Ziebart or ?????

[30calflash]

Oil, ATF and fluid film will most likely wash off after a time. Many rustproof materials were meant to adhere to the underside for years, but inside doors and other places would remain soft and sticky. The soft sticky material wasn't used underneath for washing away was a real issue.

If it's done right it should help but many manufacturers do a good job and having holes drilled causing broken paint and undercoats to be damaged messes that idea up. Best to have the interior trim panels removed for gaining access to inside of doors, splashliners removed to access fender openings, etc. In other words lots of work. ($$$)

Also best to do when the vehicle is new, you don't want to seal in moisture, dirt and mud as it will never dry out and has only one way to go, thru metal.

Subframes and suspension parts are bad as they don't clean the surface after welding brackets and such, just prime or paint over them. The first place you see rust on those parts are where the have been welded and that is why.

A friend has a Toyota pick up in Vt, lots of salt used there. He was adamant about cleaning the underside regularly after storm clean up and used this vehicle daily. When Toyota had the recall for bad, rusted frames he brought his in and they didn't replace it as it was solid due to the extra time he spent cleaning it.

My boss has a mid 80's Wrangler for plowing, built from a couple wrecked units. When it was put together he had the frame sandblasted as best he could and epoxy primed and painted. He washes it after a storm and will do so if it storms a few times a week. About once a month it goes on the lift and gets crusty spots scraped, either a rust conversion paint touch up or he used to use old axle joint grease applied with a brush. It seemed to work as it's been plowing for over 30 years and is now a back up to a newer Jeep.

So, I guess it comes down to being pro active on maintenance and rust removal on a regular basis for something you wish to keep in the family especially now that 4wd trucks can cost as much as a small house. Or even a decent car for that matter.

[ascast]

I like Ziebart but think it is far better on a new vehicle. Anything that has been out a year or more, your are relying on the workers as much or more than the product. Anything you can do to get the salt off is beneficial. Here in CNY it is not uncommon to see car with small cat holes after 5 years; trucks with frames rotted out. If I had a new ride, it would get an undercoat.

[uscra112]

Factoid: The original Carl Ziebart formula was declared persona non grata by the EPA in the late '70s, (if I remember right) and it hasn't been the same since.

[Bird]

I have been using Finnegans Waxoyl since the 70's and it does help a lot. I use it on my restorations where the car is taken down to every last nut and bolt, and its easy to get into the door panels and frames. It helped with the UK weather, but being in california now the climate is more car friendly.
The waxoyl does have alox in it.

[MaryB]

When I bought my 2017 Ford Escape the dealer said they d not rust proof anymore. The factory applied coatings are just as good and applying something over them can void the warranty!

[BucketBack]

Sure it'll help.
But not driving it in the winter when they salt the roads up there is the biggie to preserve it.

When I was stationed up on the East coast,
I was amazed to see a few cars 2-3 years old and the fenders were flapping from being rusted out.

Guys from up there in the snow belt talked of people having a old, beat up 'winter beater' to drive when the roads were salted.
They didn't drive their newer car at all until the weather cleared and the roads had washed them selves off.

Here, if you drive on or around the coast the same thing happens.
You also see car washes that spray as much under your car to wash the salt spray off as they spray on the outside.

Yup, just bought a ArKansas 2003 envoy that will be stored this winter. I will be spraying the underside with undercoating before storage.

[TimD]

I have had two new cars done with Ziebart. I think it helps if done well. Their quality went down over time and after having issues with two locations I gave up on them. I switched to Rust Check for my latest car, so far I think it is better. All were kept in an unheated garage which helps. My rust issues have been due to chips and scratches in the paint, never had an issue with the undercarriage.

[fecmech]

I do my own oil changes so I get a pretty good view of the underside of my car. The '14 Honda CRV that I own looks well protected as it comes from the factory as does my wife's 2007 Rav4. Neither car has any body rust and I live in the Buffalo NY area. I did have to replace the muffler on the Rav at the 10 year mark.