2017 GMC Sierra 6.2 8 Speed Limiter at 84MPH?????

[Tanner Smith]

yeah I checked to see if in teen driver mode and it said off. Maybe in valet mode? I called the dealer and they said that the ecm may need to be reflashed, I plan on supercharging it, so my tuner guy could reflash it for me instead and fix the limiter I'm sure. 

[James Dink]

21 hours ago, rav3 said:

I don't understand your post. What's up the driveshaft?

 

long truck driveshafts have speed ratings 

[rav3]

3 minutes ago, James ****** said:

 

long truck driveshafts have speed ratings 

WOW! I wasn't aware of that. I would of thought that the drive shaft was designed to be at least 1.5 to 2x of what the max speed of the truck was, not the other way around. What's the limit on these trucks? I have not read of any driveshaft issues other than maybe the vibration  coming from the Universal joints. BMW's doesn't mfg their DS to be serviceable (replaceable U joints) because of their precision balance. Makes me wonder how well balanced the GM's shafts are.

[CamGTP]

You haven't been around the performance aspect of these trucks much then. There are many threads on various forums and even here about exploding driveshafts. Even youtube video's of them going boom on the dyno. This isn't exactly the I'm going to turbo and supercharge my truck forum with build threads and all that.

 

Anything over 100 mph is just asking for problems in my eyes. Especially the aluminum driveshafts on the later GMT-800 and all GMT-900's, they like to grenade.