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We purchased a 2010 Toyota Camry two months ago and had it undercoated by the dealer. Within days there were spots on the garage floor from dripping undercoating, not all over, just in certain areas. The undercoating outside these areas appeared to have dried as expected. The dripping has stopped, but areas that were originally wet are still wet. The dealer and the undercoating manufacturer say the problem is where the undercoating is over seam sealer. Dealer says they have not seen this before and the undercoating manufacturer says they have seen it on some Toyotas. Both said we should just keep waiting for it to dry. Now they are suggesting that the dealer wipe off the wet undercoating. Seems to me there must have been a reaction between the seam sealer and undercoating with one or both being damaged. Any comments or suggestions?

I didn’t know that they still undercoated cars. Modern cars don’t need this. If this undercoat job was sold with a rust-out warranty, be certain to hold the dealer to the terms of the warranty and keep up your end by having the undercarriage checked by the dealer at regular intervals.

I can’t imagine it being a reaction between the undercoating and the seam sealer. I would press the dealer for a solution to the dripping undercoat besides wiping it off.

This sounds like reason number 4,068,746 not to buy those “extras” car dealerships try to sell you.

Whether it is “clear coat,” “fabric protection,” or “undercoating,” You don’t need any of these things. You should ask for a full refund.

I was surprised they still sell undercoating too. Back in the days of 8-tracks and Pintos, the big name in undercoating was Ziebart. I haven’t seen them around in years. The cars that went through this seemed to rust just as quickly. Often the drain holes would get plugged with the undercoating goo and make matters worse. And if the installer sprayed any on the window tracks, they would get all screwed up. If you wanted something extra, you should have gone for the optional roof rack or fabric protection. They’re just as usless, but at least your windows would still work!

Did You Verify That The Add-On Rust-Proofing Won’t Void The Manufacturer’s Body Rust/Corrosion Warranty?

I’d be more concerned with that than wet or dripping undercoating. Read your car’s warranty information and do your own homework. Don’t take the dealer’s word. If it voids your standard warranty, now is the time to pursue this with the dealer and reach a settlement. They could be gone or have changed hands by the time you need to make a claim.

Also, if that stuff stays wet there’s a chance it will wash off in heavy rain or adverse conditions. I agree with Whitey. Get your money back.


There’s a Ziebart here in Marion still, but they’re more a window tinting and sunroof installer along with running boards and remote starter instalations

CSA–I was thinking the same thing.
All modern cars come with excellent rust-proofing right from the factory, and they also come with warranty coverage against “rust-through” of body panels. This unnecesary “schmutz” that was smeared on the underside of the car very likely will void the car manufacturer’s rust-through warranty.

This is a classic case of shooting yourself in the foot. At least if the OP demands a refund, he/she will not have spent any money on voiding that part of their warranty coverage.

looks like they may have put on right after washing the car. and it never dried or they put it on too wet. and even though the car is new. if you live in an area where there is a lot of snow, or near the ocean, then having it on is a little extra protection form the salt which does eat thru anything.

Just to echo everyone else concern, rust proofing is not a one time treatment and any attempt to do so can cause more problems then intended. Clogging drain holes and using a substance that does harden is a concern. A thin oil based treatment done regularly is helpful as well as frequent washing. That it does drip is a good sign. It appears to be an thin oil based (motor oil is good) and as such will drip. Hope you didn’t pay much for it.
Seldom do cars rust “underneath”. They rust through seams where panels join and w/o proper drainage. You could do better than they with 15 minutes of your time, a garden sprayer, and a quart of motor oil. That’s needed only if you live or travel in road salted areas or near ocean frontage.
Don’t feel alone. Car dealers make much of their profits on parts and service that customers don’t often need. Don’t believe dealer comments on not seeing it before. They seldom see any “mistakes” they make. I don’t personally feel there is a problem with the dripping. Just don’t expect long term miracles from the treatment.
Car makers could use steel with a minimum of chromium added (even less than the 11% for stainless) as well as other treatments to minimize rust problems for many years at minimal expense. Why would they bother. Rust is their friend.
They do only what’s necessary to stay ahead of the competition…but not too far. Car body design with proper drainage and ventilation does as much to prevent rust as many so called factory “treatments” they advertise.