Underbody after a year of daily driving (pics inside)

[1Elvis]

Had the car in for the first service yesterday and while it was up on the lift, I thought I'd snap a few pics to document the state of the underside.

Date of registration: early March 2017 (built in Sept 16).
Mileage: 19,400 km (~12,000 miles).
Car spent about three weeks in a underground parking garage, but otherwise was always exposed to the elements. Daily driver, has seen quite a bit of rain and a little bit of snow.










Having seen how many exposed and untreated parts there are underneath the car, I can't help but wonder why Mazda won't put in the effort to make the Miata's underside a little more weather-resistant. I mean: Surely it would be cheaper for the customer if this was done at the factory. Oh well ... :/


E.

[Litfuse]

I noticed that the ND has been more susceptible to rust and erosion when compared to my MSM and NC. My ND has not seen rain or snow and I can still see rust forming on the welds on the chassis and suspension components. Not sure why. Oh, gram strategy...less paint, less weight. Lol

[Racing_Green]

Oh my. So glad I didn't buy an ND but now I have to decide weather or not to do the body on my NB. I could get a winter wheel and tire set for my new Giulia instead and have it wax oil treated.

[wolfgangdieter]

Steam clean or pressure wash the undercarriage. It doesn't look that bad. I don't see weld joint bubbling up with rust - usually the first to rust. My "bad chassis" rust basis is an older Toyota 4Runner - which I have had to wire brush, use rust removing acid on and repaint.

[Gord96BRG]

Originally Posted by 1Elvis

Having seen how many exposed and untreated parts there are underneath the car, I can't help but wonder why Mazda won't put in the effort to make the Miata's underside a little more weather-resistant. I mean: Surely it would be cheaper for the customer if this was done at the factory. Oh well ... :/

Hmm. I thought those pictures looked good, aside from the exhaust midpipe and the springs on the exhaust joint bolts, there was no visible corrosion. If you looked at an NA or NB with similar exposure, there would be a LOT more surface corrosion showing, of suspension arms, subframes, bolts, etc.

I sure wouldn't want a thick gooey coating of underseal all over everything on my ND!

[Richard Dekker]

Agreed...for an outdoor car, that's seen weather, they look fine. Exhaust components do rust due to not only being unprotected, but also going through many heat cycles which causes humidity to burn away or condense and being generally the lowest component under the car thus subject to wear from other causes.

[Mad Swede]

My reaction was the same. I thought it looks good for a year round driver.

[MX5TARGA]

Not TOO bad, but I'm glad I son't drive mine in the Winter!

Russ

[Mad Swede]

I thought I posted this, but I am wondering if they use mag chloride in Germany? That could explain the lack of rust. Makes a big difference, and they even put corrosion inhibitors in the solution. When I did the shocks on my '96 the various fasteners had only a relatively thin film of surface oxide on a year-round driver.

I guess sodium chloride (salt) is so cheap in other places that they can't justify the mag chloride solution.

[Cog]

Originally Posted by Mad Swede

I thought I posted this, but I am wondering if they use mag chloride in Germany? That could explain the lack of rust. Makes a big difference, and they even put corrosion inhibitors in the solution. When I did the shocks on my '96 the various fasteners had only a relatively thin film of surface oxide on a year-round driver.

I guess sodium chloride (salt) is so cheap in other places that they can't justify the mag chloride solution.

You did mention mag chloride in another thread, and it sent me to Google. Several sources claim that mag chloride is more corrosive than sodium chloride (see https://www.washingtonpost.com/local...=.51f9b1d08aa4 and https://www.codot.gov/programs/resea...components.pdf). So I wouldn’t put your hope on mag chloride.

[Werner]

Looks pretty good to me.

[wolfgangdieter]

I was in Germany years ago and they used to use fly ash from coal burning generating plants. Seems it contained sulfur (think sulfuric acid) when applied to roads. Sure did eat up Porsches and MBs.

[Werner]

Originally Posted by wolfgangdieter

I was in Germany years ago and they used to use fly ash from coal burning generating plants. Seems it contained sulfur (think sulfuric acid) when applied to roads. Sure did eat up Porsches and MBs.

AFAIK, ash is no longer used. Mainly salt is used nowadays. Usually a combination of crystals and solution.

[s5pitfire]

I had a bad feeling in my side seeing my brand new coilovers and under-body peppered with white salt after the City dusted the roads last winter (end of 2016) due to a 1" snow dusting. I tried to really spray my suspension behind the wheels at the 'wash several times and then gave up. You would need to put it up on jack stands, remove the wheels, scrub, and of course use a power washer.

[Blu 09]

Originally Posted by s5pitfire

I had a bad feeling in my side seeing my brand new coilovers and under-body peppered with white salt after the City dusted the roads last winter (end of 2016) due to a 1" snow dusting. I tried to really spray my suspension behind the wheels at the 'wash several times and then gave up. You would need to put it up on jack stands, remove the wheels, scrub, and of course use a power washer.

You would go crazy in wisconsin. The roads are as white as the snow from salt.
Occasionaly, i see a truck get onto the shoulder of the highway and create a salt dust funnel.
Its why mine sits in the garage until late March

[Mad Swede]

I wonder if the reduced corrosion here in CO is due to the climate then?

[gt40mkii]

Originally Posted by Gord96BRG

Hmm. I thought those pictures looked good, aside from the exhaust midpipe and the springs on the exhaust joint bolts, there was no visible corrosion.

I've wrenched underneath dozens of cars. I don't see anything out of the ordinary here.

Move along everyone. Nothing to see here...

[shocked by Bilstein]

What would be a real test is seeing the results of one winter from here in the midwest ! They use almost like a rock salt here. So far I've enjoyed driving the ND Club in snow instead of letting become a QUEEN . Its a real DD road warrior & I've got a picture album displaying what it looks like before washing . Warning the pictures are graphic

[Airport]

Looks about the same as our 9 year old Saab! Yet to have a good look under the ND.

[KevinK121]

Originally Posted by Mad Swede

I wonder if the reduced corrosion here in CO is due to the climate then?

I'm pretty sure your folks' climate is a little less severe, or at least I always hear about the snow melting pretty quickly when you do get it. We(MN) spend a few months a year where the temp rarely climbs above freezing. If it snows they salt. If it warms up and things melt a little, they salt. If they salt, they salt.

All this salt and I still see people that manage to find the ditch at least weekly.

[Cog]

Originally Posted by KevinK121

I'm pretty sure your folks' climate is a little less severe, or at least I always hear about the snow melting pretty quickly when you do get it. We(MN) spend a few months a year where the temp rarely climbs above freezing. If it snows they salt. If it warms up and things melt a little, they salt. If they salt, they salt.

All this salt and I still see people that manage to find the ditch at least weekly.

Going above and below freezing makes things worse. Higher temperatures encourage corrosion. If you have salt on your car, keeping it cold is better than warming it up.

Low humidity in Colorado might help. Swede also mentioned rust inhibitors, which might help as well.

[Mad Swede]

Another idea I have had, that may only work in our climate, is to run a fan under the car in the garage to speed drying out.

With all of the advances in design and materials, I am wondering if modern cars still rust out in the "rust belt" like they used to, or are folks operating on historical knowledge.

[Mattesa]

Where's the rust? Seriously I see nothing out of the ordinary or of any concern.

[1Elvis]

I guess I was a bit of a drama-queen last year...

I just had the car in for the 25,000 mile inspection and could take another good look at the underside. Sadly I didn't have my camera with me this time ...

If anything, the car looked better this time around, since I had just had it washed a few days prior and hadn't done any driving in the wet or snow since then (snows just melted away a few days ago over here). Even the exhaust didn't look as rusty as it did last year, probably due to temperature?


The mechanic commented that the car looked "great" for a non garaged daily driver.

The one thing that didn't look better are the brake calipers which have started to display very prominent signs of superficial rust about 10 or 11 months ago. Ugly AF, but not a safety-concern.

Oh, and yes: They definitely still do use salt on the roads over here. Sometimes they will also use sand/fine gravel, but salt is still very much a thing.

E.

[Mad Swede]

Someone mentioned setting one of those oscillating lawn sprinklers (the one that has a bar and shoots and swing from one side to the other). I might try to find one, but not sure if they are sold any more since a better mousetrap is always being offered. Actually, I do use the cheapy perforated head single point sprinklers that I could just move around under the car using the hose to get at everything. Might be better than attempting to shoot from the side like i currently do. Although not a daily driver, since I got the General GMax AS-05, they are almost as good as the XIce on the BRG, and I have cheated and driving around on light snow since I am so addicted to the ND.

I have been out driving since the last couple inches of snow, and am really impressed with those tires, not to mention their dry handling.