RV and Commercial Vehicle Body Repair

Three materials, three completely different sets of rules. Most large vehicles carry all three.

Steel behaves the way body shops expect. It work hardens when deformed, so a dent has more strength than the surrounding metal and has to be worked from the outside edge of the damage inward. It can be shrunk with heat and stretched with a hammer and dolly. It rusts, so any repair has to restore the coating system underneath as well as on top.

Aluminum does not work harden the same way and it does not tolerate repeated working. Bend it back and forth twice and it cracks. It also requires isolation from steel, because dissimilar metals in contact with an electrolyte, which is what coastal air is, produce galvanic corrosion at the joint. Aluminum panel work is done with dedicated tools kept away from steel, because steel particles embedded in aluminum start corrosion sites. On riveted units, Airstream and similar, replacement panels are set with new rivets and the sealant behind the seam matters as much as the fastener. Aluminum skin and sidewall replacement runs $2,500 to $25,000 across 16 to 120 hours.

Fiberglass and composite do not dent, they crack and they delaminate. There is no pulling a fiberglass panel back into shape. The repair is laminate replacement, which is covered under fiberglass repair.

Deciding which one you are looking at is not always obvious on a painted surface. A magnet answers steel versus not-steel. Tap tone and edge inspection separate aluminum from composite.

The dividing line is labor hours against part cost plus the condition of the surrounding material.

Bumpers and covers

Steel and aluminum bumpers on trucks and coaches are frequently straightened and refinished. Plastic covers on vans are repaired when the damage is a tear or a scuff and replaced when mounting tabs are broken, because a cover that will not clip in properly never sits right.

Fenders and quarter panels

Repaired when the damage is accessible from behind and the metal is not stretched past recovery. Replaced when the panel is creased across a body line, because a body line is a stiffener and reforming one to factory shape by hand is slower and less reliable than fitting a new panel.

Compartment and baggage doors

Usually replaced. They are lightweight laminated or aluminum assemblies and the frames distort easily. Repair runs $200 to $1,800 across 1 to 10 hours.

Entry doors

Repaired when the shell is sound and the problem is the frame, hinge or latch. Replaced when the door skin has separated from its core. Entry, baggage and compartment door work runs $400 to $4,500.

Sidewall skin

Replaced in full sheets to a seam. Patching a skin leaves a joint that shows through paint and creates a new water path.

The sub services under this line are dent removal and repair, panel replacement, bumper repair and replacement and fender and quarter panel repair.

Glass on large vehicles is a body operation because the frame it sits in is a body component. Window and frame reseal and replacement runs $250 to $3,500 across 1 to 14 hours, covering Hehr, A and E, and Kinro frames among others.

The failure most owners report is a leak, and the cause is usually the butyl tape behind the frame rather than the seal around the glass. Butyl has a service life. It hardens, loses its ability to conform, and lets water past at the corners where the frame flange is least flat. Resealing means pulling the window, cleaning both surfaces completely, and setting it in new butyl with the fasteners drawn in sequence rather than one at a time, so the frame seats evenly.

Windshields on Class A coaches are their own operation. One-piece and two-piece Class A windshields run $2,500 to $7,500 across 6 to 18 hours, and the labor is high because the glass is large, heavy, and set in a gasket that has to be worked into a frame with the glass supported the whole time. Two-piece units add a center divider that has to seal against both panes.

Foggy dual-pane windows are a seal failure between the panes, and the fix is either resealing the unit or replacing the glass pack, depending on the manufacturer and the availability.

Because paint is a magnifier. A surface that looks straight in primer will show every imperfection once it has gloss on it, and gloss reflects a line that bends where the surface bends.

Straightness is checked three ways before anything is sealed. First, a guide coat: a contrasting dust applied over the primer and sanded off with a long block, so any low spot retains the guide coat and any high spot cuts through. Second, reflection: a fluorescent tube or a straightedge reflected across the panel at a shallow angle, which reveals waves the hand cannot feel. Third, feel: a bare hand dragged slowly across the surface picks up transitions a gauge misses.

Filler thickness matters too. Body filler is meant to fill millimeters, not centimeters. Thick filler cracks, shrinks and telegraphs a ghost line where its edge is, particularly after a hot Southern California summer heats the panel and the filler expands at a different rate than the substrate. If a repair needs more filler than that, the metal or laminate underneath needs more work.

Once the surface is right the job hands off to paint and refinishing. Both lines sit under paint and body services, and the estimate splits the hours because body labor and paint labor bill against different material calculations, $5 per body hour and $55 per paint hour respectively. See the price sheet.