Thanks for information! I now have an appointment scheduled with the shop. TheyX3 here.
I live in WI, and frequently drive in Chitcago area road salt. I've done fluid film for many years and IT WORKS! It's the only thing (along with wool wax) that creeps without drying. $389 for initial and $89 for yearly touch ups is a great price!
I bought my own professional gun about 15 years ago and have applied numerous gallons of fluid film over the years. The last vehicle I took care of with it, put tons of miles on, and then sold was a 2007 Yukon Denali. It looked brand new still underneath, the buyer was amazed.
Done properly, you should have a good, thick residue on the entire frame, underbody, inner fenders, doors, etc. A good shop will pull body plugs for access, make sure the clamps around your rear A/C lines are coated well, brake lines, fuel lines, etc.
You will need to have a touch up yearly on the frame rails, most everything else will repel the water and salt. I rarely have to refresh doors, fenders, or underbody. I will CAUTION you against excessive washing. The harsh soaps can dissolve the coating. STAY away from undercarriage washes as well because all they do is blow the crap UP into the body and do more harm. Not to mention a lot of washes by us are required to recycle water, which ends up washing your vehicle in salt water.
Sorry for the long winded explanation, but after working on rusty chit for years in shops, I have a real passion for keeping stuff nice. Not to mention the value in it based on new car prices.
Spray the entire undercarriage, inner and outer wheel wells, through the hood, trunk, and all doors. They don’t drill any new holes, They send their wands through pre drilled drainage holes made at the factory.
I have read that I need to avoid any type of undercarriage wash once applied and only wash the undercarriage in the summer months.