Folks-
Just purchased a sweet pearl white (black interior) '23 GX with 20k miles. (1 owner, clean car fax, Lexus service, etc...).
Looks like it was garaged and no issues inside as well.
We don't plan on off roading but we do enough driving (Northeast...), all year, that the excessive salt treatments, etc. has me concerned about the undercarrriage.
I've heard about Fluid Film....any other suggestions???

Thanks again!!

 

Wool wax, Fluid Film you will hear the most.

i have Fluid Filmed my 4Runners and the GX for years - my hands get dirty when working on them but I have no rust issues. I live in NE Ohio where salt and brine can be applied to roads 6 months a year.

 

I ended up with Cosmoline after trying the snot-based films that always stay wet.

 

This YTer goes indepth about each product on the market is good and bad etc etc.
https://www.youtube.com/@RepairGeek

My personal recommendations are:

1) Any undercoating is better then nothing, and nothing is better then rubberized undercoating.
2) First application, best to get it done at a shop, they have all the tools, should be $500 max. Ask them if they can remove the heat shields, spare tire (you can do this yourself before you go in), and all tires (as a courtesy you can get do a 5 wheel rotation since the tires will be off) before they spray on a lift. You ideally want to go in with a clean frame, and ideally rust scale removal, but an undercarriage wash is also acceptable (not ideal but better then nothing).
3) If you want to use what Toyota used after replacing those broken Tacoma frames, Noxudol is the brand. However they are not cheap.
3) Annually or when needed DIY touchups with a rattle can.

 

I used amber translucent Cosmoline RP-342. It also comes in black color.

 

I've used Ziebart on multiple vehicles living in New England with no rust after 27 years max.

 

Did Woolwax at a shop last summer in my 2021 when I bought it. I would go with either woolwax or fluid film. Shop closest to me used Woolwax so I went with that.
They did tell me Woolwax has a new product that is one and done permanent solution if you want to investigate that. They claimed it does not trap moisture. idk - i am not guinea pig, I bought a car 10 years after it first debuted!! ;-) I went with the standard product.

 

Woolwax and Fluid film run the same cost wise from research. NHOU I have not, but there the big up near OP i believe.

That new product, by any chance is it called Boss wax?

Edit Boss wax is NHOU.

 

I don't think so. But honestly, I do not remember. All I remember was that it was a new product and not strictly for new cars, mine being 3y old at that time.

 

Both my friend and I did undercoating on the same day at his place (he has a compressor). I purchased the kit from woolwax. He had a sprayer kit and purchased fluid film. For me, wool wax was a win. It barely smells and for that reason, I would choose that. My friend complained for several weeks that his garage smelled.

EDIT: BTW, I just did a post winter under-carriage wash and Car Pro Reset wash and wax as well as changing back to all seasons and checked my undercoating 1.5yrs later (untouched) and couldn't spot any rust. I'm in Toronto, so definitely the rust belt.

 

For 11 years I climbed under my Tacoma each Fall and sprayed FF. It helped a lot but when I sold it rust was starting to form along the door sills and a few other places from the inside of the body out. Places I couldn't get to. Frame on the outside was decent but far from perfect.

Picked up a 19 Lux a year and a half ago that had spent winters in Texas and summers in Mn. so had never seen salt. Got it right before winter so dropped the spare and cleaned the under carriage and took to a NHOU shop that recently opened near me.



After watching him apply the NHOU oil I will never do it myself again he got into places I never thought of. Including pulling drain plugs and changing pressure on the wand and swapping out tips. Now that I am knocking at the door of 70 I am getting too old to be doing that crap anyhow. Getting under the rig isn't bad it is the getting back up that hurts LOL.



NHOU oil is FF that DuPont put on steroids. A year and a half later it is still creeping UP in places defying gravity. Reminds me of Kroil penetrating fluid. It has much better staying power than FF as well. The NHOU Boss Wax one and done is only for new vehicles they will not apply it to vehicles that have already seen salt of I would have had that done.

The guy that did mine moved back to Erie, Pa. said it was too cold here in the winter. Something about it isn't bone chilling cold it is bone breaking cold. Kind of ironic as Erie, Pa. usually wins the Golden Snow Globe title most years. Not sure what I will do next year as NHOU is more a NE thing and not many of them around these parts. But when Fall comes around this year even if I have to drive a day or so each way I will have NHOU applied again.

 

My experience is, first, anything is better than nothing. Second, Lanolin based rustproof products seem to be good choices, such as Woolwax and Fluid Film. They are breathable, do not trap moisture under. They last a few years so one has to check and re-apply every few years.

 

I second the ziebarts. I lived in central NYS for 6 winters, drove a 80s Toyota pickup from So. CA. First thing I was told to do was go to Ziebarts and have the frame/body treated. After 5 winters, the only part of the body that corroded was the tailgate. I only treated the car once and seldom washed it. Body seams that were notorious for corrosion on these trucks didn’t rust, no rust on doors where untreated cars would have massive corrosion at the bottom of the doors. I have no idea how much they charge these days.

 

I used AMSOIL heavy duty metal protector first , let it dry and the went over it with cosmoline rp-342 black .

 

I went the FF + Cosmoline route on my new to me '23 Lux. Purchased in MD at Sheehy Lexus as a CPO with 14k miles. Had it done at Carson Undercoating which if you're in the St. Paul/Minneapolis area I highly recommend them. Dropped it off on a Sunday night and picked up Wednesday morning. Only one small FF drip all summer on the garage floor.