Fellow Freaksters,
I know this was covered before, but IMO it needs repeated attention with winter aproaching and very bad paint job Fit got from the factory!!
I purchased few cans of rubber undercoating in order to give more sound proofing against tire noise as a primary reason. Second was rustproofing.
Well, yesterday I got around rotating my tires so I used an opportunity to give wheel wells their ovedue attention.
I tried cleaning the surface with a plastic brush followed with a water/shampoo bath. Things got very clean, but I wonted it as clean as possible for undercoating to adhere, so I sprayed brake cleaner on stuborn spots and started wiping with a rag! Paint started coming off down to primer and finaly metal surface!!! The only thing that protects body paint is a very thin layer of clear coat, but not under the car! Every time you hear a smal rock hit your inner fender well and makes a metalic sound, rest assured it penetrated to the metal! That exposed spot will started rusting in weeks just from car washes alone. If you plan on keeping your car for more than a couple of years, protect your wheel wells or entire undercarriage with rubber undercoating!
Here is a few pics of final resuts.

 

so how effective was sound from wheels dampened after?

 

I just undercoated mine as well - last week. The results were impressive - a noticeable sound reduction. I undercoated the entire underbody as well.

What helped even more was adding carpet padding underneath the center console (it absorbs transmission noises), and adding batting material to the areas in the rear fender wells - between the metal fender and the plastic.

 

So far I am very content! Noise before had all frequencies represented, but now only low thumps when you drive over something. Do not get me wrong, if you would like it Acura RL quiet you need to Dynomat (or similar)entire floor, but this is a worthy improvement for $15 worth of undercoating! Tire and wind noise now comes more through closed windows than inside the car on most asphalt surfaces. Of course some roads are more coarse than others and you will hear them even in luxury cars. I drove over wet road with puddles and I did not feel like I was driving through a river! Only water noise came through the closed windows, again.
I'll give it some time, but I am sure I will end up going AppleMac*Fit route and work on inner fender wells on the back from inside the car. One day I might even gut entire interior and do full soundproofing like some fellow Freaksters.
Best of all I have a piece of mind when it comes to rust prevention, too!
My wife's Civic is next!
Ironically, I will be removing what I added to my CRX over 15 years ago as well as undercoating it came stock with for the sake of light weight. CRX is track bound! Can't wait!

 

Do you recommend any specific type of undercoating brand?

 

I did some googling on rubberized undercoating and I read that it works for a while until it starts to crack and water creeps in there and stays. Just a heads up.

 

I was going to do just my rear fender wells; only because the color of the car in the fender wells drives me kinda crazy. It rather it be camo-ed in.

I was just going to use some cheap spray bed liner stuff.

 

I do not have much experience with various brands. The one on the left has higher gas pressure in the can vs one on the right, so it sprays/covers better. One on the left has typical spray tip which is harder to hold and spray vs one on the right with a "pistol" grip. That "pistol" grip tip also clogged on one of the cans and I had to switch it with the one from identical can to use up the can to the end! One on the left is 18 oz. while one on the right is 20 oz. Final result is the same when it comes to actual compound.

Correct! Periodical inspection never hurt anyone! Two thiner coats are better than one thick one. Final result is pliable rubber, so common sense in maintenance is recommended. Anything for preservation of rubber will work. Looking at my CRX with 15 year's old job I did on it and no corrosion! Granted, I live in California away from snow. We do get plenty of rains in Bay Area!

That drove me nuts, too. Now shiny black color does! It will dull up soon.

 

Right, if metal is showing, clean it all up, scuff, prep, paint, then use the coating. Don't just cover the metal with rubber coating...

 

Brake cleaner? why would you use that? I know it is used to clean brakes, but it specifically says on the can that it should never come in contact with the paint. Brake cleaner will eat through your clearcoat and your paint.

 

I did not bother to point that out, but I have should have. You are spot on xorbe! I love using self etching primer. It just "bites' a bit better.


I run out of Goo-gone or what ever the name of the stuff was. There were some tar spots (lot of paving in the area over the summer) that I wonted off beside some other unidentified crap. I use brake cleaner as a last resort, but never on clear coat or painted body parts. Undercarriage, brakes, certain engine & trans parts,....yes. Spray on the rag, wipe, use shampoo, wipe and finally wax for protection if on unexposed painted underside. You are correct that it should not be used on painted surfaces in general and especially new water based paints manufacturers are forced to use for environmental reasons. Old, leaded paints were bad for environment, but were lot more durable and chip resistant.

 

if you need help with your interior work, let me know, I have a second car now (Honda Civic 2003 Hybrid) I can drive out there with my car on the weekends as needed =P