Drivetrain Vibration Due to Loose Companion Flange

[mikedks]

So I got my 95 4Runner project going awhile ago but just haven't had time to work out the kinks. Everything works well, but it drives like crap, mostly due to the need for new properly balanced front tires. However, the drive train has a wicked vibration around 45-55 mph. I assumed, guessed, hoped that it was the rear U-joints. Pulled the rear shaft with every intention of replacing, only to discover the rear joints were in good shape with no play. So I shined the light on the differential, no visible issues, then took a look at the companion flange coming off of the transfer case, checked the bolt, and wouldn't you know it was loose!. Weird, cause the bolt is still staked(properly I may add) but you could definitely move the bolt by hand. I unstaked it, cleaned the threads, applied some loctite, and guesstimated the 90 ft/lbs of torque, then restaked it.
Will put the shaft back on this weekend and see if that cures the vibration.

Was just wondering if anyone has experienced anything like this, its a first for me.

 

[fourwd1]

Yes, I had the same thing happen once.
Thought it was a u-joint too.
Retorqued it and never had a problem since.

 

[mikedks]

Yeah, same here. Just finished my test train and the vibration is gone. Only thing I need to diagnose is a slight burning rubber/burnt gear oil or grease smell
coming from the passenger rear tire area after a drive. Really need to put your nose into the tire to smell, but it's there.

At this point the 4Runner is almost drivable, just need to get some new BFG's up front,install the manual hubs, and maybe a steering damper and I'm on my way!