What's up guys. I have a 12 denali 2wd with drop shackles the stock blocks removed and 411s. It has a one peice aluminum drive shaft and factory wheels. My problem is around 85 I get a nasty vibration. I think the stock shaft is not happy with the gears and that speed. Has anyone swapped to a 2 peice one yet? If so what one did you use. Thanks

 

you need to check pinion angle, this is typical of most lifted or lowered vehicles. having a 2 piece wont fix issue if you have driveline angles off

 

I read the one peice shafts should have differant angle like if the pinion is down 3 degrees the tail shaft should be up 3 degrees to cancel out and that's how mine is now. I never had the vibration till the gears got put in. That's why I think the drive shaft to long for the rpm its spinning. Or it needs a 2 peice with a carrier to keep it from vibrating. I also read about high speed balancing the stock one also

 

https://www.performancetrucks.net/fo...-535901/page2/

 

This web site is great

 

Here you go!

 

The gears could just be pointing out the pinion angle problem... its spinning the driveshaft a lot faster. You have a longer 6th gear than my 4th and I didnt have any problems with my stock driveshaft.

Double check your pinion angles and if need be have the stock shaft balanced. You shouldnt need to go to a 2 piece just yet. If you were makign more power or going a lot faster than that on the reg than I would suggest it.

 

Alright I will get an exact angle for peice of mind just to know. I'm going to do a 2 peice still. I have a 447 cubic inch world lsx motor sitting at the house that's going in it when I decide what I want to do with the truck. Thanks for the info

 

I just installed 4.10's in my 2009 crew cab. Same vibration about 80-85 but seems to go away after 90. My suspension is completely stock. I had the driveshaft balanced today and they took some of the factory weights off. I'm about to put it back in now. Feel free to text me. 940-231-5151
Patrick

 

Well, still vibrates.