Fluid Film every year?

Yup, that body mount area is a salt and dirt trap. Both behind the mud flap, and inside it. It has drains holes, but dirt and mud can plug them up.

I pay extra attention to rinsing those areas out with the garden hose after a trip or in spring after the salt is done flying.

There’s a lot of little nooks and crannies like this, and only a frame nerd like me will care to find them all. There are a few threads that detail all those areas.

Oil changes, rotations etc take me forever because I usually end up distracted by doing a spot treatment here or there or just “inspecting”. I usually take my gallon bucket of wool wax and a brush with me whenever I’ going to crawl under it for maintainance. @djwantke is a kindred spirit in this regard…we’ve described it as feeling like michealangelo working on the cistene chapel.



The best thing for “normal”people to do is remove the spare and engine skid plates and then spray your favorite wet-film product liberally and thoroughly inside and outside the frame, crossmembers, and mounting brackets. Mind the cv boots and rubber bushings. Or pay a thourough person to do it). Then drive it down some dusty gravel roads to build a dry crust. Do this once, and forget about it.

(A previous post mentioned the gas tank straps. Guaranteed, in 15 years it will be hanging on by a thread if you don’t take care of the gas tank strap.)

As long as you make sure to regularly rinse the salt off the frame during warm spells or springtime, this treatment will buy you years and years of frame life. Some people don’t like the idea doing an underbody spray if you have a wet film, but since the wet-film cant be perfectly applied, I think it’s good to wash salt off regularly.

A thorough one time application won’t give you a perfectly rust free frame in 15 years, but it will be good enough. If you actually want perfect, it will need as much attention as a wood boat (no joke).

But, as they say…perfect is the enemy of good. The goal is to enjoy using the 4runner, and giving it a long service life by making sure the frame outlasts the body and the engine.

 

What do you use to spray inside of the frame’s boxed sections? I need to do a better job at that then just spraying in each hole.

 

Yes I used CRC Marine with similar properties on my Tacoma, which sees off-road use. However, I don't have any local shops that spray this, so it had to be DIY.

 

Ain’t that the truth lol I’ve learned all I know from McSpaz and the gang, if I’m honest


also me (favourite movie):

 

I did my 2023 this year and last year

 

Yes, DIY it

 

I used wool wax aerosol cans with the cheap little spray tube/ wand they sell for it. Good enough. Actually, I probably used some fluid film too because it creeps better. The cheap plastic wand doesn’t have a great spray pattern, and it gets messy leaks at the can…so I probably went through a lot more product than if I had a better wand.
I borescoped some of the holes last year…seems like I got decent coverage.

However, there are better “cavity wax” products on the market…I kinda like the look of the one that 3M sells. I think it’s an actual paraffin based wax. But a lot of those have pretty strong VOCs and should probably be applied with a paint respirator if you want to avoid a wicked headache. Fluid film isn’t noxious, it just smells like dirty wet sheep. And wool wax smells like…cleaner dry sheep?

 

LOL, that’s probably the face I make when neighbors look at me weird wondering why the heck I need to be under my 4runner constantly “working on it”.

 

Applied once and will re-touch every year. They asked me not to spray underside anymore.
I honestly don’t baby mine as you do. It’s a truck it better work when I need it. It’s always garaged and I am taking more precaution than what Toyota recommends.

 

I have used this kit for years.

https://www.woolwaxusa.com/Woolwax-Pro-Undercoating-Applicator_p_16.html

I only do frame internals every other fall now, as they stay pretty well coated.

 

Just an update. Got around to bringing it into the shop, $200 to reapply FF the 2nd time around, the original spray last year was $300. Worth it to me - no rattle cans, laying on my back, mess in my garage or driveway. Anyways he said it still looks brand new down there, not a speck of rust. For future record that’s 1 Michigan winter worth and 10,200 miles at the time of re-coat. Next time I’ll ask to go under and snap some pics just to post every year for comparison.

 

I had mine done with FF in Johannesburg Michigan for $170. But they did not remove the skid plate or lower the spare. They said they get good coverage spraying through the spare wheels holes. Dubious claim, but then I never checked. Maybe this summer, I did a quick look on each side after I got home and it did look good.

 

The spare is not bad to just crank down yourself and do that area. I also did the wheel on my spare with fluid film. That’s just more steel to rust.

 

If you really want to be thorough, remove the rear bumper skin and spray that area of the frame. I had my bumper off to swap valances so I used half a can spraying down all the metal covered by the bumper skin.

 

Johannesburg? I live half time in Lewiston... Surprised we haven't run into each other, I make my way to Vienna every now and then and never see any other 4R's around (well, a month or two ago I talked to some guy with a Green 4R at Glens but thats about it).

 

I live near Indian River, but went to Joburg to get my 4runner undercoated. There’s a place in Petoskey that does undercoating but was like 3x as expensive. Lots of 4runners and Tacomas up here, our local dealer is in Cheboygan.

 

It’s a small world I spend a lot of time with my family in Onaway and they have a place on Black Lake. It’s heaven up there for me especially being from down state. I get off at exit 310 from 75 in Indian River and get some Vivios pizza before going east. If I could just learn to catch more of the Burt Lake walleye life would be so much better

 

Big fish here!

 

Yep you got it.

 

I think I see a future meet forming....

 

I have the same kit, just touch back up in the fall. I set the woolwax bottles in warm water for awhile before I spray.

 

I was under the 4runner today and found a good example of paint separating at sharp corners and a weld beads. Even though it was all well coated with a woolwax crust, if the paint peels off on a corner, water gets behind there and starts rusting. This example shows why occassional inspections and touchups are a good thing if you seek perfection.

Pictured below, this is the spot on a bracket on the rear axle after I scrapped away the loose paint, and sprayed it liberally with fluid film spray (ran out of WW).