Rinse undercarraige in winter or no?

This is why most of my previous cars were purchased from the south. My parents used to live in Georgia, so I would have my dad scout out cars, then I would fly down to get them. Anything from MN people usually give up on rust proofing after 3-4 years and just let it go.

 

Bought the gun for fluid film/woolwax and spray every fall….rinse /clean in the spring….my research indicated good luck with this method long term but I am only 3 years in so can’t say for sure about my situation…. I have let new cars that were daily drivers go and they get rusted to $#i t in about 8 years in New England/ North east…. Also my Dad worked as a mechanic for a local highway dept here and they sprayed all therir trucks with fluid film and they lasted decades from what he said….

 

I am in South Dakota and most of the drive thru car washes here have an undercarriage wash with several water jets spraying straight up as you drive in the car wash. I don't undercoat and go thru a car wash almost weekly in winter to get all the salt, etc.. off top and bottom. I rarely use drive thru car wash when it warms up. Every spring I Simple Green and pressure wash underside and then hit a few spots that has light surface rust with black paint. Just an observation, but the vehicles that never appear to get washed are also the ones with rust in fenders and lower rocker panels.

 

I love the smell of Fluid Film in the morning. It smells like.....rust prevention.

I applied FF on my '76 40. Made sense on that truck. A new Taco?

C'mon. Just get a car wash. There are better things to be worrying about.

 

I bet all the people with 2nd gens thought the same thing until their frames rusted in half. And they didnt make much of a improvement on the 3rd gens.

Its simple preventative stuff that can save you money in the long run.

 

it wouldint be a proper forum if all responders actually contributed actual answers to the question.

 

. Same here. You can catch it on sale at Menards for $3 a can. Leaves a film that last long time.

 

I do not wash my undercarriage/frame during the winter. But I do make it a point to deliberately take it out for a 15-20 min ride whenever we get a good rain storm here during the winter. I try to hit a few good puddles and sometimes take it on the interstate to the next exit and back and the tires kick up that dense spray. Here in southern New England the storms are about a 50/50 mix of all rain or snow during the winter and it does a good job of washing away off most of the salt coating under there; especially if it has been raining for a while and most of the surface salt on the road has been washed away already The worst time to go out is if they have done that pre-treatment before the snow or ice arrives. I hear that brew is basically pure liquid salt and worse than driving your vehicle through the surf along some beach.

If I only had one choice to pick for protecting, I think I would pick the inner surface of the rear bumper. They replaced the one on my son's 2005 when they did the frame and it was already showing surface rust on the inside when be bought it. First winter with the new frame was still three months away. I swear those chrome bumpers are rusty already straight out of the sealed box. Mine still looks ok, but it does have some spots showing. Before next winter comes, I swear I will empty an entire can of fluid film on the back side of it!

 

Another New Englander here.... With something like Fluid Film, Woolwax, etc I stay away from washing the underside in winter, especially pressure washers.
I'm not a fan of pressure washers on cars in general. They force water where it shouldn't be, can rip rubber/seals if used improperly, and can blow off waxes/sealants when they hit paint. That being said, I do use the touchless pressure washer car wash in winter.
I have cars that are not treated, and those get their undercarriages rinsed with Salt-Away. Years ago I found something that's basically a long, narrow PVC with tiny holes for washing under the car that hooks to the regular hose, not the pressure washer. Combined with the Salt-Away it's been working great for years.

Edit: found the contraption
https://www.theunderwasher.com/

Salt Away SA32M Concentrate Kit with Mixing Unit, Salt Removing Cleanser, 32 Fl. Oz.

$48 Salt-Away® Concentrate Kit with Mixing Unit 32 fl oz - 946 ml)

https://www.amazon.com/dp/B0000AXNJO

 

Coming from someone who doesn’t live in Colorado. There is no need for undercoatings here... just spray it off periodically and move on. There is a reason no cars born and raised in CO are rusted out. We live in a desert.

 

Just boss waxed my 2022. Car wash weekly while Im in MI.
1st time dealing with this salt crap. Sucks.

 

Whats the point of putting FF or WW on if you're just gonna brush it off? Makes no sense.

Go on youtube and look up repairgeek (I'm assuming that's who you're talking about). He has tested all these products over 4 or 5 years and has found washing it doesn't do anything but weaken the undercoat. Fluid Film it once or twice a year and wash thoroughly in the spring and fall (before you reapply).

 

People don't realize this either. I frequent Florida and I see trucks with rusty frames and rusted through bodies just driving through traffic all the time.. humidity and salty ocean air causes rust too.

I live on the atlantic coast and get a mixed bag of mild-snowier winters (our winters are nothing like the North East and North West) and I Fluid Film my truck twice a year. I won't wash my frame, only the body. I will at most lightly mist the under carriage.

 

It doesn't come completely off despite the nonsense you hear on here. The next summer water still beads right off the entire frame. In addition the areas that are hit with the wash are cleaned of salt... the areas that aren't are protected by the WW. I also don't like the paint of the car sitting covered in salt.

 

You can wash the body of the truck without doing the frame lol

 

I go to an auto carwash local to me. Undercarriage spray is included. I'm not washing my car by hand in the winter.

 

there is no way the undercarriage spray for 20 seconds will get in all the nooks and crannies to wash out the FF. Nothing to worry about. you would need to use a degreaser, then powerwash by hand every inch to get FF off.

 

Glad you like the smell. I can't stand any of them. They remind me of someones dirty, moldy socks sitting around.

 

Ah,....you guys are doing it all wrong.

You need to coat the bottom of the truck with a thick layer of ice. Just hop over to the local pay-n-spray in sub zero temps. Spray the underside of the truck, back out of the bay for about 5 minutes allowing time to freeze. Apply about 3-4 layers.

Now, any salt or brine or sand will just impinge on the layer of ice and not make contact with the truck.

Side advantage is the added weight will help with traction.

 

I'm not worried in the slightest.