GMC Terrain, Equinox, and SRX Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
37 Posts
Discussion Starter · #1 ·
Hi all,
We have a 2018 Equinox that is still in great shape in terms of rust. This is a vehicle we plan to keep for a while. Is undercoating worth it on newer vehicles? I can get fluid film in my area for $350. I know Chevy uses some rust protection during manufacturing as well, so not sure if this is worth it or a waste of money. We live in the Northeast.
Thanks.
 

·
Registered
2022 Equinox RS, 2021 Camaro LT1 6-Speed, 2002 Camaro SS 6-speed, 2014 Dodge Caravan
Joined
·
36 Posts
Truly depends on how long you plan to keep the vehicle. I usually get mine sprayed once professionally (Krown, Rust Check..etc etc...)

Then every year after that, I buy the cans and do the entire underbody myself. Door jams, rockers etc usually are drilled by the company doing the spraying...I just pop the caps off and spray in there myself year after year...

I have a 2014 Dodge Grand Caravan (I live in Ontario with lots of winter salt) and I have virtually no rust at all under there.

Jason


Jason
 

·
Registered
2011 Equinox 1LT V6 3.0L FWD 173k miles
Joined
·
4,189 Posts
Never done it in my life ... never knew anybody who did it, either ... even up in New England.

My concern with "undercoating" is - what happens when it cracks and road salt gets behind it? Now you're actually holding the salt against the frame ... which is probably worse!

And if you're doing repeated treatments, how do you know that what you're about to spray is completely clean and dry prior to applying the coating? As they say with painting anything ... surface preparation is everything!

The other thing is ... nothing lasts forever ... so how long does it need to last (??) ... 10 years (??) ... 15 years (??) ... I'm betting that if you did absolutely nothing (except winter washes to clear the salt), you'd get at least 15 years usage anyway ... and by that time, you'd have other issues anyway that would factor into the decision of whether to keep the vehicle or not.
 

·
Registered
2022 Equinox RS, 2021 Camaro LT1 6-Speed, 2002 Camaro SS 6-speed, 2014 Dodge Caravan
Joined
·
36 Posts
Never done it in my life ... never knew anybody who did it, either ... even up in New England.

My concern with "undercoating" is - what happens when it cracks and road salt gets behind it? Now you're actually holding the salt against the frame ... which is probably worse!

And if you're doing repeated treatments, how do you know that what you're about to spray is completely clean and dry prior to applying the coating? As they say with painting anything ... surface preparation is everything!

The other thing is ... nothing lasts forever ... so how long does it need to last (??) ... 10 years (??) ... 15 years (??) ... I'm betting that if you did absolutely nothing (except winter washes to clear the salt), you'd get at least 15 years usage anyway ... and by that time, you'd have other issues anyway that would factor into the decision of whether to keep the vehicle or not.
You are thinking the old school rustproofing from the 80's or 90's....No one up here in Canada uses that anymore for ages now. The new stuff is very very liquid based....Like Fluid Film or Rust Check.....Nothing to crack. It does preserve your underbody big time. Check under Rust Check "Coat and Protect" its a very thick almost gel like substance that creeps and remains fluid.

My old 1999 Saturn from the factory had that "yellowish" hard stuff and you are right...once it got penetrated....it would actually make the rust worse as you could not even see it.

Cheers,

Jason
 

·
Registered
Joined
·
253 Posts
It really depends on how long you intend to keep the car. I did the Krown spray on my '09 Vibe thinking I was going to keep it for many years or worst case improve the resale. Turns out my kids wouldn't even attempt to learn how to drive a manual so I caved in, sold it to get a small hatch with an automatic ('18 Sonic). I found the money spent on the annual application of Krown did not translate into improved resale but there was no underbody rust. What I didn't like was the mess it made year round, the swelling of some rubber seals (particularly the hood seals), and the drilling into the door and body panels.
I have not sprayed any of my current vehicles and don't intend to do so as a result. I live in Southern Ontario close to Detroit and don't really see much snow compared to most of Canada so rust hasn't been a huge issue here anyway.

If you do it I would only do the oil based sprays and not the rubber or wax stuff. Those will trap moisture and likely accelerate corrosion.
 

·
Registered
2022 Equinox RS, 2021 Camaro LT1 6-Speed, 2002 Camaro SS 6-speed, 2014 Dodge Caravan
Joined
·
36 Posts
It really depends on how long you intend to keep the car. I did the Krown spray on my '09 Vibe thinking I was going to keep it for many years or worst case improve the resale. Turns out my kids wouldn't even attempt to learn how to drive a manual so I caved in, sold it to get a small hatch with an automatic ('18 Sonic). I found the money spent on the annual application of Krown did not translate into improved resale but there was no underbody rust. What I didn't like was the mess it made year round, the swelling of some rubber seals (particularly the hood seals), and the drilling into the door and body panels.
I have not sprayed any of my current vehicles and don't intend to do so as a result. I live in Southern Ontario close to Detroit and don't really see much snow compared to most of Canada so rust hasn't been a huge issue here anyway.

If you do it I would only do the oil based sprays and not the rubber or wax stuff. Those will trap moisture and likely accelerate corrosion.

Interesting it never swelled any seals on my previous cars that I could tell. Sure it does drip for awhile after its applied. I usually do it in August or September to let is creep in to every nook and crannie so to speak while it still is hot outside so it flows better. I never spray the engine bay, only underbody and rockers for the most part......
Some people only spray it every 2 years....again it totally depends if you are going to keep the vehicle. More then 8 years, I would get it done.....
 
  • Like
Reactions: probak118

·
Registered
Joined
·
253 Posts
Interesting it never swelled any seals on my previous cars that I could tell.
Could be the whole Toyota roots thing with the Vibe...It was so bad the front seal was basically useless and the rear seal at the cowl would constantly slip off the retainers when opening the hood.
 

·
Registered
Joined
·
646 Posts
The lower rear control arms on my 2015 Equinox had to be replaced due to rusting through after 6 years and 62,000 miles or so. GM claims they put a corrosion resistant coating on them, and the GM replacement arms were coated in a gloss black coating, but it must not be very robust.
 

·
Registered
Joined
·
274 Posts
Undercoating is the best thing you can do for a car you are planning on keeping.

$350 seems a little steep though.
 

·
Registered
Joined
·
10,642 Posts
$350 would be a cheap price to pay, providing it really works. But, does it work...the $64,000 question.
 

·
Registered
Joined
·
58 Posts
$350 for Fluid film is steep. I agree. Especially for a coating that washes off during the winter. If they spray into the rocker panels and bottom of each door it makes it more worth the $350. On my wife’s Equinox I also sprayed inside the hood and the rear lift gate. I re-coat every other year. Btw our car is a 2013 Equinox that lives in Michigan winters and has 106k on the clock with no rust. Thanks to Fuid film.
 

·
Registered
2022 Equinox RS, 2021 Camaro LT1 6-Speed, 2002 Camaro SS 6-speed, 2014 Dodge Caravan
Joined
·
36 Posts
Here in Canada we have "Krown Rust Control" and "Rust Check" it costs about 120 dollars to get your car/small SUV sprayed.
The bigger the vehicle the more costly it is. Fluid Film is great but super pricey......

Lately I have been buying "Rust Check Coat and Protect" It is a much thicker liquid, almost like Fluid Film. I like it because it adheres for a much longer time and does not wash off as easily...

 

·
Registered
2010 chevy equinox 2.4
Joined
·
950 Posts
No rust coating, on newer cars with a subframe and painted underneath. The "rust coating" gm uses is paint. Every newer gm vehicle has a painted boxed in subframe with drain holes ECT. I would still take a peak underneath every year but a full underbody coating is unnecessary. If anything I would recommend a DIY once annual can of this
Liquid Fluid Plant Service Ingredient

Or basically any rust inhibitor up the drain holes and on spots like just the welds of the subframe on any tiny rust and control arms ect. I chose this product because I actually use it both on cars and multiple bikes, it sticks for years. The reason is because rust is like cancer it spreads. If you have absolutely no rust there is nothing to worry about but no underbody coating can protect against ....from google... " Iron oxide is formed as the bacteria converts ferrous iron to ferric iron" literally I live in California and I've heard multiple people say their rust is living or cancer. It is a chemical reaction once it starts the car is just infected there's no stopping it so the best way I've found is to inspect my vehicle and any rust at all is completely isolated/ sanded painted removed. A wide cover of underbody coating will not stop the initial rusting proscess at all really... Don't park in the garage the constant temperature change makes moisture inside the subframe that's the real enemy.
 

·
Registered
Joined
·
37 Posts
Discussion Starter · #15 ·
"don't park in the garage".. LOL... Tell that to my wife in the middle of a Michigan winter
So overall it sounds like it's probably not worth doing, unless I can do it for significantly cheaper than $350. Does Chevy actually use rust protection on their vehicles?
 

·
Registered
2010 chevy equinox 2.4
Joined
·
950 Posts
From the gm website.

Chevrolet vehicles are designed and built to resist corrosion. All body and sheet metal components are warranted against rust-through corrosion for 6-years/100,000-miles (whichever comes first). Application of additional rust-inhibiting materials is not required under the corrosion coverage and none is recommended.

Independent dealerships might but no, they don't come with any extra coatings all the cars are the same.
 

·
Registered
Joined
·
274 Posts
So overall it sounds like it's probably not worth doing, unless I can do it for significantly cheaper than $350. Does Chevy actually use rust protection on their vehicles?
We're seen some interesting answers for sure.

My recommendation is still to have it done with a soft undercoating IF you live in an area where salt is used.

Where I live in atlantic Canada, we used a lot of road salt. We also do regular safety inspections. I'm the service writer for a 6 bay shop. A lot of underbodies have rust starting after 5 years and have holes after 7-8 years.

GM's factory rustproofing is worlds better than it used to be. But again, depending where you live, you still need to rustproof something you plan to keep.
 
1 - 17 of 17 Posts
Top