Rustproofing/ Undercoating new vehicle?

Bought a new 2012 GMC Sierra 4X4 two weeks ago. One priority was to have it rustproofed before it left the dealership... but no, they said it would void the factory corrosion warranty and their dealership simply doesn't do it anymore and strongly recommended not having it applied by aftermarket. What gives?

I musta been under a rock for the last ten years since I bought my last new truck, an '02 Silverado, because I haven't heard this before. I passed on the protection deal then, the body held up great but the frame started rusting after a few years and turned to tree bark looking E36 M3 after 7 years, the rear bumper finally poked through recently too. Oh, and more tree barked brake and trans lines and oil cooler, ugh. The Chevy dealer back then offered a waxy/ translucent looking goo as compared to anything rubberized.

Just turned 100 miles yesterday so before it gets too dirty underneath for any application I'd like to know... yes/ no/ opinions/ options?

Googles provided little insight, time to kick it around w/ the experts.

TIA

Never heard of that.

We had my wife's 2010 Golf Wagon done about 1 1/2 months after picking it up.

I won't buy another new car without doing it. I won't let them drill holes though. I did the package that they only use the existing holes.

See, they install that True Coat at the factory.

That is true. Back in the '90's when I was with GM, adding an aftermarket undercoat or corrosion prevention package voided the factory rust perforation warranty. Still does.

Curmudgeon wrote: That is true. Back in the '90's when I was with GM, adding an aftermarket undercoat or corrosion prevention package voided the factory rust perforation warranty. Still does.

thnx Curmudgeon

but would you still have it done regardless? say Ziebart?

I recently did my truck myself using Fluid Film. I plan on re-applying it once a year.

http://www.fluid-film.com/

Waxoyl is another product that's popular for this kind of use, but it was more expensive, so I went with Fluid Film.

I wouldn't let Ziebart touch anything I own. The local one in Rochester is a known hack shop.

The only rust proofing that really works is the oil/parafin based stuff. The oil spray coats everything, and as an added bonus, soaks in so bolts won't be a PITA to remove. I've seen a guys 98 Chevy truck with ZERO rust on it that he's had oil sprayed every year. The brake lines still look new. Granted, it's only got 50k on it, but he leaves it outside 24/7. A couple brands off the top of my head are Rust Stop and Rust Check. Being GRM, an alternative would be to put some thick oil in a spray bottle and soak your truck down once a year.

Some higher end cars come rust proofed from the factory so the voiding the warranty is a bunch of BS. I think they want your car to rust out after the warranty so you'll buy a new one. Read your warranty, they only cover rust THROUGH which almost never happens. Most rust proofing has a rust warranty that comes along with it that's better than the factory anyway. I had a new Ford that was rusting along the door skin after 2 years and Ford wouldn't do anything about it because you couldn't stick a screw driver through it. I recently bought a MINI that is factory rust proofed. After 6 months it's still leaking rust proofing all over the fenders. Every panel is filled with rust proofing. If it didn't work, when was the last time you saw a rusty MINI?

The rubberized type is garbage. Eventually it will dry out and start flaking off, leaving spaces for moisture and salt to creep into the cracks.....and being conveniently trapped there. I used to do this at a dealership and before I left, some of the first ones I did were being traded back in. All had lots of frame rust.

I spray cheap/used ATF. Seems to work.

fasted58 wrote:

Curmudgeon wrote: That is true. Back in the '90's when I was with GM, adding an aftermarket undercoat or corrosion prevention package voided the factory rust perforation warranty. Still does.

thnx Curmudgeon but would you still have it done regardless? say Ziebart?

Down here we don't need rustproofing since the roads aren't salted. That means unfortunately I have no direct experience with Ziebart etc. I did rustproof my Jensen after replacing the rockers, I used an Eastwood product that was waxy/oily, don't remember what they called it.

Curmudgeon wrote: I used an Eastwood product that was waxy/oily, don't remember what they called it.

Waxoyl is the typical product. Not sure if Eastwood sells that or a house brand names something else.

That's probably what they do. I want to say they call it heavy duty antirust or something like that. Yellowish brown, the drips from the various drain holes lookded like melted candle wax.

Bababooey wrote: .. I think they want your car to rust out after the warranty so you'll buy a new one. ...

Really? "My 8 year old Tacoma's frame just rusted through, I think I'll run back to Toyota and buy another since this one was so incredibly well built!"

The issue with rustproofing is some of the varieties will clog drain holes in the body. Water gets into cavities from the top and normally would drain out the bottom but it's clogged by rustproofing so the car rusts from the inside out. I can see the argument for denying warranty coverage based on that.

Schmidlap wrote:

Bababooey wrote: .. I think they want your car to rust out after the warranty so you'll buy a new one. ...

Really? "My 8 year old Tacoma's frame just rusted through, I think I'll run back to Toyota and buy another since this one was so incredibly well built!" The issue with rustproofing is some of the varieties will clog drain holes in the body. Water gets into cavities from the top and normally would drain out the bottom but it's clogged by rustproofing so the car rusts from the inside out. I can see the argument for denying warranty coverage based on that.

There's always one shiny happy person in a thread that feels the need to attack somebody and leave nothing. And Tacoma's frames are known to rust out. But you knew that right?

In reply to Bababooey:

Pretty sure he wasn't coming after you.

I seriously wouldn't care about GM's rust warranty because like most of them, it is a real joke. Like it has been said, the warranty only covers rust holes, and if it's like here in the great white rusty north, it only covers the body and not the frame. Useless.

I rust-proof my cars with an oil-based product every year. I could show you the underside of my 93 suburban, which as lived its entire life outside here. It was rust-proofed every year and it is in better shape underneath than my father's 04 Subaru which was rust-proofed twice.

I like oil-based products because they can really go everywhere (like the top of the gas tank) and it doesn't block drain holes like the wax based stuff. That last bit is important if it's a DD that lives outside. If it was for a vintage collector car, I would use the wax based stuff because it is longer lasting.

thejoker1 wrote: I purchased a case of Fluid Film to apply on my 2012 GMC Sierra truck. I applied it on the entire undercarriage about 4 weeks ago. Today when I washed my truck, I noticed that the chassis paint was actually washing off leaving bare metal and was very soft everywhere else. This makes me sick to my stomach to think I just spent $40,000 on a new truck and the frame now has bare metal showing in several areas. If I attempt to wash the frame using just a garden hose, the chassis paint will completely come off. The product label states that it will not harm paint or rubber so I'm not sure why this has happened. Also, a friend just told me that if you undercoat a GM truck, it voids the factory corrosion warranty. This Fluid Film is supposed to be a lanolin based oil coating. Would this be considered undercoating that would void my warranty? If so, why wouldn't the Fluid Film company warn you that this might be an issue? Any help or guidance would be appreciated. Thanks

That is bizarre. I would contact Fluid Film directly and send them pictures. I mean, the stuff is just oil, I don't see how it could strip paint. I did my F-150 in August, and was just underneath it last week changing the oil and it looked fine. And I sprayed that stuff everywhere.

+1

I fluid-filmed my '90 F250 this fall and it seems to do the job.

After reading how much the snowplow guys rave about it I figured I'd give it a try.

Shawn

I stopped rust proofing/spraying my cars about 10 years ago. With the exception of Mazda, I haven't seen a late model car or truck with rust on it in years.

In reply to thejoker1:

The chassis doesn't really have paint on it at all. It has a gooey tar like substance. You can rub it off with your fingers when the truck is brand new. I'm not sure this helps you at all, because bare metal is bare metal, but what fell off certainly wasn't paint.

Zomby Woof wrote: I haven't seen a late model car or truck with rust on it in years.

That's because late-model vehicles are all new.. go figure..

^^^^^^ This

When I was looking for a Sentra Spec-V (02 to 05) last spring, 5 of the 6 cars I went to see had a good amount of rust under. Guess which one I bought And when I started shopping for a WRX (again 02 to 05) this fall, 2 of the 3 cars I saw were rusty under. Heck, one of them had its front subframe replaced because of the tin worm. So I'll keep rust-proofing my cars until I see a ten year old car with no rust.

Trans_Maro wrote:

Zomby Woof wrote: I haven't seen a late model car or truck with rust on it in years.

That's because late-model vehicles are all new.. go figure..

Let me clarify. You just don't see rusty 5-10 year old cars anymore ( PQ cars and Mazdas exempt )

That's interesting, I see rusty 5-10 year old cars all the time Frequency depends on how we're classifying "rusty".

I never really believed in the value of aftermarket rustproofing and I never liked the way that they drilled the car full of holes to apply the stuff.

But I will tell you this...

My recently acquired, one owner CRX Si was taken to Zeibart when it was new. They drilled it full of holes, shot the stuff in and plugged them up. He brought the car back for annual reinspection and whatever retreatment they may do (I have the paperwork). And it seems to have worked. It's not perfect, but there is less rust on this CRX than on any other that I have seen in years, and these cars rust like they were made in Italy.

Now, based upon modern production methods and materials, I'm not sure that I'd take my next new car in, but I'd surely think about it.