Washing frame on 1996 tacoma

Hello so I went mudding 3 months ago and took my tuck through a basic car wash with the undercarriage wash. I don't think it was good enough because there's still a sand like dirt all over and I think on the inside of the frame. How should I go about washing/draining the frame? Thanks

 

With a hose

 

I have one of these I use with my Generac pressure washer.

$20 M MINGLE Pressure Washer Undercarriage Cleaner, Under Car Wash, 4000 PSI (13")

https://www.amazon.com/Mingle-Pressure-Washer-Undercarriage-Cleaner/dp/B07K22DGRY

 

Immediately after finishing your mud mashing, sand sailing, and dirt darting - you wash it off with low pressure high volume water flow. Generally a round type flow works well.

After 3 months, do that for a while trying to direct water flow to everything as the force of flow will carry the stuff loosened by the chemical action of the water. Use some simple green (or simple yellow, or simple blue) to help.

 

Where do you use it, on the sidewalk? If you've a house in The City where you can wash your truck, we should be friends and I'll share my Christmas list google doc with you.

 

Thanks everyone