles via a sepaprice frame offering assistance are not influenced the very same way by rocker panel rot. However, more recent trucks built via separate frames have begun making use of rocker panels and also various other body components to increase structural rigidity and also produce torsional stiffness - so they play a vital structural role tbelow too.

Visible on this 1971 Cadillac Eldorado are chromed trim pieces comparable to ones that adorned rocker panels and also reduced door sections of most Amerideserve to cars through the 1990s. These were an excellent source of rust formation.
Here is a photo of typical off-road damages. Notably endangered rocker panels such as this one market less structural assistance on rough terrain, are a lot more vulnerable to rust, and also deworth your auto.

Rocker Panels Location

Rocker panels are situated in a spot low on the body wright here the eye doesn"t capture, so they may be ignored as soon as washing the automobile. On many type of sporty cars that curve inward at the bottom, carwashes deserve to miss these areas totally. And as soon as OEM plastic or metal trim pieces adorn the automobile, they"re regularly placed over the rocker panels - properly blocking cleaning initiatives that would certainly commonly remove moisture, muck, and corrosive road salt that collect. Severe corrosion is generally the outcome.

All About Rusty Rocker Panels

Back in the 1950s and "60s once the majority of cars in rust belt says occurred rocker panel rot within a few short years, fiberglass repair kits were famous. Strips of fiberglass were soaked in water, then "plastered" onto the jeopardized location to be sanded smooth later. Because virtually all cars of that era had actually sepaprice bodies and frames, rocker panels might be patched because they did not support the weight of the automobile. That was yesterday. Today, the only safe method to repair a rotted rocker panel is to replace it totally. And replacing it effectively indicates cutting ameans the old rusty metal and welding in a complete rocker panel assembly.

Owners of timeless GM vehicles will certainly recognize these sill plate moldings that sit apeak rocker panels on the inside of the door. These, and others choose them, deserve to be culprits given that they trap corrosive moisture too. The truth that they were frequently screwed directly right into holes in the steel rocker panels didn"t aid fight rust either.
Here, an OEM rocker panel plastic trim piece is being removed from a Jeep Grand Cherokee. Because trim pieces favor this have the right to block cleaning of the steel rocker panel behind it, moisture and also salty slush deposits collect tright here and cause corrosion over time.

Formation of Rocker Panel Rust

Except in cases of damages or scrapes, rust on rocker panels virtually constantly creates from the inside out. If the naked eye can check out any type of on the surconfront, it"s a safe bet the metal inside is becoming compromised. And professionals say if you view a hole rusted totally through, the amount of metal that"s been eaten away alengthy surfaces on the inside is many times worse. In brief, the rocker panel is well on its way to disresolving away entirely.

Off-Roading Can Take A Toll On Rocker Panels

Off-roading enthusiasts recognize how grueling trails can be periodically. Bodies of water have the right to hide deep holes, treacherous ruts deserve to appear out of nowhere, and the sturdiest of rocks can transition unexpectedly. Before you know it, the bottom edges of your rocker panels have actually bounced off somepoint hard sufficient to wrinkle and tear steel. Or maybe you sindicate slid into a high area of curbing in poor weather.

If you"ve acquired a rocker panel which has actually been jeopardized in that means, you will certainly want to take into consideration replacing it as shortly as feasible. Significantly jeopardized panels market less structural support over turbulent terrain, are a lot even more susceptible to rust, and they devalue your vehicle by a big margin. Installing a high quality replacement piece is what smart money does, and you must do the very same.

Corroded Rocker Panels Compromise Safety

This photo mirrors an example of rocker panel rust in its worst develop.
The rocker panel of this 1970s BMW 3.0CSi is highlighted in red.

A corroded rocker panel may make it impossible to use your manufacturing facility jack if it’s specially shaped to job-related through fitted jack points, bereason the component of the rocker panel sustaining the jack suggest has lost its stamina. On vehicles via suspensions that attribute rear trailing arms attached to the rocker panels, corrosion deserve to cause a trailing arm to break cost-free. Such an occasion could cause loss of car control either from a wayward rear wheel or seized brakes. Anvarious other risk that originates from rust holes on any lower areas of the auto (including rocker panels as well as floor boards) is exhaust entering the car.

If you bought your vehicle because you worth its security and crashworthiness, remember that the crash ratings it received are based on government crash tests performed on brand-new vehicles without compromised rocker panels. If you suppose to make the vehicle safe, it should be made whole aobtain. The just proper repair to make on a rusty rocker panel is to reduced amethod all the jeopardized steel, and weld in a brand-new one. Unless you have actually sheet-steel welding endure, your best bet is to have the work-related done by a experienced. Of course, once the new piece is in place, the job is not done because that brand-new steel needs to be defended by the appropriate coats of primer, paint, and also undercoating.

Address Any Beginning Stperiods of Rust

On a side note, it’s well worth your time to inspect any drainpipe holes located in rocker panel locations on a regular basis. Clean out any gunk that’s collected inside them to proccasion moisture buildup which leads to corrosion. And if you find any type of minor surchallenge rust beginning to form in surprise locations, dry the locations out thoroughly, scrub things dvery own to the metal with a wire brush (or tapered narrowhead brush), and use some rust inhibitor.

We market a choice of wire scrub brushes right for removing surchallenge rust.

Specific Rocker Panel Parts We Offer

Whether you"ve acquired a work-related truck, off-roader, or restorable classical, we stock top quality replacement finish rocker panels from trusted manufacturers that specialize in producing OEM-high quality body components at lower-than-OEM prices. We additionally sell various other related parts such as dog legs and end caps, which join different ends of the rocker panel to the rest of the auto.

Dog Legs


In the people of rocker panels, a “dog leg” is an L-shaped reinforcement piece uncovered on a 4-door car behind the rear door and also in front of the rear wheel opening. It joins the horizontal rocker panel to the vehicle’s quarter panel.

End Caps


End caps are other forms of pieces that sign up with the horizontal rocker panel section to the remainder of the automobile. While finish caps are typically positioned at the front of the rocker panel, some vehicles usage them at the rear as well.

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Rocker Panel Patches


What is a rocker panel patch? These pieces are partial sections of the horizontal rocker panel. They’re useful once corrosion has actually compromised just a small area, and the whole rocker panel does not should be cut out and reinserted. We’ve obtained patch pieces from Goodmark, Sherguy, Spectra Premium, and more.


To assist guide you with the Rocker Panels area of our website, we have collection it as much as provide you the particular options for your year, make and also model ride. Once your vehicle"s indevelopment is gave, you"ll instantly check out all the rocker panels and also related items that fit.

To sum it up, replacing jeopardized rocker panels restores vehicle crashworthiness, rises safety and security, and also offers you tranquility of mind that your vehicle’s backbone is as strong as ever before. We’re glad to aid via any type of questions you may have actually concerning rocker panels, so provide us a speak to salso days a week!