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Undercoating for Winter

18K views 94 replies 24 participants last post by  HipPopPottedMouse  
#1 ·
I haven't yet been able to check out the undercarriage of my new truck, but I know it came with the skid plates as part of the Ultimate trim. I don't know what parts are covered and what ones are exposed, but I do live in the northeast and winter is coming. I've never had a vehicle undercoated before (I suppose my SUV's fuel lines wouldn't have rusted out and leaked if I had known undercoating was a thing - but then I wouldn't have my new truck, so not necessarily a bad thing 😉), but I definitely want my truck to last.

What do y'all recommend for undercoating this truck, and is it just on the exposed parts or do they do it under the skid plates or coat the skid plates? And what can I expect price-wise?

Thanks!
 
#3 ·
When I first started spinning wrenches in the 80,s, I worked for a dealership in Kansas, they pushed the undercoat and rust proofing when they sold new cars. Friend of mine done them all. At the time, I thought it was a sure nuff ripp off,.. im from Tx and have lived here most my life and very seldom see undercoating in my neck of the woods. But after working on some of the rust buckets that came through that place, it definitely made me a believer. If I lived in cold country, id definitely be having it done.
 
#8 ·
Yeah, let's just say it took them over a week to get the rust off my SUV just so they could fix the fuel leak ... and then four months later the one section they didn’t fix started leaking, so another week to get the rust off. Definitely can't tow anything with it since the hitch is all rusted, and the rest of it under there, plus one of the third-row seats is rusted in and can't be removed. And, four years ago, the brake lines rusted out while I was driving and almost caused me to T-bone a car turning in front of me, finally stopping about a centimeter away from it. Rust is a serious thing for sure.
 
#4 ·
I have always used Ziebart for rust proofing with a yearly inspection. My 2011 LML after 12 years in central IL where they use salt did not have any rust. I also made sure to rinse the underside as much as possible during the winter. Having it undercoated still meant you had to do some work to keep it free of rust. The folded seam at the bottom of the doors I covered with clear POR-15.

I don'r know how many used 2017 and 2018's on a dealers lot I saw one day with rust coming thru from the backside of the rear fender around the wheel well opening. Not a one of them undercoated.

I see film mentioned... why in gawds name would you even fool around doing that yourself?

Ziebart -
Our rust warranty includes unlimited mileage and coverage against road salt, sand, and (normal) road debris. The reason Ziebart can exceed these coverages is because we reapply (as needed) our protection to the vehicle every year.
 
#9 ·
I have always used Ziebart for rust proofing with a yearly inspection. My 2011 LML after 12 years in central IL where they use salt did not have any rust. I also made sure to rinse the underside as much as possible during the winter. Having it undercoated still meant you had to do some work to keep it free of rust. The folded seam at the bottom of the doors I covered with clear POR-15.

I don'r know how many used 2017 and 2018's on a dealers lot I saw one day with rust coming thru from the backside of the rear fender around the wheel well opening. Not a one of them undercoated.

I see film mentioned... why in gawds name would you even fool around doing that yourself?

Ziebart -
Our rust warranty includes unlimited mileage and coverage against road salt, sand, and (normal) road debris. The reason Ziebart can exceed these coverages is because we reapply (as needed) our protection to the vehicle every year.
Googled it and my closest one is over 80 miles away. Sounds like a good product, though! Hard to rinse the car when it will turn to ice because of the freezing temperatures out (don't have a garage for my truck where I'm currently at).
 
#5 · (Edited)
100% get it done and soon, especially if you plan on keeping it for more than 4 or 5 years! Get the oil film/protection barrier down before the salt water hits it. It’s water mixed with corrosive salt and literally gets everywhere and into the tiniest crevices.
Just had a second application of Krown (an annual application) done yesterday before winter hits again. Downside is you get covered in black goop when you work on the vehicle but it‘s better than having everything rusted out and not being able to remove any bolts over time without either breaking them or stripping the head.
 
#10 ·
Yes, I plan on keeping my truck for a long time. I'm getting mud flaps to help keep the salt from splashing up on the paint, too.
 
#7 ·
#14 ·
I'm a fan of Krown first and Rust Check second.I started having vehicles undercoated again after my 06 Colorado had to have rockers replaced after it was approx 6 years old.Traded our 2012 Outlander in 2022 after yearly sprays of Rust Check with no rusted panels.There was some rust on suspension parts .but nothing catastrophic.My 2015 Silverado(Krowned annually) was traded on my 2023 in July with no rust to be seen except for some surface rust on two cab mounts.Whoever you take it to ensure they are pulling tail lights access panels on the tail gate etc to get as much coverage as possible.They will probably have to drill a few holes to get in above the rockers due to reinforcements in the posts.The fellow who does ours(Krown) is very thorough.The 2022 Escape and 2023 Silverado will drip product for two to three weeks after the application.
Ontario is a big fan of the brine solution.It;s gets into everything including infrastructure,bridges etc.All one has to do is look at the brown pine and spruce along the shoulders of the HWYs to see how damaging this salt solution is.
 
#25 ·
#19 ·
Looks like the nearest Krown is two hours away from me. 🙁
 
#21 ·
Anyone use this brand, New Hampshire Oil Undercoating? I Googled undercoating places and a place fairly close to me that specializes in spray-on bed liners and undercoating uses it. They spray the undercarriage and fog other places that are hard to reach, according to their site.


Note they say to not wash the undercarriage because it can wash off the coating and affect the longevity of its protection (normally one year).
 
#55 ·
I had mine undercoated with New Hampshire Oil Undercoating last year. I actually have an appointment next week for an annual inspection and touch up if necessary. I was told not to wash the undercarriage for a couple of days after the initial application but no warnings or instructions after that period. Hard to say after a year how it’s working. It’s messy to work on underneath though.
 
#22 ·
Another nice thing about Krown (other than it works) is your price never goes up for the entire time you own the vehicle. My LBZ is still 99 bux. As mentioned, there are usually discounts to be had on top of that like early spray, CAA, multiple vehicles, free cleaning supplies etc.
 
#23 ·
Anyone use this brand, New Hampshire Oil Undercoating? Note they say to not wash the undercarriage because it can wash off the coating and affect the longevity of its protection (normally one year).
Another nice thing about Krown (other than it works) is your price never goes up for the entire time you own the vehicle. My LBZ is still 99 bux. As mentioned, there are usually discounts to be had on top of that like early spray, CAA, multiple vehicles, free cleaning supplies etc.
Sounds to me like it might be worth the drive for the Krown.
 
#29 ·
Sounds similar to the NH stuff as that also creeps.
 
#27 ·
I had just gotten onto the interstate for a 7 am beautician appt aka barber and kaboom the air bags went off and I saw this deer go up over the windshield and a pillar. The state policeman had to jerk the door open so I could get out. I was darn lucky no one hit me from the reaar end. I went back into town where it was towed to later that day to get my items out of the car and I did not see any deer laying around. The state police officer said he didn't either. I suspect it wondered off and died.

I was lucky to run across that Camaro. Someone was using it for a show car. Spent thousands on the seats and engine bay add ons. The owner his son bought a McMansion home and got into money issues so they sold it to a dealer is how I got my hands on it. Anymore if the airbags deploy the insurance company doesn't want to mess with fixing.

Saturday someone I know showed me a picture of a deer that went thru the front window of a new GMC Sierra Denali and went thru the cab and out the back window and died on the top of the bed cover. OMG. Another person told me her friend died when an antler went thru the windshield and into her head. OMG.

The good thing is my insurance paid me almost near the purchase price of the Camaro so I can't really complain.
 
#28 · (Edited)
We live in NE Idaho and have two 2017 Chevrolet Silverado PU trucks, 2500 gasser and 3500 Duramax DRW.
Had both undercoated when new. Every spring I pressure wash the wheel wells and frame, then place a sprinkler under the trucks for a half hour to rinse the winter grime and salts. No signs of rust in 6 years.
 
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#33 ·
I think that place you listed above will be fine. It’s an oil based type rust spray. The more important thing is the coverage. I got under my truck tonight and checked in the engine bay with a flashlight to have a look at what the guys workers just did on Saturday afternoon and let’s just say I’m not impressed at all… they missed recovering half the vehicle (and now I’m wondering what else they didn’t do!). I’ll be giving the owner a call tomorrow morning..
 
#34 ·
Glad it sounds good!

Oh wow, that's definitely frustrating. They better make it right!!
 
#39 ·
My last vehicle it was $199 for pre-treatment and $599 for the rustproofing on the Bumblebee Transformer Camaro.

What is Pre-treatmet vs Rustproofing?
 
#40 ·
My last vehicle it was $199 for pre-treatment and $599 for the rustproofing on the Bumblebee Transformer Camaro.

What is Pre-treatmet vs Rustproofing?
Ziebart's pre-treatment is used on used vehicles and not a new one. Sorry I should have explained that. Supposedly it treats any rust so the undercoating will adhere to it. It's a 2 day process. Pre-treated one day and undercoated the next day.

I would think with the film/oils mentioned if you used a high powered wash wand at a car wash it would strip it off. Even some of those drive thru wash places I would think the water psi being sprayed would strip it off. With Ziebart you aren't supposed to power wash for 2 weeks I believe. Krown I have heard of and I don't know anything about it. Ziebart I have been using ever since my first new '77 Olds Cutlass. Back then vehicle manufacturers offered almost no protection. Now I think in some areas on a vehicle they use waxes or some coating that probably last just about as long as the 3 or 5 year warranty against rust.
 
#46 ·
I have been doing it myself 3 years running, I use Fluid film or Blaster Surface Shield (basically the same). I live in Eastern WA. I have seen no evidence of rust as of yet on my 2019. I remove the tires, inner wheel well shields and even coat up inside the frame and box. takes about 3 hours. this is after a year, before I re-coat.

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#57 ·
Wow, that's cheaper than here where it is $350 plus there's an option for a $100 additional type of treatment (I'm not sure what the need for it is). Glad it seems to be good for your son's truck!
 
#56 ·
GM coats all HD truck frames with wax undercoating at the factory. It stays soft and if you undercoat over it with anything other than Fluid Film the wax will dry and fall off, taking your undercoating with it.

Fluid Film installer here has a coating for the wax that keeps it pliable. I had them do a level 4 rustproof on my 2024 3500. Special coating on the wax and oil rustproof everywhere else. Cost me $600 but I know it works. Yearly reports are around $100. I had my 2015 Ram done and sold it in August with no rust.

Working on the truck is a bit messy and you can't run thru a high pressure undercarriage wash because r it will remove it.
 
#59 ·
Interesting. I'll have to ask these people if their coating affects said wax or if they have another thing they do for it. Nice that your 2015 was rust-free!