Fluid Film as Undercoating Question

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Using FF as undercoating just about everywhere on my Silverado. I know SOP is to put on in warm weather, blast off and wash after winter, and apply again. However, I'm crawling under the truck and coating places that I guarantee I will never be able to get to with a pressure washer or car wash. At the same time, the FF will undoutedly collect grime and salt here. Question--Does anyone know for sure, can an old coat of FF with grime (and SALT) just be covered with a new coat of FF and still protect?? FF's website talks of sealing and self-healing, so surely this would work? If so, I likely won't mess with washing any of it before reapplying.
 
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My situation: I always had my vehicle 'oil' treated in the Fall. Never washed it off after Winter / Yes it's very dirty & greasy underneath. A lot of the oil stayed on after Winters / I never worried about the oil absorbing any salt, but always thought about it. Now I don't drive as much in Winter weather so every Spring it still oily. On the rare occasion I go to an Indy Mechanic, I will first go to the self-serve car wash and clean up the area for them.
 
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Why would you blast it off after the winter? I would just recommend a touch-up of high-spray areas before winter. That's always been my strategy. The FF will last a long time on areas that don't get a constant spray of water. I don't think FF or any oil "absorbing" salt and causing rust is an issue. We've all seen oil prevent rust on vehicles, whether it was from oil leaks or whatever. If it absorbed salt and made rust worse, we'd know it.
 
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I would not worry about trying to remove the remaining Fluid Film before reapplying. I have been using it for a couple of years and it works better than I expected it would as an undercoating. It creeps well and seems to do a great job displacing moisture and penetrating existing corrosion. Once it gets dirty it does not seem to wash off easily either. As long as it is still coating everything, I don't think that any dirt or salt that is stuck to it will bother anything. Rust needs moisture and oxygen to spread. Andrew S.
 
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I just wash off the big chunks of dirt, mud, etc and re coat every fall. The underside of my 01 Wrangler looks amazing even after Iowa and Wisconsin winter after winter.
 
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Oil (lanolin) and water don't mix. So the water will bead on top of the oil and the salt will dissolve in the water, not the oil. FF slowly drips off over the summer so by next fall you're down to bare metal again. I hose FF on in fall before the first road salt, and don't really care if I get it on road grime/ sand. Makes a mud that protects. Someone needs to lick a representative glob of FF midwinter to see if it tastes salty. wink
 
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Been using the bulk FF on my F150 for a couple winters now and I will say it both washes off as well as stays in place... If that makes any sense. The more of a grimey caked up layer of grunge that is present the more durable it is. A bulk coating will result in some rinsing off with a good hose down but its not possible to quickly rinse it off. Over the course of a winter it will rinse off in high wash areas regardless of the amount of grunge you try to build up. What seems to be working for me (I say seems because its only a few years old) is to spray on some time during mid to late summer. This balances (hopefully) a lot of driving in rain and such after the road salt is long gone to rinse out the under carriage (along with some intentional hosing off, especially of obvious areas of build up and entrapment). Later in the summer while there is still hot weather left (to help with both application and subsequent creep_ I like to respray on a nice hot and dry day. In a perfect world I then go cruise some dry dusty dirt roads. Some areas seem to rinse clean over the winter but the majority of the underbody has built up a bit of a grimy coating. Doesn't SEEM to be developing any new rust in most areas (one trouble spot on the cab in a high wash area that I'm not sure how to address short of pulling the doors for a repaint).
 

AMC

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Originally Posted By: lukejo
Using FF as undercoating just about everywhere on my Silverado. I know SOP is to put on in warm weather, blast off and wash after winter, and apply again. However, I'm crawling under the truck and coating places that I guarantee I will never be able to get to with a pressure washer or car wash. At the same time, the FF will undoutedly collect grime and salt here. Question--Does anyone know for sure, can an old coat of FF with grime (and SALT) just be covered with a new coat of FF and still protect?? FF's website talks of sealing and self-healing, so surely this would work? If so, I likely won't mess with washing any of it before reapplying.
The little bit of grime and salt that the fluid film will hold is no big deal. I too give it a good pressure wash in the spring and start over in the fall, that strategy works great. Now, I must warm you. I don't know what year your truck is but Fluid film will majorly soften the black coating GM uses on their frames. I use fluid film on my Silverado too but I do not get it on the black frame. Again, DO NOT PUT IT ON THE BLACK FRAME! Everywhere else is fine but avoid the black waxy coating, if your truck still has it. If your black frame coating is curling or peeling than a very light coat of fluid film may actually soften it and make it repair itself but otherwise, I wouldn't get it on the black frame.
 
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My 2015 Focus has had FF applied twice now and I'm surprised how much is STILL coated. The old wives tale is that it rinses off easily. I haven't experienced that much at all.
 

lukejo

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Originally Posted By: AMC
Originally Posted By: lukejo
Using FF as undercoating just about everywhere on my Silverado. I know SOP is to put on in warm weather, blast off and wash after winter, and apply again. However, I'm crawling under the truck and coating places that I guarantee I will never be able to get to with a pressure washer or car wash. At the same time, the FF will undoutedly collect grime and salt here. Question--Does anyone know for sure, can an old coat of FF with grime (and SALT) just be covered with a new coat of FF and still protect?? FF's website talks of sealing and self-healing, so surely this would work? If so, I likely won't mess with washing any of it before reapplying.
The little bit of grime and salt that the fluid film will hold is no big deal. I too give it a good pressure wash in the spring and start over in the fall, that strategy works great. Now, I must warm you. I don't know what year your truck is but Fluid film will majorly soften the black coating GM uses on their frames. I use fluid film on my Silverado too but I do not get it on the black frame. Again, DO NOT PUT IT ON THE BLACK FRAME! Everywhere else is fine but avoid the black waxy coating, if your truck still has it. If your black frame coating is curling or peeling than a very light coat of fluid film may actually soften it and make it repair itself but otherwise, I wouldn't get it on the black frame.
Yeah, I had read that elsewhere, but that black coating is already wearing thin or flaking in spots. Plus, if I plan to keep FF on constantly, I guess it doesn't matter if the black is dissolved of it now or flakes off next year. (That's my thinking anyway.) Also, where the black is flaking up, there is already rust under the flakes...no better than regular coats of FF.
 
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Originally Posted By: AMC
Originally Posted By: lukejo
Using FF as undercoating just about everywhere on my Silverado. I know SOP is to put on in warm weather, blast off and wash after winter, and apply again. However, I'm crawling under the truck and coating places that I guarantee I will never be able to get to with a pressure washer or car wash. At the same time, the FF will undoutedly collect grime and salt here. Question--Does anyone know for sure, can an old coat of FF with grime (and SALT) just be covered with a new coat of FF and still protect?? FF's website talks of sealing and self-healing, so surely this would work? If so, I likely won't mess with washing any of it before reapplying.
The little bit of grime and salt that the fluid film will hold is no big deal. I too give it a good pressure wash in the spring and start over in the fall, that strategy works great. Now, I must warm you. I don't know what year your truck is but Fluid film will majorly soften the black coating GM uses on their frames. I use fluid film on my Silverado too but I do not get it on the black frame. Again, DO NOT PUT IT ON THE BLACK FRAME! Everywhere else is fine but avoid the black waxy coating, if your truck still has it. If your black frame coating is curling or peeling than a very light coat of fluid film may actually soften it and make it repair itself but otherwise, I wouldn't get it on the black frame.
Yes, and Amsoil HDMP is a great alternative for the black frame
 

JHZR2

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Originally Posted By: leje0306
Originally Posted By: AMC
Originally Posted By: lukejo
Using FF as undercoating just about everywhere on my Silverado. I know SOP is to put on in warm weather, blast off and wash after winter, and apply again. However, I'm crawling under the truck and coating places that I guarantee I will never be able to get to with a pressure washer or car wash. At the same time, the FF will undoutedly collect grime and salt here. Question--Does anyone know for sure, can an old coat of FF with grime (and SALT) just be covered with a new coat of FF and still protect?? FF's website talks of sealing and self-healing, so surely this would work? If so, I likely won't mess with washing any of it before reapplying.
The little bit of grime and salt that the fluid film will hold is no big deal. I too give it a good pressure wash in the spring and start over in the fall, that strategy works great. Now, I must warm you. I don't know what year your truck is but Fluid film will majorly soften the black coating GM uses on their frames. I use fluid film on my Silverado too but I do not get it on the black frame. Again, DO NOT PUT IT ON THE BLACK FRAME! Everywhere else is fine but avoid the black waxy coating, if your truck still has it. If your black frame coating is curling or peeling than a very light coat of fluid film may actually soften it and make it repair itself but otherwise, I wouldn't get it on the black frame.
Yes, and Amsoil HDMP is a great alternative for the black frame
Perhaps. I didn't have success using Hampton on scored/exposed areas on a car I used it on. I only like waxes on areas not subject to damage. Were you able to confirm that hdmp actually "merged" with the existing OEM coating to be seamless?
 
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I like areas to be clean before applying a coat, or re-coating with a rust preventive product. Clean is the operative work, not sterile. In other words I give it a quick once over and get off what I can, allow a few days for it to dry and apply the coating. That method has served me well with vehicles I've treated. I'd rather not spray a coating over road salt residue, or caked on mud if I can clean it off. Hard to access areas, I do the best I can with, but won't lose sleep if they're a little dirty.
 

AMC

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Originally Posted By: leje0306
Yes, and Amsoil HDMP is a great alternative for the black frame
No, it isn't. I tried Amsoil HDMP and Corrosion-X HD before I tried fluid film on my truck and all of them still softened the coating to the point of making the coating come off very easily. Even just accidentally rubbing my pant leg on the frame treated with HDMP while crawling under the truck made a smear and thin spot in the coating. If you have a GM truck and want to preserve the frame coating, I recommend you purchase a relatively light duty / low powered pressure washer and rinse the undercarriage once a week or so during the winter. Once the coating has come off in large areas, game on. Coat the frame down with whatever heavy duty rust preventative you like and don't ever stop re-applying it while you still want to care for it. IMO, GM really dropped the ball with that black waxy frame coating they use.
 

JHZR2

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Originally Posted By: AMC
. IMO, GM really dropped the ball with that black waxy frame coating they use.
Are they replacing frames the way Toyota has to?
 

AMC

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Originally Posted By: JHZR2
Originally Posted By: AMC
. IMO, GM really dropped the ball with that black waxy frame coating they use.
Are they replacing frames the way Toyota has to?
No, the steel they use doesn't rust as bad and us American truck owners are used to dealing with rust anyways laugh The only place my frame is badly rusted is where I lift the truck with the jack. The black coating scrapped off during the first oil change and has been rusting away since. fluid film has slowed it down but I don't think anything can completely stop rust, not where I live anyway.....
 
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Originally Posted By: AMC
Originally Posted By: leje0306
Yes, and Amsoil HDMP is a great alternative for the black frame
No, it isn't. I tried Amsoil HDMP and Corrosion-X HD before I tried fluid film on my truck and all of them still softened the coating to the point of making the coating come off very easily. Even just accidentally rubbing my pant leg on the frame treated with HDMP while crawling under the truck made a smear and thin spot in the coating. If you have a GM truck and want to preserve the frame coating, I recommend you purchase a relatively light duty / low powered pressure washer and rinse the undercarriage once a week or so during the winter. Once the coating has come off in large areas, game on. Coat the frame down with whatever heavy duty rust preventative you like and don't ever stop re-applying it while you still want to care for it. IMO, GM really dropped the ball with that black waxy frame coating they use.
Yes, it is. It’s worked great on my GMC. It’s the HDMP is waxy, just like the factory coating. So it your point is that it’s soft, then of course, it is soft.
 
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Originally Posted By: stephen9666
Why would you blast it off after the winter? I would just recommend a touch-up of high-spray areas before winter. That's always been my strategy. The FF will last a long time on areas that don't get a constant spray of water. I don't think FF or any oil "absorbing" salt and causing rust is an issue. We've all seen oil prevent rust on vehicles, whether it was from oil leaks or whatever. If it absorbed salt and made rust worse, we'd know it.
Is this the general consensus about Fluid Film and similar products? This is the way I've always done it, but was not sure if it was the best strategy. Basically spray Fluid Film and re-apply Fluid Film after the season without pressure washing off the old coat. What about products like "Salt-Away"? Anybody use that? I never understood why just pressurized water would not be enough to rinse off salt and one would use a chemical like Salt-Away?
 
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