Lets Play a Game: Driveshaft or Fine China?

"shpuker" (shpuker) 07/13/2016 at 11:46 • Filed to: None

1

23

I’ve been searching around for a while the last 24 hours trying to find more potential issues with the 2015/2016 GM 5.3L V8 driveshafts after mine !!!error: Indecipherable SUB-paragraph formatting!!! on my way to work... In the wet... Here’s what I’ve found so far.

First and foremost, it appears that this specific driveshaft appears in all 2015/2016 GMC Sierras, GMC Yukons, Chevy Silverados, and Chevy Tahoes. If I had to guess I’d say it also appears in Cadillac Escalades and Suburbans also have the same driveshafts, or similar. I haven’t gotten a chance to look into this however.

Second, I’m not the first one to suffer a failure of this driveshaft. The one in the video above is a bit more ridiculous looking, but in all reality would’ve occurred from a similar incident. Really the main contributor to this thing going full pretzel vs mine shearing off is the position of the failure. This one occurred a few inches further down the shaft, and thus slightly further from the cardboard insert, which would provide slightly more support.

Then there’s the truck I used in the lead image, obviously an older generation so it uses a different driveshaft, however it’s still worth mentioning due to the !!!error: Indecipherable SUB-paragraph formatting!!! .

Getting into potential reasons for why mine failed so early on in the vehicles life, I’d have to assume there was some sort of imperfection in the shaft or that somehow it was damaged in some way. Other than that though, maybe it comes down to GM producing a driveshaft that likely is just too fine on its specifications to put up with the cyclic loading you get from a truck? That’s painful for me to accept though because my truck is about as light as you can get one, being a 2wd regular cab worktruck...

This isn’t the first time GM has gotten heat for driveshafts though, even Top Gear had issues with them in their rescue Hammond special.

Update : Filed a formal complaint with the NHTSA and sent an inquiry to GMC requesting some form of correspondence in regards to the failure. Both were very recent so no response from either yet, though the report is already live on the NHTSA website.

http://www-odi.nhtsa.dot.gov/owners/SearchR…

MontegoMan562 is a Capri RS Owner > shpuker 07/13/2016 at 11:50

0

WOW holy shit that’s bad.

BringBackTheCommodore > shpuker 07/13/2016 at 11:58

0

Might I recommend:

http://www.fourwheeler.com/project-vehicl…

It’s on a Titan but the driveshaft “fuses” can be set up on pretty much anything with a driveshaft, and you can keep spare sets of “fuses” just in case.

shpuker > BringBackTheCommodore 07/13/2016 at 12:08

1

Something tells me they don’t make a model built from porcelain, nor the mental stability of Charlie Sheen...

Tekamul > shpuker 07/13/2016 at 12:11

1

Driveshaft?

Oh. Driveshaft

Yeah. I think GM f-d up on this one. That full twist off is ridiculous. I wonder if there was a supplier change for 2015?

Highlander-Datsuns are Forever > shpuker 07/13/2016 at 12:11

1

That’s heartening to know when I’m towing 13,900 lbs in our 2500 HD.

HammerheadFistpunch > shpuker 07/13/2016 at 12:13

1

I see a general problem with this thin wall hallow core concept (not that im a driveshaft expert or anything) in that it wouldn’t take much local damage to severely compromise the entire shaft by creating a stress concentration point. I get that hallow is light and all, but when you are talking about something that transmits a lot of torque, and is highly susceptible to stress concentrations by the fact that it twists....how can you get away with such fine tolerances in the real world?

Wacko > shpuker 07/13/2016 at 12:15

4

man if only GM used high strength steel in their driveshafts instead of truck beds.

shpuker > Tekamul 07/13/2016 at 12:19

0

Too perfect.

I’m not sure though. If so I doubt GM would want to talk about it much. I sent a general inquiry to them though so we’ll see what happens.

Smallbear wants a modern Syclone, local Maple Leafs spammer > shpuker 07/13/2016 at 12:20

2

Never been so glad to see rust when I looked under my truck.

Don’t put another OEM one back in. Pretty sure you can get one aftermarket.

shpuker > HammerheadFistpunch 07/13/2016 at 12:24

0

My thoughts exactly. I did a little number crunching to see what it SHOULD be able to handle and that suggested a FOS of around 15 which is massive. However any sort of damage or material imperfection on that thin of a sidewall would severely compromise that number. Even something as simple as putting a torsional force on it as the same time as the torque could cause this sort of failure, let alone the long term impact of cyclic loading on an aluminum part.

shpuker > Smallbear wants a modern Syclone, local Maple Leafs spammer 07/13/2016 at 12:25

1

I’m going to let GM replace this one (I swear if they try to pull some bullshit), but you can bet my first upgrade is going to be a new driveshaft and some decent u-joints.

gmporschenut also a fan of hondas > HammerheadFistpunch 07/13/2016 at 12:34

0

Because the extra mass in the center does little to increase overall rigidity. Thus increasing diameter (and reducing thickness) to reduce weight.

Now resistance to deformation that’s another arguement.

I would say given the typical application of most pickups it is not as highly ranked as improved fuel economy.

HammerheadFistpunch > shpuker 07/13/2016 at 12:34

1

It reminds me of my bicycle sales days, when the lightest aluminum bikes would fail because there was a small dent in the tube cause by a single fall. When the entire component is stressed, pretty important to make sure that component is shielded from damage/strong enough to handle a stress point/built with “firewalls” to prevent catastrophic damage.

Smallbear wants a modern Syclone, local Maple Leafs spammer > shpuker 07/13/2016 at 12:38

0

Here’s a question for you: Do you find the driveline is “slack” on the new trucks? I.e. can you feel a clunk when you pick up from coasting or accelerating of low-speed residential area corner?

HammerheadFistpunch > gmporschenut also a fan of hondas 07/13/2016 at 12:40

0

yeah I get the engineering side of it, but at the end of the day, stones are going to ding that sucker up and it needs to have better failsafes to prevent a total failure like that.

shpuker > Smallbear wants a modern Syclone, local Maple Leafs spammer 07/13/2016 at 12:59

1

Certainly, yes. There’s a very obvious amount of play in the drivetrain. That could also have been a factor here.

Smallbear wants a modern Syclone, local Maple Leafs spammer > shpuker 07/13/2016 at 13:01

0

Good. Mine must be normal though.

Still hate it, no matter how much I like the truck as a whole. There must be SOMETHING that can be done about it...

shpuker > Smallbear wants a modern Syclone, local Maple Leafs spammer 07/13/2016 at 13:03

1

I mean the 2 piece from the V6's is probably more durable. Custom ones are typically cheaper than the stock option and much stronger as well.

gawdzillla > shpuker 07/13/2016 at 13:19

1

oh damn, didnt see your earlier post

i got a 2015, let me find some wet road and beat on the truck real quick

Urambo Tauro > shpuker 11/07/2017 at 22:45

0

(Old post, I know.) So what ever became of this?

shpuker > Urambo Tauro 11/08/2017 at 09:51

0

Turns out the dealer had missed a small piece of drywall that was wedged between the cab and bed during their inspection before selling me the truck. That piece of drywall put a small groove into the driveshaft which caused it to fracture cleanly along that line. Dealer fixed it and covered all costs.

Edit: AKA Technically it’s not an issue with the driveshafts in general, but god help you if you damage one in any way. Dealer ended up being really cool about everything once they realized it was something they should’ve fixed in the first place.

Urambo Tauro > shpuker 11/08/2017 at 10:09

0

GOOD.

I still hate the design of that driveshaft, though. Lemme guess- they just gave you another one exactly like it, didn’t they?

shpuker > Urambo Tauro 11/08/2017 at 10:58

1

Yea they didn’t have much of a choice though. I’m pretty sure they claimed it as a warranty item. If I ever go to do any power modes/put in a LSD though the driveshaft is the first thing that’s getting swapped.