# Chassis and Underbody Respray: Cost, Hours and Process in Hacienda Heights Chassis and underbody respray refinishes frame rails, crossmembers, suspension brackets, steps, generator trays and underbody surfaces after cleaning and rust treatment. It is protective coating work rather than cosmetic work, and the preparation determines whether it lasts or simply hides what is happening underneath. ## Specifications - Price band: $500 to $3,500 - Shop hours: 3 to 16 hours - Turnaround tier: Light cosmetic - Insurance billable: yes - Parts lead time: Chassis coatings and stone guard in stock, 3 to 7 business days for a specialty high build or high temperature coating - OEM brands: PPG, Axalta, Sherwin-Williams, 3M ## Preparation decides whether this lasts Coating over rust does not stop rust. It hides it, and it hides it while it keeps going, which is worse than leaving it visible. That is the entire argument for why an underbody job is mostly preparation. Preparation means degreasing first, because road film and oil residue defeat any coating adhesion. Then mechanical removal: wire wheel, needle scaler or targeted media blasting depending on access and how much scale is present. Loose scale has to come off entirely, and where it cannot be reached, the honest statement in the estimate is that the area is limited rather than pretending it was addressed. Where residual oxidation remains in pits, a rust converter or an epoxy primer formulated for tightly adhered rust goes on before the topcoat. That choice matters and it depends on what is actually there. A converter over loose scale is theater. Epoxy primer over a clean, tightly oxidized surface is real protection. ## What goes on top and why the choice differs by area Different underbody surfaces have different jobs, so they get different coatings. Frame rails and crossmembers get a direct to metal epoxy primer and a chassis grade topcoat, chosen for chemical resistance and adhesion rather than for gloss. Areas that see stone impact, meaning the lower front, the region behind each wheel and the leading edges of underbody panels, get a high build stone guard that stays slightly resilient so an impact deforms it rather than chipping it. Suspension components and brackets that see heat cycling get coatings rated for it. Exposed lower sidewall areas above the underbody are a paint job rather than a chassis job, and stone guard applied to a visible lower panel is a deliberate aesthetic and functional decision that gets discussed rather than assumed. Many owners want it on a coach that tows or runs desert highway miles and many specifically do not. What we do not do is blanket spray. Masking matters as much here as in the booth: brake components, driveline, exhaust surfaces, vent openings, wiring harnesses, tank fittings and anything that has to be serviced later all get protected. An underbody coating sprayed over a fitting somebody will need to open is a repair bill for the next technician. - Degrease, then mechanical removal of loose scale by wheel, scaler or targeted blasting - Rust converter or epoxy primer selected to what is actually present - Direct to metal epoxy primer on cleaned steel - Chassis grade topcoat on frame rails and crossmembers - High build stone guard on impact zones behind wheels and at the lower front - Heat rated coatings on components that cycle hot - Full masking of brake, driveline, exhaust, harness and serviceable fittings ## Cost, hours and the collision case The band on this page covers three to 16 hours at the posted body and paint rate of $210, and the honest driver of where you land is access. A tandem axle travel trailer with an open frame is fast. A Class A with underbody panels, insulation, tanks, plumbing runs and a generator bay in the way takes substantially longer for the same square footage because everything has to be worked around or removed. Body supplies bill at $5 per body hour and paint supplies at $55 per paint hour, and on underbody work the split leans toward body hours because so much of the job is preparation rather than spraying. The most common version of this job here is post collision. When a frame section, a crossmember or a bracket has been repaired or replaced, that steel leaves the fabrication bay bare, and coating it is part of returning the vehicle to pre loss condition. That makes it a legitimate line on a claim, and we write it as one with photographs of the bare steel and the finished coating. Preventive undercoating on a coach with no damage is owner pay work and we are clear about which category a given job falls into. ## Not included - We do not spray underbody coatings at a customer location. Overspray control, ventilation and a lift are required. - Structural rust that has reduced section thickness is a welding and fabrication scope, not a coating scope. - Engine, transmission and drivetrain service are outside what this facility performs. Coating work is exterior surface work only. ## Questions **Can you treat surface rust and repaint my RV frame?** Yes, and the treatment is most of the work. Degreasing, mechanical removal of loose scale, then either a rust converter or an epoxy primer formulated for tightly adhered oxidation, then a chassis grade topcoat. Where structural rust has actually reduced section thickness, that is a welding and fabrication scope and gets addressed before any coating goes on. **Is undercoating worth it on a coach in Southern California?** The road salt argument does not apply here, so the value is different. What matters locally is stone impact and coastal moisture. Stone guard on the lower front and behind the wheels is genuinely useful on a coach that runs highway or desert miles. Blanket undercoating on a dry climate coach is a lower priority than most sellers of it suggest. **Will insurance cover underbody refinishing?** Where a covered event damaged the area, yes. Refinishing bare steel after a frame section, crossmember or bracket has been repaired or replaced is part of returning the vehicle to pre loss condition and is a recognized line item. Preventive coating on an undamaged coach is owner pay, and we identify which category applies in the estimate. **How much does an underbody respray cost?** Three to 16 hours at $210 per hour covers the band on this page, plus body supplies at $5 per body hour and paint supplies at $55 per paint hour. Access drives the number more than area does. An open trailer frame is quick. A Class A with underbody panels, tanks, plumbing and a generator bay in the way is the top of the band. --- Source: https://ocrv.club/rv-paint-shop/chassis-and-underbody-respray OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887 Phone (949) 799-3387. Email info@ocrvcenter.com. Serving Hacienda Heights and the surrounding area. 18.4 miles, 24 to 38 minutes via SR-60 west to Fullerton Rd, then south to La Palma Ave. In shop work only. All estimates are priced and credited against an authorized repair.