Piston Slap: The Final Carbon Fiber Nail?

Sajeev Mehta
by Sajeev Mehta
piston slap the final carbon fiber nail

TTAC Commentator gimmeamanual writes:

Hi Sajeev,

The recent article about the carbon fiber subframe by Magna and the comments predicting vehicle life-ending failures got me to thinking — in the last 10 years or so, has any automaker introduced an innovation or major shift from the norm that resulted in repair costs so expensive that the vehicle would be better off scrapped inside what one would consider its prime service life (say, 10yrs/100k)?

It seems we’re often too ready to predict gloom (turbos exploding, unrepairable aluminum trucks) and not give the engineering teams the credit they deserve. Yeah, some technologies do suck in execution, like the Focus DCT, but they don’t result in scrapyards filling up with otherwise pristine examples.

Sajeev answers:

I doubt such an innovation exists, the “drive vs. scrap” decision is often a death by a thousand cuts, not a single item. And it’s not necessarily about the engineering; more about modern automotive recycling operations.

But it depends on the vehicle’s design, parts availability and unique living conditions after driving off the showroom floor. A fully-depreciated Audi A8 with a trashed interior and electrical faults will likely donate itself to your next cooler fulla beer/soda cans. But damn near any 7.3-liter Power Stroke Ford with a blown motor? Someone will fix (and flip!) quickly with recycled parts.

To wit, carbon fiber subframes on a mass-market vehicle will also utilize the automotive recycling industry to ensure a good stock of perfect parts from flooded/rear ended/otherwise trashed examples. Sure, it’ll be more to replace than pulling out the kinks in a Camry’s metal subframe, but the threshold for being a complete write off might be higher than the naysayers suggest.

Most subframes are bolt-in, and I certainly don’t see Ford trying to weld carbon fiber to a metal unibody. So if Ford pulls the trigger on their upcoming 2020-ish sedan, don’t wreck one in the first two-ish years without comprehensive insurance. But in the year 2025? Expect junkyards well-stocked with used CF subframes, ready for shipment to your nearest body shop for bolt-in perfection.

I don’t see the doom and gloom equation. I see our automotive recycling ecosystem ready to take on this technological wonder on a large scale implementation. Off to you, Best and Brightest!

[Image: Magna]

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

Join the conversation
3 of 23 comments
  • Slap Slap on Apr 27, 2018

    The problem using a salvage carbon fiber subframe is that it can be damaged yet look fine to an observer.

  • Goatshadow Goatshadow on Apr 27, 2018

    What are repairs on 8-9-10-speed transmissions like?

    • Jack Denver Jack Denver on Apr 27, 2018

      Automatic transmissions were always complex devices. Adding a couple of more planetary gear sets makes them slightly more complex (and expensive) but not by a lot. What is more important is that the transmission is a solid design and sized properly for the application. You can have a 4 speed auto that is totally unreliable or an 8 speed that is rock solid.

  • Ollicat I have a Spyder. The belt will last for many years or 60,000-80,000 miles. Not really a worry.
  • Redapple2 Cadillac and racing. Boy those 2 go together dont they? What a joke. Up there with opening a coffee shop in NYC. EvilGM be clowning. Again.
  • Jbltg Rear bench seat does not match the front buckets. What's up?
  • Theflyersfan The two Louisville truck plants are still operating, but not sure for how much longer. I have a couple of friends who work at a manufacturing company in town that makes cooling systems for the trucks built here. And they are on pins and needles wondering if or when they get the call to not go back to work because there are no trucks being made. That's what drives me up the wall with these strikes. The auto workers still get a minimum amount of pay even while striking, but the massive support staff that builds components, staffs temp workers, runs the logistics, etc, ends up with nothing except the bare hope that the state's crippled unemployment system can help them keep afloat. In a city where shipping (UPS central hub and they almost went on strike on August 1) and heavy manufacturing (GE Appliance Park and the Ford plants) keeps tens of thousands of people employed, plus the support companies, any prolonged shutdown is a total disaster for the city as well. UAW members - you're not getting a 38% raise right away. That just doesn't happen. Start a little lower and end this. And then you can fight the good fight against the corner office staff who make millions for being in meetings all day.
  • Dusterdude The "fire them all" is looking a little less unreasonable the longer the union sticks to the totally ridiculous demands ( or maybe the members should fire theit leadership ! )