Light undercoating, surface rust prevention

[dhcomp]

So, as I announced in the Lounge, i'm moving to the Truckee area.

I'll be commuting to Reno/Sparks in my 335xi, and driving the burb around town.

My cars are clean, with just a bit of surface rust on the frame of the burb.

What's my best way to avoid corrosion over the winters?

The burb will most likely live outside in the snow , and the BMW will be garaged.

I'd really like to keep the burb corrosion to a minimum.

Any light undercoatings worth anything? Even considered dousing the frame with WD40 when its sitting for a week or more at a time.

Truthfully, I'm more concerned about the Burb. The bmw will be driven 100miles a day commuting, and will probably be sold in 2 yrs before the warranty runs out. So, ill do my best to keep it nice, but its more or less disposable.

Tips?

 

[76k5blazerr]

Rust Bullet. It's a paint that's very easy to use, little to no prep work, and it works, lasts 10 years or so. I used it on my k5, still holding up great. There's even a product review on it in that section of this forum. It's good stuff, I'd say it's the best if not one of the best out there as far as rust proofing goes.

 

[dhcomp]

Wonder what it would cost to have someone apply it.

 

[Deuling]

I prefer an oil type product. You can't get all the undercoatings up in all the crevices etc. But oil you can apply all over. The most rust free spots on most of these are where the engine/trans/tcases leak and fling oil all over. Then it gets mixed with dirt and dust and makes a nice caked on coating.

It's ugly but it's best thing imo.

 

[Mikey von]

Not sure what they use up hwy 80, but in my parts of N. CA, they use cinders instead of salt. Not that it answers your question, but might look into it and save some grief.

 

[ryoken]

the best prevention is a proper topcoat system, but for existing undercarriages, what Adam said..

RB and POR15 aren't preventers, they are just encapsulators for something that's already rusted..

 

[skunked]

How long will you live up there?

I was up there for a couple years and didn't have any noticeable increased rust. I gave the frame a good wash at the local taco wash every other week or so. And FWIW they don't use salt like they use to....

 

[76k5blazerr]

I'm still gonna vote for the RB, it's easy to apply, not to thick like an undercoating so you can get it in those hard to get to places (I know from experience) and it's fairly inexpensive as far as undercoating choices go, and from what I've seen on my truck it does prevent rust as well as stop it in its tracks because I painted my new bare metal floor pans with it and they still look like they were painted recently. It's worth checking out.

 

[ryoken]

I'm very familiar with it.. I was using it and por back in the 90's on boat trannies.. long before intraweb fame.. it is, what it is, an encapsulator..

 

[dhcomp]

Thanks guys.

I was thinking an oil type product too.

I plan to live up there for at least a few years, if not permanently.

Just a few winters back and forth skiing has put a light coat of surface rust over everything, just looking to keep it from getting worse.

Something oil based i could put in a sprayer, and go to town on the underside would be best. Time is getting scarce. Thanks!

 

[Deuling]

Just fyi wd40 doesn't last very long imo.

Something a bit stickier/thicker would be better.

 

[diesel4me]

I've seen some fleets of Semi's locally that contractors own,they keep their trucks "forever" and they use the oil drained from the diesel engines as undercoating...the soot makes it cling good and resist washing off,and the frames on some of their 1970's Macks look like new still,zero scale or rust--slimy and sooty yes,but not rusted!..

They also paint their trucks with Imron,some were painted 25 years ago and still shine like it was last year..they do wax them often too though,and steam clean them..

Some gas stations here used to spray the drain oil on a customers car when the did oil changes..a friend of mine bought a '67 Impala from his grandmother who had her oil changed at such a place--the underside of that car is amazing..oily and slimy,but still like new..

 

[dhcomp]

Not going to lie, i thought about doing that.

But, don't want a dripping mess. Not sure I could get it to spray fine enough to not drip.

 

[diesel4me]

The contractor's trucks do a lot of gravel hauling,so right after they douche the frame with the drain oil,they go for a ride around the gravel pit or a dirt road,the dust clings to the oil and then they park the truck for awhile to let and excess come off...a trip down a highway at 70 mph would take any extra oil off quickly too...

You could park over an old tarp or blanket and let the excess drip onto that..

Some off road enthusiasts here spray boiled linseed oil on their undercarriages,it keeps mud from sticking,lets it wash off easier, and prevents rusting pretty good too--it dries to a coating rather than staying liquid,that might be a cheaper and more environmentally friendly option..