Family owned since 2020 · Port Huron, MI
Michigan eats trucks. Yours doesn't have to be one.
FLUID FILM® rust proofing sprayed where the salt actually sits — frame, rockers and cavities. Prices by vehicle size are below. Tell us the vehicle and you get a real number back, usually the same day.
Seven days a week, by appointment. Can't stay? There's a key drop box.
- most vehicles, start to finish
- ~1 hrmost vehicles, start to finish
- creeps into seams, never cracks
- FLUID FILM®creeps into seams, never cracks
- by appointment · key drop box
- 7 days · 9 AM – 10 PMby appointment · key drop box
What we do
Straight prices, by vehicle size
No call-for-pricing. The menu is below; tell us the vehicle and what shape it's in and you get a confirmed number back, usually the same day. Commercial work and trailers are quoted per unit.
Advertised prices · pay at the shop
Full underbody rust protection
What the job coversFLUID FILM® into the frame rails, rockers, cavities, behind the taillights and the bed panels — the whole underside, not just what shows. Priced by vehicle size.
- Small vehicle$350Cars, hatchbacks, compact SUVs.
- Mid-size / full-size$400Pickups, full-size SUVs, vans, mid-size crossovers.
from $350Get a quote →Annual touch-up
The yearly pass for a vehicle we have already protected — renewed every autumn before the salt goes down.
$200Get a quote →Descaling
Why it works over rustHeavy scale and flaking rust knocked off the frame before the film goes on. Billed by the hour.
$150 per hourGet a quote →Wash, degrease & frame flush
The underside washed, degreased and the frame flushed out — on its own, or before a full protection job on a dirty vehicle.
$150Get a quote →
Quoted per unit · contact us
Commercial & fleet vehicles
Fleets · work trucksWork vans, pickups, service bodies, plow trucks. Quoted per unit — and five or more get the fleet deal.
Fleet deal: five-vehicle minimum, the sixth vehicle is free.
Contact usGet a quote →Trailer, RV or equipment
Trailers & farm equipmentTrailers and implements rust from the inside of the frame rails out — and sit outside all year. Quoted by the job.
Contact usGet a quote →
Tell us the vehicle and what shape it's in, or call (810) 357-3023.
The product
Why FLUID FILM® and not paint
It never fully hardens
A hard coating cracks, water gets under it, and the rust is sealed in. FLUID FILM stays active.
It creeps into the seams
After it's sprayed it keeps migrating into cavities and behind panels — where salt actually sits.
It goes over existing rust
No stripping first. It stops the spread, and a fresh pass every autumn keeps a frame alive for years.
Out of the bay
Before, and an hour later
Real vehicles that came through the bay on Lapeer Road. The rust ones are what people drive in with. The dark ones are an hour later.
On the rack
Before
Before
After
BeforeAfter
Customer
BeforeCustomer
After
Before
After
Customer
Trailer
CustomerHow a visit works
Drop it off, drive it out
Send the vehicle over
Year, make and model, and a photo of the underside if you have one. You get a real number back, usually the same day.
Pick a time
Seven days a week, 9 AM to 10 PM, by appointment — so your vehicle is not sitting in a queue.
Drop it off
Stay and wait, or drop the keys in the box and go. Most jobs are about an hour on the rack.
Back on the road
Pay at the counter, go easy on it for a day, and come back next fall for the touch-up.
Questions
Questions people ask before they book
- How long does undercoating take at Underline Undercoating?
- About an hour for most vehicles, start to finish. You can wait, or drop the keys in the box and come back. The shop is at 2498 Lapeer Rd in Port Huron, Michigan, 7 days · 9 AM – 10 PM, by appointment only.
- How much does rust proofing cost in Port Huron?
- The prices are on this page: full underbody protection is priced by vehicle size, the annual touch-up is a flat price, descaling is billed by the hour, and a wash, degrease and frame flush has its own price. Commercial vehicles and trailers are quoted per unit — send the vehicle through the quote form and you have a confirmed number, usually the same day.
- Do I have to book online?
- No — nothing books online. Send a quote request or call (810) 357-3023, we confirm the price, and we set a time that suits you. Seven days a week, 9 AM to 10 PM, by appointment only.
- Is rust proofing the same as undercoating?
- Here, yes — it is the same hour of work. Rust proofing is what the job does; undercoating is where it goes. We spray FLUID FILM® into the frame rails, rocker panels, cavities and behind the panels, not just the underside you can see from the floor.
- How often should a vehicle be undercoated in Michigan?
- Once a year, ideally in the autumn before the salt goes down. FLUID FILM® works all winter and gets renewed every fall; the annual touch-up is the yearly pass for a vehicle we have already done.
- Can you undercoat a vehicle that already has rust?
- Yes. FLUID FILM® goes straight over surface rust and stops it spreading. Heavy scale gets knocked off first — that is the descaling service, billed by the hour — and then the film goes on. If the frame is badly gone, send a photo through the quote form and we will tell you honestly whether it is worth doing.
- What if I can't stay while it's done, or can't come during the day?
- Use the key drop box. Drop the vehicle and the keys at the shop, we do the job, and you collect it when it suits you. Hours run 9 AM to 10 PM, seven days, by appointment.
Something else on your mind?
Ask Rick →Find us
2498 Lapeer Rd, Port Huron
- The shop
- 2498 Lapeer Rd, Port Huron, MI, 48060 · Directions
- Hours
- 7 days · 9 AM – 10 PM · by appointment only · key drop box for drop-off
- Talk to Rick
- (810) 357-3023 · family owned since 2020
Stop it before it starts.
Tell us the vehicle and when you could drop it — most jobs are done the same day.