Undercarriage Rust

:
2017 CX-5 GT
Recently I had taken my 2017 GT for a routine oil change and maintenance at 15700 miles to the dealership. While waiting for completion of service, the tech sent me a video text showing and declaring all looked well under the car. However, I noticed several rust spots (see attached pic). I live in the NE dealing with snow, ice, and salt seasonally. Is this amount of rust an issue, or could be one long term? Will appreciate any insight on this matter. Thanks.
 

Attachments

  • 2017 CX5 Undercarriage.jpg
    2017 CX5 Undercarriage.jpg
    61.7 KB · Views: 617
Recently I had taken my 2017 GT for a routine oil change and maintenance at 15700 miles to the dealership. While waiting for completion of service, the tech sent me a video text showing and declaring all looked well under the car. However, I noticed several rust spots (see attached pic). I live in the NE dealing with snow, ice, and salt seasonally. Is this amount of rust an issue, or could be one long term? Will appreciate any insight on this matter. Thanks.
What do you consider long term?
 
Upvote 0
Recently I had taken my 2017 GT for a routine oil change and maintenance at 15700 miles to the dealership. While waiting for completion of service, the tech sent me a video text showing and declaring all looked well under the car. However, I noticed several rust spots (see attached pic). I live in the NE dealing with snow, ice, and salt seasonally. Is this amount of rust an issue, or could be one long term? Will appreciate any insight on this matter. Thanks.
There’re plenty of rust complaints on Mazda CX-5 either under-carriage or interior, especially from snow-belt area. Many CX-5 owners in Canada suggest rust-proofing when they purchased a new CX-5. Since you live in the NE and owning a string of Toyotas, see the very last example at the bottom.

Would you be concerned about this amount of rust?


Just joined the club and question on rust

Rustproofing & Undercoating...is it necessary?

Plenty of rust complaints on suspension、undercarriage、and brake calipers:


I'll try and post some pics of my rear brakes soon. It's not just the rotors either. The calipers and brackets are rusted badly as well.
Same as gazelle said too: never happened like this on any of my previous cars.


I was very surprised at the amount of rust in some areas but the dealership mechanic assured me it is normal. ⋯
Photo of the rust I was talking about:

View attachment 234064View attachment 228722

Another recent very rusty undercarriage after two or three years from a CX-5:
IMG-2c99bd26eabdc6225a9cf42358658060-V.jpg

previous year, un treated.
North east US.

I dont honestly believe Mazdas have good rust resistance even today. yeah may be better than 10 years ago but not the best.

This CX-5 should be from Illinois:
Just spent 3 hours under my 3 year old CX-5. Did AT, Engine and 2x TC oil changes.

Rust level in various spots on 36 month car was tad too much. Mark this post, but in 4 season weather I don't see this version last 10 years.

If this is CA/FL type of no salt climate - all should be fine, but winter states beware.

This CX-5 is from Toronto area in Canada:

Here are comparison pictures between his CX-5 and Toyota Matrix from Southern New Hampshire:
Rust like that after a few years even with heavy use of salt I believe is unacceptable with today's coatings and materials to look worse than a car that is 13 years old is not acceptable. How can Mazda get away with this? I love how this car drives and looks but also want one that will last. Also very happy with fuel economy so far getting around 30.5MPG on my 100 mile round trip commute.

2005 toyota matrix/pontiac vibe - 225K miles driving 100 miles a day
attachment.php

View attachment 216618

2014 CX-5 (seen 2 winters) -28K miles
attachment.php

attachment.php

View attachment 216616
View attachment 216617
 
Last edited:
Upvote 0
I regularly see 1st gen CX-5s (2013-2016.5) year round here. I also live in an area that regularly sees ice, snow and salt for what seems like half of the year. It seems the rust is primarily a cosmetic issue. As far as I can tell, nobody has complained about the subframe or suspension components rusting through and failing - only that it looks bad.

To be fair, I have seen other vehicles with undercarriages that do not have that level of surface rust, so there is definitely still some room for Mazda to improve on that aspect. But nothing that would indicate a long term problem IMO. As a precaution, you can do an annual Fluid Film treatment to inhibit the rust and attempt to prevent it from looking any worse, or treat the rusty areas with POR15. But I personally think you have nothing to worry about :)
 
Upvote 0
We have the same problem of rust here in Sweden with cold icy winters and salt on the road. Some European cars like Volvo, SAAB, VW have good rust protection. Unfortunately the Japanese cars are rather devoid of rust protection. Reliable but rusty! I had my cx5 treated the first year itself and that cost me 500 euros. I think it is worth it. I tend to keep it for at least 10 years. I thought the Canadians were quick on rust protection for their cars.
 
Upvote 0
I owned a 2003 Chevy Tahoe that I just sold. The 1st owner had it 9 yrs and it saw its share of crappy weather and salt, but the last 9 yrs that I owned it, it rarely ever got out of the garage, much less got wet or salty. The 1st owner had the Tahoe rustproofed by having a rubbery protectant sprayed on it’s underside. That rustproofing material began to peel away from the surfaces it was supposed to protect. Then water and salt would get trapped between the rustproofing and metal thereby accelerating the rust on the belly of the Tahoe. Maybe the rustproofing material was improperly applied, but it sure left a sour taste in my mouth for rustproofing.
 
Upvote 0
For DIYers fluid film is very effective. It does wear off from driving in water and snow, I spray here and there at the same time I change the oil. You have surface rust. You can stop it from rusting any further with fluid film, spray right over the rust. And like P-51 said, the thick tar like undercoatings can be problematic. There are a ton of videos about it.
 
Upvote 0
My method of corrosion protection is to avoid taking my CX-5 out in the rain or snow. When the weather is bad, we take our 2009 Honda Civic. It’s the sacrificial lamb. You pretty much have to be retired and not have a life to implement this method of corrosion protection, but it works. Living in Illinois, toward the end of the snowy weather, sometimes the road salt is thicker than the skiff of snow received. Gotta use up the salt so new contracts can be negotiated with politically connected venders. Illinois - uggg!
 
Upvote 0
My method of corrosion protection is to avoid taking my CX-5 out in the rain or snow. When the weather is bad, we take our 2009 Honda Civic. It’s the sacrificial lamb. You pretty much have to be retired and not have a life to implement this method of corrosion protection, but it works. Living in Illinois, toward the end of the snowy weather, sometimes the road salt is thicker than the skiff of snow received. Gotta use up the salt so new contracts can be negotiated with politically connected venders. Illinois - uggg!
I am close to doing the same thing except I am working but use my company car in bad weather.
 
Upvote 0
In the winter time, if you just squirt (not wash with soap and water) the snow and salt off your car, including the underside, it will go a LONG ways to warding off premature rust. Do it ASAP. That only costs you your time and a little short term discomfort. I’ve never had a heated garage. I just do it in the driveway. It is better if you run hot water to your garage so you can hook your hose up to it. That way the water doesn’t immediately freeze on your car if it’s 20° out. It helps to keep your hands from freezing too.

As evidence that this cheap method of corrosion protection works, consider this. I owned an 81 Celica GT for 32 yrs. It was my daily driver for 20 of those years. I’ll admit that I babied it, but It had 188,000 mi when I sold it, so it saw it’s share of bad Illinois weather. However, it had about 1 square inch of rust (collectively) on the whole body when I sold it because I kept it clean and hosed off the salt and snow as soon as possible. I don’t think there was any rust on the underside except bare metal parts. If any of you are familiar with the early Japanese cars, you know they were prone to premature rust, especially here in the Rust Belt.
 
Upvote 0
Hit it with rustoleum gel, clean it and spray some flat black paint on it. I just bought a used axle because the boot in mine ripped and it came from a rust area.. cleaning up now with rustoleum then throwing paint on it.
 

Attachments

  • 20210529_153635.jpg
    20210529_153635.jpg
    127 KB · Views: 133
Upvote 0
Back