What to use to increase life of parts and protect from weather and salt?

Joined
Aug 22, 2009
Messages
6,284
Location
Pittsburgh,PA U.S.A.
Pittsburgh is one of the cities that uses a lot of salt on the roads in the winter. And even with our recent mild winters they still manage to use enough of it that for a month or more most cars all have a dirty white/gray coating on them. Some weeks it seams useless to even try to clean a vehicle because of it being so cold, and or because so much salt is being used that the vehicle would very quickly become coated with salt again.

Some on BITOG suggest to get a long life out of my CR-V I should protect the CV joint, axle, flex pipe, etc of the vehicle from the salt and weather. I have had it sprayed by a rust prevention company and part of there deal includes bring it back every year for 6 more years for touch-up.

I painted the coolant cross pipe and oil dip-stick with Rust-Oleum Zinc spray paint that I sprayed into a can and brushed on. I had to mask the entire area very well. That stuff splatters everywhere when you brush it on. I ended up with a bunch of rags with little silver specks on them. Though I did not unmount the alternator and R&R the bracket that prevented me from being able to paint some area of the coolant cross pipe.

1) What should I spray on the CV boots?

2) What should I spray on the flex pipe? Please keep in mind how hot that gets.

3) What to treat the axle with? I am thinking that maybe I should spray it with Rust-Oleum flat black.

4 a & b) And what other areas should I treat? And with what?

I probably could come up with something to put on the CV boots, but my choice might not be the best. But it is tough to figure out what will actually protect and stay on the flex-pipe for a while with all that heat. For that one the only thing I can think of is WD-40, but that is flammable until the solvent used to carry it evaporates away, and would wash away if water from rain hit it, and I don't even know if it can handle heat.

Thanks for any suggestions.
 
Last edited:
I had a 4Runner that spent 22 years on salt encrusted roads every winter. No rust, or cv boot deterioration. I simply washed it with plain water as often as necessary to keep the salt off.
Have you checked the frame recently. My brother has one maybe 16 yr old and it looks great but frame is severely rusted and no longer safe. They sell a few steel repair pieces for the 4Runner frame. So it may have some issues.
 
Pittsburgh is one of the cities that uses a lot of salt on the roads in the winter. And even with our recent mild winters they still manage to use enough of it that for a month or more most cars all have a dirty white/gray coating on them. Some weeks it seams useless to even try to clean a vehicle because of it being so cold, and or because so much salt is being used that the vehicle would very quickly become coated with salt again.

Some on BITOG suggest to get a long life out of my CR-V I should protect the CV joint, axle, flex pipe, etc of the vehicle from the salt and weather. I have had it sprayed by a rust prevention company and part of there deal includes bring it back every year for 6 more years for touch-up.

I painted the coolant cross pipe and oil dip-stick with Rust-Oleum Zinc spray paint that I sprayed into a can and brushed on. I had to mask the entire area very well. That stuff splatters everywhere when you brush it on. I ended up with a bunch of rags with little silver specks on them. Though I did not unmount the alternator and R&R the bracket that prevented me from being able to paint some area of the coolant cross pipe.

1) What should I spray on the CV boots?

2) What should I spray on the flex pipe? Please keep in mind how hot that gets.

3) What to treat the axle with? I am thinking that maybe I should spray it with Rust-Oleum flat black.

4 a & b) And what other areas should I treat? And with what?

I probably could come up with something to put on the CV boots, but my choice might not be the best. But it is tough to figure out what will actually protect and stay on the flex-pipe for a while with all that heat. For that one the only thing I can think of is WD-40, but that is flammable until the solvent used to carry it evaporates away, and would wash away if water from rain hit it, and I don't even know if it can handle heat.

Thanks for any suggestions.

What product did you have sprayed for rust prevention. Please don't me Ziebart.

As for the CV joint I think they mainly get cuts and tears from rocks or ice being thrown up. I would not spray them with anything. But if you inspect they regularly you may catch a cut or tear before much dirt gets in and then just replace the boot vs CV joint.
 
  • Like
Reactions: JC1
Coated rotors when you need new brakes :)

The rust prevention you;re already doing will go a long way. When you do need a new exhaust, get something stainless.
 
Have you checked the frame recently. My brother has one maybe 16 yr old and it looks great but frame is severely rusted and no longer safe. They sell a few steel repair pieces for the 4Runner frame. So it may have some issues.
When I sold it, it was rust free. Including the frame, inside and out. Throughout my 22 years of ownership, I would periodically check inside the frame rails with a bore scope, to make sure my efforts were effective.

Any vehicle made of steel will rust in a highly corrosive environment, if neglected.
 
What product did you have sprayed for rust prevention. Please don't me Ziebart.

As for the CV joint I think they mainly get cuts and tears from rocks or ice being thrown up. I would not spray them with anything. But if you inspect they regularly you may catch a cut or tear before much dirt gets in and then just replace the boot vs CV joint.
The company I used is called RRI and that stands for Rust Repair Incorporated. Much of there business is about repairing vehicles that have already rusted. Often people with vehicles that will not pass inspection because of rust use them. They do not do body panels. Basically rusted sections under vehicles. And there oil/tar like coating they use seams to be a good product. I figure most of there work is repairing rust, they know a thing or two about where vehicles will rust and how to prevent it. You have to pay for the labor of them cleaning away any rust before they will coat the vehicle if it is not a new vehicle. And the deal for the coating includes bringing it back every year for 6 more years for touch-up already paid for in the initial deal.
 
Why would you protect your axle? Has an axle ever rusted out and snapped in half?

I'm not sure what your fetish is with the coolant crossover and dipstick among all the stuff under your hood. Once you hit 5-6 years there's usually enough oily mist that your engine's protected anyway.

If you want to pay attention to something, check out your battery, tray, hold down, and whatever's underneath it. I've had many cars where the subframe is visibly and obviously worse under the battery vs the other side. Granted, the other side is on the engine pulley side of things and probably gets a little oil spray. But battery acid is corrosive and insiduous in that it eats frames from the inside-out.

As for the axles and undercarriage, I like the idea of oil-wax sprays. I use fluid film-- get it by the gallon, use about 1/3 gallon per car per winter. The applicator costs $15 and uses my garage air compressor. If ziebart is an oil, and not a rubberized product, go for that.

I do keep cans of rubberized undercoating around, but it's for beaters. Sometimes I have to cover rocker panel holes to pass inspection, other times it's a little stretch of subframe. I don't have the resources of OEs, and the rest of the car is often a year or two out from the junkyard anyway. So I pop_rivet in my patches and hose the mess down with caulk, bondo, flat black paint, and rubberized undercoating. New car? No way.

BTW cold dry salt is fairly chemically inert. The worst corrosion happens when it's just above freezing, foggy everywhere, and that salt's still stuck to everything on your car.
 
Really you'd just need to wash it, if your getting it sprayed yearly then it shouldn't be a problem, Personally, I use fluid film to undercoat my personal car, any product sprayed on the pipe is gonna get burned off anyway.

Also, avoid using rubberized undercoating, once it gets a small chip it holds in moisture and will destroy your frame faster than if you didn't have anything on it.

if your really picky get some fluid film and spray the inside of the frame as well, drain holes in body panels, as well as other small cracks as crevises that the shop might have missed.


mainly just wash it regularly and you shouldn't have any issues.
 
Pittsburgh is one of the cities that uses a lot of salt on the roads in the winter. And even with our recent mild winters they still manage to use enough of it that for a month or more most cars all have a dirty white/gray coating on them. Some weeks it seams useless to even try to clean a vehicle because of it being so cold, and or because so much salt is being used that the vehicle would very quickly become coated with salt again.

Some on BITOG suggest to get a long life out of my CR-V I should protect the CV joint, axle, flex pipe, etc of the vehicle from the salt and weather. I have had it sprayed by a rust prevention company and part of there deal includes bring it back every year for 6 more years for touch-up.

I painted the coolant cross pipe and oil dip-stick with Rust-Oleum Zinc spray paint that I sprayed into a can and brushed on. I had to mask the entire area very well. That stuff splatters everywhere when you brush it on. I ended up with a bunch of rags with little silver specks on them. Though I did not unmount the alternator and R&R the bracket that prevented me from being able to paint some area of the coolant cross pipe.

1) What should I spray on the CV boots?

2) What should I spray on the flex pipe? Please keep in mind how hot that gets.

3) What to treat the axle with? I am thinking that maybe I should spray it with Rust-Oleum flat black.

4 a & b) And what other areas should I treat? And with what?

I probably could come up with something to put on the CV boots, but my choice might not be the best. But it is tough to figure out what will actually protect and stay on the flex-pipe for a while with all that heat. For that one the only thing I can think of is WD-40, but that is flammable until the solvent used to carry it evaporates away, and would wash away if water from rain hit it, and I don't even know if it can handle heat.

Thanks for any suggestions.
LPS 3 works well for a long-term soft waxy film for metals.
 
You mention some tough spots to rust proof. The axle spins and will throw off any rust proofing (and probably most Of your salt and water too, which is good).

But the CV boots I’ve sprayed annually with silicone. Does it help? I hear it keeps them supple and prevents tears, although I doubt it.

I use fluid film on my undercarriage twice a year. Works ok. But it isn’t great with wash off, a few that might be better is CRC marine, cosmoline, or anything that can leave a wax like finish. I’ve used white lithium grease on high traffic spots underneath and it sticks and rust proofs really well. I’ve used regular grease too. Know what has been tested to work well with rust and good at preventing run off? Anti seize. Yup, doesn’t wash away easily and is excellent at preventing rust. Consider that for your axles maybe. Or white lithium grease (you want something that will not been thrown off). And honestly, anti seize might be your best bet on exhaust...I believe it’s pretty heat resistant, but don’t quote me on that.
 

What to use to increase life of parts and protect from weather and salt?​


In 2005 we used the money we got from selling our house and small business and moved to Arizona. Rust hasn't been a problem since, though sunburned paint and tires aging out instead of wearing out are different problems. We lived NE of you in Brookville and DuBois so I know exactly what happens to vehicles. The joys of working under vehicles of any age with zero rust can't be overstated.

Seriously though, there wasn't anyone around there that was applying any kind of underbody protection, are there places that do it in the 'Burgh?
 
Really you'd just need to wash it, if your getting it sprayed yearly then it shouldn't be a problem, Personally, I use fluid film to undercoat my personal car, any product sprayed on the pipe is gonna get burned off anyway.

Also, avoid using rubberized undercoating, once it gets a small chip it holds in moisture and will destroy your frame faster than if you didn't have anything on it.

if your really picky get some fluid film and spray the inside of the frame as well, drain holes in body panels, as well as other small cracks as crevises that the shop might have missed.


mainly just wash it regularly and you shouldn't have any issues.
Yeah, I’ve personally been doing the fluid film applications for a few years now and it does help slow down the formation of rust, not perfect, but it helps. I do it twice a year.

For the higher traffic spots under a car/truck, I’ll manually apply a light coating of white lithium grease. Another product similar to Fluid Film is New Hampshire Oil Undercoating...goes on maybe a little thicker and it’s black. I see franchises popping all over the place in New England...Maine, New Hampshire.

With the fluid film I’ll even spray under the hood in spots...strut towers, hood latch, inside the fenders. I like to get into all the doors and frame. Inside the bumpers, inside the hood itself, up on top of the gas tank, in front on the radiator support and inside of the cradle.
 
I used to use Fluid Film but IMO it’s just not up to snuff, not if one drives a lot—washes off too fast. I also moved and now have a garage that is all but heated, and boy did I notice a lot of rust after just one winter. The car went down hill really fast. If kept outside maybe it would have done better. Anyhow. If you drive enough that you have to do a tire rotation during the winter, you might have to reapply FF, I found myself doing that in the winter time.

I’m not sure that CV boots need anything. Flex pipes, too hot to treat. Maybe you could paint them but I suspect the paint would flake off. But the flex pipe should last years before needing replacement, and then it should be a cheap repair.

[I have heard of axle shafts rusting out. I think our Civic did that. I was not into DIY at the time so I don’t know why it stopped moving, one tow to the dealer and it got a new axle. Years later Eric O on South Main Auto had a video showing a… Civic with a rusted axle. Apparently Honda had a rubber dampener on the axle, and yep, acts like a salt trap.]

On my ‘99 Camry with failed clearcoat, I elected to use Rustoleum Rusty Metal Primer to touch up rock chips—looks awful but so does the car. 4 years later those chips haven’t grown. I just used some underneath another car and I’ll be interested to see if it holds up.

I’m also thinking of switching to RP342 to see if that can hold up better (side note, stuff really stinks, spray it outside! At least it seems to stop smelling quickly).
 
I use a lawn sprinkler. But if you have a pressure washer...


be careful with a pressure washer and an old/older Rust Belt car.

Went through a car wash once and the pressure was the final straw for the steering fluid return line. Felt it immediately as I drove out of the dryer.

As for OP's flex pipe. The point of failure, besides a rusty flex pipe, is that the bolts will rust on to the assembly. No big deal for any competent muffler shop....they'll just cut out the flex pipe and weld on a new one. mine only cost $85.

But if you want to avoid brut-forcing the pipe, check on those bolts/gasket once a yearwhen you're under the car. And if those bolts are still good, when time comes to change the flex pipe you'll only have to unbolt the section versus a cut-weld.

another place to watch once you get up there in miles is the donut exhaust gasket, between the engine and the start of your exhaust. guessing that there is no way to prevent rust there beyond washing away the salt in the winter. (but we are talking 10+ winters)
 
Jim, you're on the right track. Painting things like the brackets and tubes you list will keep them looking prettier for longer. Are those a huge risk for rusting right through?

In terms of the CV axles, like said, because of the flexing and movement, there's not much you can do.

Coating/painting the exhaust flex pipe is much the same. Too much heat, movement, etc. for a coating to stay put and/or actually do anything positive for you.

I've been using Woolwax and FluidFilm on my vehicles and a product called rustbullet for a paint-over-rust product if need-be. On my 2019 Ram 1500, it's still a slick greasy mess underneath in areas that don't see direct road blast, and it's been about a year since I treated it.

Like supton mentioned above, road blasted areas will shed oil coatings over time. Some like Krown insist that magical properties still remain even though it's not greasy to the touch, but yeah... I dunno.
 
OE CV boots are made from thermoplastic and don't need any maintenance other than an occasional rinse. They should be pretty sturdy over the life of the vehicle. When they do fail, it's usually from physical damage, or improper suspension geometry such as lifting or lowering. Usually it's only the boot that goes wrong, the axle itself only fails when enough grit has gotten inside to deteriorate things mechanically.

The problem is, it's usually cheaper to slide in a replacement aftermarket axle then it is to properly do a re-boot due to the labor. Not to mention that OE boots are hard to find and could cost as much as an entire aftermarket axle. Almost all aftermarket axles use neoprene boots instead of thermoplastic, which is vastly inferior and might only last a few extra years. Neoprene quite literally degrades in ozone.
 
Back
Top