New Vehicle Undercoating - Cosmoline, Woolwax, Fluid Film, etc???

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I may be purchasing a new GM truck in the near future and living in the Northeast I'd like to get ahead of rust prevention as much as possible. I've read good reviews about Woolwax, Krown, Cosmoline and Fluid Film and wondering which works best in the rust belt. I typically am a DIY'r and would prefer not to go to a dealer to get it done.

Costs aside, is one better than the other? I'd like it to be able to wick into the nooks and crannies as much as possible and be fairly permanent. Bonus points if it doesn't come off on contact so if I'm working on the truck I don't look like I've been tarred and feathered!

Thoughts?
 
I like Fluid Film. It creeps into the nooks and crannies and "sticks" in place without dripping.
It's also a natural substance, so if I end up inhaling it thru the HVAC system of my car, or some animal/critter eats it, no harm.

Only downside is it needs to be re-applied once every year for daily driven vehicles.
 
You listed four good choices. I use fluid film myself, stick it on every October or November just before the first frost. It is a little thin so I wait for those cooler days so it's thicker.

Some of it does wash away but if it means my car lasts 20 years instead of 15 I'm happy.
 
I have no problem re-applying once (or even twice) per year, I tend to over-kill things anyways. Is fluid film sticky? After it dries does it tend to come off all over you if you have to work underneath your car?

A "waxy" substance like Cosmoline sticks out as a good alternative to the sticky/oily tar stuff. I've not used any so I'm going off of third hand knowledge (which is why I'm here asking!).
 
The best one is the one used by the best place around you.

You want thin so its self healing.. and doesnt block drip holes.
everything needs applied yearly.

Krown in Canfield is great so Krown it is.
I'd prefer something a little thicker in the wheelwells etc..
Woolwax vs fluidfilm

IIRC: woolwax is used in high spray areas and FF in nooks and crannies.(frame doors etc) Same company makes both.

Its a dirty nasty job to spray it without a lift so I'll save my lungs and pay the 150$ yearly.

For the amount they used I'd need 6-8 cans.. and their high pressure wand works better than the aerosol can.

The subi dripped for 5 days.. they sprayed it down well and everywhere its needed..
 
Toyota uses noxudol 300 in their frame recalls. Noxudol 300 won’t wash off, but stays relatively soft. Similar to a wax coating but not quite. Lots of active chemicals to combat and inhibit corrosion. Won’t damage any rubber bushings or hoses.

Noxudol 700 is an internal cavity wax that creeps heavily until it cures (at least a week). It is then a soft wax.



This is what the 300 looks like right after application. It takes up to a week to cure.

You do a full application initially and touch up if/as needed annually. Only in the very high spray areas need touch up
 

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@mattd That stuff looks pretty good! After the 300 has cured for a couple weeks if I were to run my hand along it would I be wearing it all over myself? Or does it more or less "scrape" off...but not really "rub" off? Thanks!
 
If you graze it it will leave a little residue but if you really drag your finger on it it will come off. But it does not flake. More of a smear. Like a softish sticky wax

I notice in the wheel wells it is much less tackey.
 
I have no problem re-applying once (or even twice) per year, I tend to over-kill things anyways. Is fluid film sticky? After it dries does it tend to come off all over you if you have to work underneath your car?

A "waxy" substance like Cosmoline sticks out as a good alternative to the sticky/oily tar stuff. I've not used any so I'm going off of third hand knowledge (which is why I'm here asking!).
It doesn't really "dry" and yes it comes off on you when you work under the car. I paid up and used Cortec VPCI-368, it creeps and over time dries, it doesn't come off as easily as FF and it lasts longer. Noxudol is another good product. Both products cost a lot more, but imo are worth it.
 
Many newer cars have plastic panels on the underside to improve aerodynamics. Are these panels removed when applying the undercoating?
 
Many newer cars have plastic panels on the underside to improve aerodynamics. Are these panels removed when applying the undercoating?

They should be. I know I went above and beyond what very few would do for my truck (removed both bumpers, fuel tank, all wheel well liners and spare tire assembly).
 
Many newer cars have plastic panels on the underside to improve aerodynamics. Are these panels removed when applying the undercoating?
They'd better be! I'll be doing it myself...so yes they will be removed. As will any wheel well liner too.
 
Don’t expect to have a dry to the touch coating. That’s already there i.e. paint. The ones that actually work long term are all “wet” and will attract dirt over time and get you dirty when touched. There is no way around it.

If you want a clean truck underneath to work on, then prepare a strict regimen of washing the underside at least once a week during winter.
 
I may be purchasing a new GM truck in the near future and living in the Northeast I'd like to get ahead of rust prevention as much as possible. I've read good reviews about Woolwax, Krown, Cosmoline and Fluid Film and wondering which works best in the rust belt. I typically am a DIY'r and would prefer not to go to a dealer to get it done.

Costs aside, is one better than the other? I'd like it to be able to wick into the nooks and crannies as much as possible and be fairly permanent. Bonus points if it doesn't come off on contact so if I'm working on the truck I don't look like I've been tarred and feathered!

Thoughts?
For a brand new vehicle, I would drive it off the lot directly to a Ziebart for real under coating that will last. Do it before any crud has a chance to adhere to the undercarriage.
 
Ziebart is the only shop near to me. I've not heard good things about them but those are just local opinions which is why I was considering the DIY route. Either way, some protection will be applied ASAP when I get the vehicle.

I'm not too excited to remove the brand new door panels to get inside the door cavity but it is what it is!
 
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