I maintain our family’s fleet of older vehicles some of which are relatively low mileage considering their model year. 2013 Grand Carvan (71xxx miles), 2011 Terrain (160xxx miles), 2008 Silverado (80xxx miles), 2007 Focus (130xxx miles) and 2005 Grand Carvan (225xxx miles, winter beater).
All but the oldest are in decent shape but each have some bubbles and rusting starting to form in various places. Last fall/winter, I paid about $170 to have Krown applied to the Terrain. After considering the cost, I’ve decided to start undercoating on my own. I’ve watched several youtube videos and researched several forums (including BITOG). The most informative videos were two by South Main Auto where he shows his process.
Here are my random observations after coating two of my vehicles.
Here is what I purchased:
Next, I moved on to my wife’s Terrain. She has a sensitive nose and the Terrain is black so I opted to use Woolwax instead of Fluid Film. It also took about three quarts of Woolwax. I still used about two cans of aerosol Fluid Film with the small flexible extension wand. One advantage of the Fluid Film flexible extension wand is that it is about 0.2 inches diameter so it will fit through smaller holes, like if I remove a door latch bolt to reach in and film the cavity behind it. It was also easier to fit this into some gaps under the hood to spray into the fender cavities.
I do like the Kellsport undercoating gun but the hoses are a bit on the large side (3/8" OD) and only fit a 1/2" hole if going straight in. This makes it tough to angle the hose to reach into a specific area of a cavity. I need to look for some 5/8" plugs as that would give me a little more "wiggle room" to angle the hose. These 3/8" hoses would not fit into some of the existing gaps to fill the fender cavities accessible under the hood.
I also like the aerosol FF spray cans with a small red straw to hit the visible rust on the seams at the bottom of a door or trunk lid. It is very controllable in this fashion.
I am disappointed with the Fluid Film flexible aerosol spray can extension wand. It wants to pull off the barbed nipple too easily and make a mess. Also, it often leaks out under the button and makes the entire can a dripping mess.
I want to make a new tip for the undercoating gun to adapt a very small hose to it. Hopefully I can eliminate the Fluid Film spray can extension wand issues and reduce cost by using bulk product instead of expensive spray cans. This will also help with smell if I can spray bulk Woolwax through small holes on my daughter/wife vehicles.
I hope to do the Silverado next. It is white and I am the primary driver so I plan to use clear Fluid Film exclusively on this one as the smell doesn't bother me. South Main Auto has a youtube short where Eric dumps cinnamon essential oils into the fluid film before spraying. I’m going to try that before spraying the Silverado to see if it will mask the FF smell and get daughter/wife approval.
The Woolwax is definitely thicker but I had no issues spraying it. But I left it sit out in the sun on a hot day before trying to use it.
Before spraying another vehicle, I want to mark each hose about 1 inch from the end. This will help me to know when to stop spraying as I pull out the hose. It makes a big mess if not stopping before the hose ends comes out of the hole!
I do have a lift in my barn. I was pleasantly surprised that the overspray has been less than expected. The Woolwax does make me look younger when the black overspray settles on my gray facial hair.
All but the oldest are in decent shape but each have some bubbles and rusting starting to form in various places. Last fall/winter, I paid about $170 to have Krown applied to the Terrain. After considering the cost, I’ve decided to start undercoating on my own. I’ve watched several youtube videos and researched several forums (including BITOG). The most informative videos were two by South Main Auto where he shows his process.
Here are my random observations after coating two of my vehicles.
Here is what I purchased:
- Woolwax Pro Undercoating Gun by Kellsport, includes two extension wands and three empty bottles - $120 Amazon
- 1 gallon black Woolwax - $70 Amazon
- 5 gallon bucket of Fluid Film - $120 during Amazon Prime Days
- 6 pack of Fluid Film Aerosol Cans with flexible Spray Can Extension Wand - $75 Amazon
- 50 pieces of Rustproofing Undercoat Caps Buttons Plugs for ½” hole - $13 eBay
Next, I moved on to my wife’s Terrain. She has a sensitive nose and the Terrain is black so I opted to use Woolwax instead of Fluid Film. It also took about three quarts of Woolwax. I still used about two cans of aerosol Fluid Film with the small flexible extension wand. One advantage of the Fluid Film flexible extension wand is that it is about 0.2 inches diameter so it will fit through smaller holes, like if I remove a door latch bolt to reach in and film the cavity behind it. It was also easier to fit this into some gaps under the hood to spray into the fender cavities.
I do like the Kellsport undercoating gun but the hoses are a bit on the large side (3/8" OD) and only fit a 1/2" hole if going straight in. This makes it tough to angle the hose to reach into a specific area of a cavity. I need to look for some 5/8" plugs as that would give me a little more "wiggle room" to angle the hose. These 3/8" hoses would not fit into some of the existing gaps to fill the fender cavities accessible under the hood.
I also like the aerosol FF spray cans with a small red straw to hit the visible rust on the seams at the bottom of a door or trunk lid. It is very controllable in this fashion.
I am disappointed with the Fluid Film flexible aerosol spray can extension wand. It wants to pull off the barbed nipple too easily and make a mess. Also, it often leaks out under the button and makes the entire can a dripping mess.
I want to make a new tip for the undercoating gun to adapt a very small hose to it. Hopefully I can eliminate the Fluid Film spray can extension wand issues and reduce cost by using bulk product instead of expensive spray cans. This will also help with smell if I can spray bulk Woolwax through small holes on my daughter/wife vehicles.
I hope to do the Silverado next. It is white and I am the primary driver so I plan to use clear Fluid Film exclusively on this one as the smell doesn't bother me. South Main Auto has a youtube short where Eric dumps cinnamon essential oils into the fluid film before spraying. I’m going to try that before spraying the Silverado to see if it will mask the FF smell and get daughter/wife approval.
The Woolwax is definitely thicker but I had no issues spraying it. But I left it sit out in the sun on a hot day before trying to use it.
Before spraying another vehicle, I want to mark each hose about 1 inch from the end. This will help me to know when to stop spraying as I pull out the hose. It makes a big mess if not stopping before the hose ends comes out of the hole!
I do have a lift in my barn. I was pleasantly surprised that the overspray has been less than expected. The Woolwax does make me look younger when the black overspray settles on my gray facial hair.
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