Drive Line Vibrations Explained

I have read a lot of threads on this board about drive line vibration problems. A friend showed me this video on YouTube that explains it in very simple terms. It's not a solution but knowledge does lead to understanding.

AL

https://www.youtube.com/watch?v=gmV4qwLfOMY

 

Wow, I had no idea how that worked. Thank you very much! After my lift I started experiencing some vibes on start off. Reducing my rear lift some helped a lot.

 

Good info for those who don't understand why the drive line vibrate the way it does.... including Toyota and their engineers It only took a 3rd gen Tacoma to hopefully fix the issue LOL.

 

also alot of the driveline vibration on our 2nd gens is due to the weak center carrier bearing allowing oscillation of the center joint.

 

Very nice illustration.

Someone please explain to me though, in the video, the input end is always at a constant velocity no matter the operating angle. The oscillation or vibration is at the output end. On our truck that has vibration issue, it's felt toward the front of the truck, but that's where it is equivalent to the input end in the video example, no? Is the vibration just traveling all the way from the back of the truck to the front?

 

Great post!

Thanks

 

neato!

 

yes.

And a majority of the vibration is from the center carrier bearing support... which is directly behind the cab / under the back of the cab.

 

When I was a young guy was told to always mark yokes and drive shaft as shown in this video when changing universal joints to avoid vibration/balance issues.

This helps me understand the other dynamics involved in driveline vibration issues.

Thank you for posting this.

 

Great video. I learned something tonight. Thanks!

 

In his video, there is zero load on anything. Newtonian physics still applies, action and opposite reaction. If you put a wheel on that rear shaft of his, and put it on the road, now you are trying to vary the speed of that tire, which means the truck is having to speed up / slow down to match the speed of the wheel that is changing. Part of this force speeds up and slows down the truck, the other part of the force is applied to the transmission which causes the engine to rock back and forth and produce the vibrations up front that you feel.

In his demo, the spinning shaft is free to change its speed on the output end. But when you couple that to the ground you get driveline shuddering since now resistance on one end applies a force on the opposite end...

 

Great Video!