Anyone else noticing how poorly made the RX-8's interior plastics are as the car becomes older? I understand that touch points 15 years ago are not as nice as cars manufactured within the past 5 years, however I am astonished that early 2000's Mazda plastics were not improved from the 1990's.

My 65k mi (babied) RX-8 is going through a "refresh" after sitting for a good part of 3 years in a garage. Plastic pieces are simply falling apart as I (gently) operate them. As with most RX-8's, the passenger dash airbag cover developed a 3 inch crack even with religious 303 Aerospace Protectant application over the years and shade from the sun. The RX-8 plastics is no different from the notoriously crap-plastic FD RX-7's of the 90's.

In comparison, our 2013 CX-5 has zero issues with plastics falling apart and that is with 90k mi and zero shelter from the elements throughout its life. I would imagine Mazda changed their plastic formulation and added inhibitors/photostabilizers since the RX-8?

 

I blame it on two parts - Mazda specifications and how the parts were tested. Most parts supplier subject their parts to rapid UV testing (24-144 h of intense UV and heat in a light box with additional Arizona/SoCal testing of actual parts) and call that accelerated testing. They then take their experience and the accelerated testing and calculate the part will last 5-10 years of real exposure. Additional light box testing then adds on to getting something like a 10-20 year predicted life. They set their specs to the accelerated testing without actually performing actual testing on that and previous models for the life of the car or the life of a model car. We do it for package parts at my job at a Fortune 100 consumer goods company only making changes as we get consumer feedback and learn more.

The issues come with resin supply issues, variation, stability additives, and real-world conditions that cannot be testing under accelerated conditions.

 

Have you seen other brands' interiors?
My 17 years old 8's interior is in way better shape than any of the same age competition.
An audi a3 I had was a pos. Roof lining hanged, the plastics color faded. BMWs of the same age? Crap.
Mercedes? Crap. All had faded color plastics, roof lining hanging. The 8? Roof still like new. Color is mint. No fading. At all. All switches in place. Everything clicks like it's supposed to do.
THe only problem is the passenger airbag dash crack. Big deal. And it's not some garage queen. I smoked, I am fat, it was left on the sun for quite some time. It still stands.

 

Yes I agree with the positive sentiment. 2 rx8s, both with almost 200k each and a 2006 Mazda 3 with 300k.

I thought the interior quality has been excellent, except the airbag cover. Cloth seats all around and excellent wear overall. Quiet, too.

 

The airbag cover problem might be less about the platic itself but more about the metal bits on the underside working the plastic with heat expansion.

 

Your awesome this response made my day lol thanks haha

 

I agree, interior quality is definitely holding up over time. I've been in plenty of neglected junk yard RX-8s and the interiors are usually in good shape minus the airbag cover and sun visors.

 

The interior is mine is like new condition. Even the leather seats are holding up fine. I can't say the same for my 3-series that that has started to crack on the driver seat.
Both are parked inside garage.
Often neglected but really crucial is lubrication of your rubber seals (trunk, doors, sunroof, window etc). I use baby oil and dielectric grease.

 

Definitely for sure I've noticed (along with it being really hard plastic). Despite being in great condition- they seem to age badly.