Carbon Fiber Driveshaft EXPLODED!!

[acammer]

Originally Posted by dma05

UPDATE!
It’s been some time now since my DSS exploded and I finally bought a new Gulf Coast carbon fiber one to put on the car. I installed it this weekend and uninstalled the DSS one. It looks like the DSS failed right by the coupler. It was so twisted that I couldn’t take the bolts out!! Definitely a weak point. I’m done with DSS.

The new Gulf Coast is installed and working great! I also decided to wrap the X Pipe exhaust so that heat won’t be an issue.

I wanted to make sure to give an update on this post.

Seeing that, I'm pretty sure your failure was those coupler bolts backed out enough to introduce some vibration, and once that started it progressed rapidly to a catastrophic failure. My G-Force axles use a similar design to couple the axle bar to the CV joint, and I had them back out on me despite generous use of loctite. They were living under my stick shift car doing aggressive things on sticky tires for several seasons, and I never checked them like you really should when you do that kind of stuff - so it's 100% my responsibility in that case.

On a driveshaft I wouldn't think they would loosen up, but there are all sorts of reasons that they still could have. Sorry to see it happen. Sounds like a good experience with Gulf Coast, I keep hearing good things. I'm very curious about a carbon fiber shaft for my own car, as I run up to the critical speed very quickly with such deep gears, and carbon would extend that critical speed up a few thousand rpm. Maybe someday!

[dma05]

Originally Posted by acammer

Seeing that, I'm pretty sure your failure was those coupler bolts backed out enough to introduce some vibration, and once that started it progressed rapidly to a catastrophic failure. My G-Force axles use a similar design to couple the axle bar to the CV joint, and I had them back out on me despite generous use of loctite. They were living under my stick shift car doing aggressive things on sticky tires for several seasons, and I never checked them like you really should when you do that kind of stuff - so it's 100% my responsibility in that case.

On a driveshaft I wouldn't think they would loosen up, but there are all sorts of reasons that they still could have. Sorry to see it happen. Sounds like a good experience with Gulf Coast, I keep hearing good things. I'm very curious about a carbon fiber shaft for my own car, as I run up to the critical speed very quickly with such deep gears, and carbon would extend that critical speed up a few thousand rpm. Maybe someday!

The coupler bolts actually didn’t back out at all. That was me taking an impact trying to force them out since I didn’t think I could get to the 3 main bolts underneath the coupler. Once I realized they weren’t going to back out through the twisted mess, I figured out how to get the main 3 bolts out instead. The bolts on the DSS had red loctite and were tight.

[acammer]

Originally Posted by dma05

The coupler bolts actually didn’t back out at all. That was me taking an impact trying to force them out since I didn’t think I could get to the 3 main bolts underneath the coupler. Once I realized they weren’t going to back out through the twisted mess, I figured out how to get the main 3 bolts out instead. The bolts on the DSS had red loctite and were tight.

Ok - that makes much more sense, like I had said it would seem unlikely - but looking at the picture made me believe they had been the source of trouble. I don't know enough about CF driveshaft design to really have any meaningful input here! Keep us updated on your long-term experience with the Gulf Coast piece.

[olblue75]

My DSS shaft fwd bolt backed on the drive home from a track day at NCM I’m sure they were getting loose during my runs. Ordered a new shaft drilled lock wire holes in the bolts and used safety cable along with lock tight so my bolt should not move at least for awhile.