Underbody flush/salt remover

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Any suggestions on a good underbody flush routine? Just purchased the wife a new-to-us truck and it snowed the next two days! Talked her out of taking it the first day, but now the salt is down and shes out driving it without any rust-proofing. I will need to flush out the underbody before rustproofing, so looking at some options. Even if I get a nice enough weather break where I can do this without the water freezing not sure how well a rinse down will work, as I usually wait until after a number of summer rain storms for a late-summer application on my vehicles...
 
Just find a high quality touchless carwash with a high pressure underbody spray. Go through more than once if it inst thorough enough. You'll need high pressure water to really flush off the salt. I would highly suggest against any sort of rubberized undercoating, in case that's what you're thinking.
 
No, I'm looking at options such as Fluid Film and Cosmoline 342. Actually really looking at the Cosmoline 342. Even comes in aerosol or bulk for spraying...
 
I tried out fluid film this year for the first time. I sampled it in the aerosol can on just a few spots i thought would be prone to rust. Overall it was more runny than i thought and I'm concerned about it's longevity. Granted that could be 100% down to my application technique or some usage error i made. I read rave reviews for it all over the interwebs.
 
Touchless car wash through the winter, get an unlimited monthly plan and use it ! Apply rust protection in the summer, douse it good and find a nice long dusty road ! I like Fluid Film myself.
 
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Originally Posted by JoelB
I tried out fluid film this year for the first time. I sampled it in the aerosol can on just a few spots i thought would be prone to rust. Overall it was more runny than i thought and I'm concerned about it's longevity. Granted that could be 100% down to my application technique or some usage error i made. I read rave reviews for it all over the interwebs.



You can get Fluid film at Napa for under $40 for 1 gallon. I picked up three cans last month for $32 each they had a promo for 20% off. You can buy the gun and wands and if you have an air compressor you can get it fully protected in 1/2 a day on your driveway or garage. What I like about Fluid film is that it doesn't drip everywhere. It will wash off the underside of the vehicle eventually, but it sticks inside the door panels and hinges etc.

http://www.kellsportproducts.com/undercoatingguns.html


https://www.napaonline.com/en/p/FFQCNAS
 
The places that spray products typically use compressed air to clean the vehicle before spraying. As long as you to not have a thick layer of mud covering rust or salt, cleaning with compressed air and spraying the product will deal with any metal that has salt on it. It will penetrate the salt and rust.

However I do typically go through a car wash with undercarriage wash on my way to getting the vehicle sprayed.
 
I think FF and Krown are pretty competitive products.

More important than brand choice is quality of application. Poor application will render both products useless just as a quality application will produce great results from either.


I chose FF. While it seems easy to wash off, it does provide great protection. It gets better with each application because as dust and dirt accumulate, and as more and more FF is applied, it builds up into quite a durable coating. Almost grease-like.

After about 4 years of applications, I stopped applying on my Crown Vic because it's really stuck to the car now.


As far as an underflush, I just kick the lawn sprinkler under my vehicles on warm-ish days throughout the winter.
 
I am sorry for a small deviation. Those who recommended touchless wash, have you actually checked if it indeed washes from the bottom? I have 2 near me and they advertise they do but none of them actually do. I confronted them once and the lady told me that it dried out by the time you reached home. This, in the middle of dead winter. The guy standing next to her asked me if I really went underneath. I asked him, he should go and check. So what I am getting at, our locals are just crooks. They know we can not wash our cars due to an ordinance.

I just use $5 garden sprayer to wash off the salt. I usually spray during the lunch and keep the car under the sun, so hopefully, some of the water dries out b the time I head home.
 
got a nice low mile nissan frontier from CarMax, it was a very cold day + i mistakenly didn't ask to have it moved inside for a better look. after purchase it was taken inside for a quick wash + when i got it home for close inspection i seen the bad effects of salty massachusetts when i later checked into it!! prolly never washed the underside!!! other flaws as well + paying TOO MUCH for it was MY fault, NEVER again CarMax!!!
 
Originally Posted by MoneyJohn
I am sorry for a small deviation. Those who recommended touchless wash, have you actually checked if it indeed washes from the bottom? I have 2 near me and they advertise they do but none of them actually do. I confronted them once and the lady told me that it dried out by the time you reached home. This, in the middle of dead winter. The guy standing next to her asked me if I really went underneath. I asked him, he should go and check. So what I am getting at, our locals are just crooks. They know we can not wash our cars due to an ordinance.


The place i like to go has 6-8 nozzles in the concrete floor that spry up. I can see it on the car in front of me and hear it as i drive over it in my car. But not all of these car wash places are created equal surely.
 
Fluid Film does really work, especially, after a few applications. My ~11-year-old car, which is used in a heavily road-salted NY, remains rust-free.
 
Originally Posted by DIANgEMinONV
Fluid Film does really work, especially, after a few applications. My ~11-year-old car, which is used in a heavily road-salted NY, remains rust-free.


And, my 16-year-old vehicle is rust-free / also using Fluid Film.
 
My oldest vehicle is a 21 year old 4Runner. It has been used on heavily salted roads every winter. I've always just used a garden hose with a nozzle to spray the salt off the body and undercarriage as needed. Yes, it can be a hassle in below freezing temps, and you have to drain the hose completely after each use, or it will freeze solid. These days it pretty much only gets used for winter driving, or four wheeling trips. The upside of being proactive in keeping the salt washed off, is that it's rust free.
 
Get a section of pvc pipe and drill holes in it. Sandwich that between two boards. Glue a compatible hose fitting on one end and a cap on the other.

Hook it up to a hose and drive over it slowly. In the summer kids can use it to cool off.
 
It's so nice being south of the Mason/Dixon line.

Salt is not anyone's friend, and fortunately almost never used here.

The underbody of the SUV here just got completely cleaned via a carwash. Wheel wells are also like new.
 
Originally Posted by StevieC
https://shopusa.krown.com/products/salt-eliminator-mr35 (Buy Here)

0:51 into the video they show the exterior of the vehicle. Can be used underneath as well and and won't wash off any under oil spray you might have, just the salt.



Interesting. I didn't know Crown sold to the public like that... I wonder how well their aerosol works? For example, I have found Fluid Film aerosol to be much lighter and more "runny" than the non-aerosol bulk/
 
I've used the salt eliminator on my carpet mats because they were black in my current Dodge and my past Dodge and it works really well for that. I bring in a ton of salt with my shoes by getting in/out of the car frequently in the day during my sales calls.

I imagine it would work just as well on the metal areas as they show in the video, because the way it works is it binds to the salt and allows you to wipe/rinse it away and it does so without a degreasing action so if you have a oil under-spray it will leave that alone.

That said I've never used it on my vehicles as I didn't see the need, but then again I have them sprayed with oil so that might be why I get away with it.

The oil undercoating spray they actually sell on their site as well if you wanted to spray it and up through the bottoms of the doors before the winter, You can other areas by removing existing rubber plugs or door switches etc.
wink.gif
 
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