Pressure washing undercarriage without drying cause rust?

Hello,
I pressure wash undercarriage off my Tacoma when I wash the truck every month or so to remove any road dirt and let it air dry.
I am wondering if pressure washing once a month and not drying it right away and let it air dry will cause rust.

 

No worse than driving in the rain.

 

Unless you are rapidly drying your car after driving in the rain, its going to be the same deal.

 

These questions....lol

 

And it's only Wednesday.

 

It's road salt or salt water that causes rust. As long as you completely rinse the undercarriage off and don't leave any rust causing debris it shouldn't rust. I use a foam cannon to wash my truck and foam and clean the undercarriage every wash especially after driving in the rain. No rust, but I'm also in the desert. You can spray the undercarriage with detail spray or a rust inhibitor for extra protection if you're worried about it. I'm not sure what the most popular coating is in northern climates. I use Adam's, but it's more for show and not rust prevention.

https://adamspolishes.com/products/adam-s-invisible-undercarriage-spray

https://www.tacomaworld.com/threads/rust-prevention-treatment-consolidation-thread.355928/

 

I try to avoid any pressure washing on my trucks. If you do an adequate rust proofing job you shouldn't have to.
After a good application of cosmoline almost 3 winters ago, i inspected my undercarriage nearly 3 years later with the salty wet roads here. Found everything the same as almost 3 years ago. That rp-342 cosmoline is the best stuff I've ever used. Fluid film sucks in comparison.

 

Pressure washing is not a good idea, IMO. It can shove water where it shouldn't be, remove protective film, tear apart rubber, etc. I realize lots of people do it without having any issues, but that doesn't mean it's ideal.
Better off with a normal garden hose pressure. Check out Salt-Away. It dissolves salt and leaves a film to prevent rust so drying won't be a concern. It won't replace a real rust prevention like Wool Wax, Cosmoline, etc. but it's better than nothing.

 

Maybe If you use 0-25° nozzles from a foot..

 

Actual proven tests (at least in the military labs) is to not pressure wash. The only way to truly clear salt is volume of water. Someone above mentioned getting water in areas in places it shouldn't go due to pressure washing and this is absolutely correct. Just hit it with lots of water to clean and then using a wetfilm (as mentioned) is the best way. This is such a huge military issue. We spend ~20B annually on material/labor for prevention and correction for all weapon systems and facilities. Crazy right?!?!

 

I take a pump sprayer to the local pay and spray every couple of months, to give it a quick sudsing. I see very minimal surface rust on the welds. Its a good idea in my opinion to wash it down on occasion. Don't be a slave to it. If you really wheel like some of these cats here, then you gotta do your best to wash that crud off of the undercarriage .

 

If you're not using the real pressure from the pressure washer, then why bother? You're just spraying a lower volume of water in a mist.
Pressure washers were designed for removing stuff from permanent surfaces. Not a great idea for vehicles. It kills me to see people pressure washing their paint. Insanity.

 

right....maybe to get mud and stuff off, but not for cleaning in general! I try to use low pressure just to reach the center area that isn't easily reachable....I figure better than nothing.

 

And people still complain about a measly 10B on the JWST!

 

do you dry the undercarriage after you drive in the rain or drive through a puddle? its a truck not your laundry

 

I honestly laugh at people who complain about things like that. That scope is so much more important!!!! And to think...the actual maintenance of DoD equipment alone is about 80B per year. This is oil changes, tires, nuclear fuel rods, etc.. So you get the point. The people who complain about little things. They really just don't understand even after I try to educate them.

 

Car washes use pressure jets as do pressure washers. It rains and pours. There’s rain puddles and also slushy muddy snow treated with salt and ice melt chemicals. It’s going to have some rust, no way to completely prevent it. I don’t see how pressure washing could be any worse at hurting your truck than all that road grime. Maybe be selective when cleaning where you can. For instance, I wouldn’t pressure wash engine.

 

From my experience..I've been using 40° nozzle (2700 psi power washer) on that famous white paint and the undercarriage to clean, rinse+foam cannon for 4 and some years. Paint is still there and shiny, nothing was knocked off, cut or flooded, etc. Same is applicable to other 2 cars.

 

It's the scope and the supporting industries/technologies that flourish with mega huge projects like that. I just can't fathom the minds of people who are actively un-inspired by that stuff.

Anyway, pressure washing!... hahaha

 

You're fine. I pressure wash the underside of my truck on the way back from every wheeling trip. Only way to dislodge caked on dirt and mud from trail runs.