apc

If you removed a rear drive shaft without first marking both flanges, how do you determine if it is correctly matched to both flanges?

I had a shop replace my u-joints, and now the rear has a slight shake to it. There is absolutely no markings on the flanges to indicate it was mated back properly.

Thanks in advance.

eric-the-red

There are only 4 positions, or maybe 2 if the flanges aren't square. I can't remember right now. You just have to try them all until the shaking stops.

foxtrapper

The problem isn't bolting the two flanges together. That's not balanced. The problem is how they put the two yokes together that suround the u-joint itself. That is balanced, and can result in shaking when reversed on assembly.

eric-the-red

Missed the part about the U-joint getting replaced, now I get it. :pat:
I guess take it back and get them to fix it.

OtFoFyRoOtAaD91

apc

Thanks OtFoFyRoOtAaD91 for the pic.

Is that for a Toyota?

george16

Get a flashlight and see the mark where it originally on. You'll notice it because it's "cleaner" than the rest of the pinion flange. I had to do this on mine because I forgot to mark it during the locker install. The drive shaft has a distinct shape and you'll see it when you shine your flashlight on the pinion flange. The driveshaft is a balanced unit and you'll get vibrations if not installed properly. I found it out the hard way.

George

Shane

Oh jeeze, guys, it doesn't matter what position the flanges are in! Don't worry about that.

It's the yokes at either end of the shaft that have to be lined up. In the picture above you can see they're like this:

=}------{=

which is correct, you don't want them like this:

=}------=}

The only way these can get screwed up is if you pull the slip joint apart and don't reinsert it properly.


DON'T WORRY ABOUT THE FLANGES! Look at the yokes at the ends of the shaft, are they lined up to each other? If not unbolt the shaft and try splitting the slip joint apart and reinserting it so that the yokes match up, if you can't get it right on try spinning one half around 180°. The other possibility is they didn't get one of the joints centered, get the wheels off the ground and spin the shaft to see if it has any runout.