How to protect from rust under the car?

CelticRunner

CelticRunner

Member
Bought my 06 4Runner used w/ 62k miles in August, been lurking for a while but now i have a question Which concerns me.

What can I do to ensure the under body of my car does not get all rusted away?

I used to drive a jeep cherokee and loved it, but one drive my exhaust pipe fell off out of the blue. I knew it wanst exactly attached to the muffler, but the U bolt that held it to the car finally rusted through. Upon further investigation it seemed much of the under body was rusting and Did not look good at all. Im sure the mechanic would have said something if it was real serious though.


BTW, Im not really a mechanical type of guy who takes apart the engine, in fact most of the mods ive seen look cool or interesting but way above my level (even electrical ones).

any ideas or help would be great. even it is just to get under there somehow and clean it.
 
Register to hide this ad
Welcome to the forums. Yes you can bump your own threads. I don't know have any suggestions for you though :(. I just try not to think about it.
 
Rust Check does an under body spraying that is like an oily gel. I got mine done when it was still hot outside, and it eventually made the stuff on the under body slightly greasy to the touch, but overall dry and protected.

Other than that, I just try to get a car wash and hose things off whenever the weather changes from freezing and salty to warmer and salty.
 
If you plan on undercoating, it's important to NOT get a rubber based coating.

Since your truck has seen some winters, if you use a rubber undercoating, it will trap the rust you have and cause it to eat away at the frame from under the rubber. The rubber undercoating may be a good idea to apply to a brand new truck, but not one that has already been subjected to the elements.

Most mechanics should offer some type of oil based undercoating, you'll want to make sure your truck is clean underneath before you get it applied. It's better to apply it before the winter hits.
 
thanks for all the help, i'll look into the oil based undercoats... but i'll try to avoid what you've got goin on there Mr. Leary ;)
 
Last edited:
ironhippy said:
If you plan on undercoating, it's important to NOT get a rubber based coating.

Since your truck has seen some winters, if you use a rubber undercoating, it will trap the rust you have and cause it to eat away at the frame from under the rubber. The rubber undercoating may be a good idea to apply to a brand new truck, but not one that has already been subjected to the elements.

Most mechanics should offer some type of oil based undercoating, you'll want to make sure your truck is clean underneath before you get it applied. It's better to apply it before the winter hits.
Click to expand...

Yup, that's the truth. I actually went through the trouble of wire brushing underneath to remove paint and rust flakes (it was as messy as it sounds), and then getting underneath with a hose and cleaning everything off. After the oil application at the shop I got a few spray cans of the same product just to do touch ups on the hard to reach places he missed, and around little bolts and stuff in the engine compartment, etc.

Things such as my rear axle and such are still a little surface rusty of course, but they are stable and not rusting or flaking more. Every time I get a car wash now in the winter, afterward the parts are shiny but dry feeling, kind of like a well oiled cast-iron frying pan would be.

I'm tempted to find a steam cleaning system for underneath and to get that done next summer before applying Rust Check again.
 
Spray Paint

I've been thinking about this a bit lately. On my '92, I've had a couple holes in my muffler starting 2 years ago. Since it's back from the cat, it shouldn't affect emissions and just makes the V6 sound even throatier, so I haven't bothered with replacing it until now. The stock cat was conveniently stolen 4 years ago, and the aftermarket replacement looks fine. And taking down the muffler piping, it looks mostly ok too, with a bit of rust at the end as expected. Hot steam comes out of that all the time as part of combustion.

When buying my '98 I crawled around under the truck, and it looked fairly well. But with winter driving including salt in some areas, I wouldn't mind some extra protection. I was thinking about some rustoleum spray paint, particularly the high temp stuff that I use on the stovepipe and BBQ that says it's good to 1400 F and is for putting over rusty stuff.

It won't necessarily cure the exhaust system completely as some of the rust is coming from the inside, out. But it should help a lot.

That said, there's a couple other things I might try (sacrificial anode?, the "Rust Check" stuff, or just washing the undercarriage weekly in the winter).
 
Mr. Leary said:
My Land Cruiser has an oil leak. Its done a great job of undercoating the truck. :cowboy:
Click to expand...

hey, me too. What series cruiser?

To the OP. I wash the undercarriage at LEAST once a month. Try to get all the nooks and crannies. Pressure isn't needed. Just a good flushing. I pull mine into the garage and give it a good douching. My past 4runner was purchased with some surface rust. It really did a good job of slowing it down. There are some good oil based systems out there to deter it but you cant stop it completely.
 
I agree with the rubber coating. I bought my 2011 TE brand new and it was delivered to the dealership the day that I bought it with 2 miles on it. I had the coating done underneath before I drove it off of the dealership. It's definitely worth it.
 
I use Fluid Film in the spray can. I have a small can with a brush in it too which works well for smaller and more precise applications. The spray comes out heavy so I use a cheap paint brush to spread it and get into all the crevices. One can should be able to cover everything if you back brush it.
 
Mr. Leary said:
My Land Cruiser has an oil leak. Its done a great job of undercoating the truck. :cowboy:
Click to expand...

^ :lol: ^

my solution would be to move away from states that have rust problems...

Your poor 4runner deserves better than to live in a state that will slowly kill it! :sobbing:
Save your 4runner, move away!

ok, so its not the most economical plan, but its one of the only sure fire ways to keep your vehicle from rusting.
 
I have always used spray paint. Rustoliem (sp?). If you keep a coat of paint on it won't rust. On my jeep it is easy. It is lifted high enough so I can easily crawl under it. I am new to the Toyota a world. Last night I was under the Toyota and painted about the whole frame. There was a little surface rust. When It warms up I will spray wash the underside and get up there with a wire brush and remove what rust I can and the paint with Rustoliem.

This isn't a onetime fix, on my jeep I do it every time I come back from wheeling, the Toyota it I will probably do at the end of winter and end of fall. Periodically I will power wash underneath to help keep the underside clean.
 
You may want to consider POR-15 products to protect areas that are already rusted and to protect the underside of your truck. That's what I'm planning to use this coming summer.
 
well just my .02 worth. I went to walmart a while back and bought about 8 cans of the $4.00 spray undercoating. Since I have no rust and the truck is 6yrs old I figured it would be a good time to reapply and add to different areas under the vehicle.
I have done all the factory skids, entire frame, wheel wells, rear diff and rear axle.
Basically, anything thats metal under the vehicle. If you do have some rust, just knock it off, seal it and the you should be able to coat with what ever you like.
 
And make sure you wear protective clothing when you use POR-15. Last September I cleaned off and repainted the a-frame of our Airstream with POR-15. I got a little careless and got the stuff on my arms. It was there for several weeks...
 
I have used POR15 and it can rub off if you are off roading, and still need to be touched up.

If you don't off road or scrape your frame it will probably last a long time.
 
You must log in or register to reply here.

Members online

Total: 1,129 (members: 6, guests: 1,123)

Forum statistics

Threads
278,312
Messages
3,554,085
Members
248,016
Latest member
Advally Service

Share this page

Trending content

Back
Top