Whenever a drive-shaft or half-shaft is removed from a vehicle, the FSM always tells you to mark it so that it can be reinstalled in the original orientation (with respect to the pinion).

Why?

These components should all be independently balanced right? So what is the purpose of preserving their orientation?

Just curious,

 

But why do they need to be put back the same way they came out? If the DS/HS are balanced correctly, it shouldn’t matter which way they are installed, right?

 

Because the shaft itself is balanced, and there may be balance weights on the bolts. The whole assembly must remain balanced to be vibration free.

 

So when Mazda put my car together, did they balance the shafts while they were connected to the pinion/flanges?

I want to replace one of my half shafts with one I have from another car. Is this “balancing” going to be an issue?

 

No. If you should encounter any vibrations when after changing driveshafts, half shafts, just remove it and turn them 90 degrees and give it a try.

 

I have swapped driveshafts on my TII and just put it in whatever way it would fit... I had no issues!

 

When I dropped my driveshaft I did not notice any balance weights on it. I just had lock washers. However, there was a piece of metal stamped on the drive shaft about six inchs forward. Maybe the size of to postage stamps.

James

 

The shaft itself is balenced via metal plates ranging in size and location on the shaft itself. No worries, pop it back in whatever way you get it out.

 

When I removed the driveshaft from my RX-7, I sprayed a small dot of yellow spray-paint on the mounting flange to ensure that it was installed in the correct place.

 

haha, thanks ed... heh, i hope it doesnt make much of a difference, i just disconnected both halfshafts to remove the hubs w/o marking htem...

 

I took mine off to change the clutch and when I put it back on I had a lot of vibration, took it off and turned it, there was a little vibration but not as much. Now I can't get rid of the vibration. I would mark it just to be safe.

 

Is there any way to tell what the correct way for them to go back in is?

 

not really just mark it or try to remember how it was on there before you took it off. Like look at the weight(plate on the driveshaft) is and put it on that way.

I think that when I put mine on different it threw the whole thing off. Now I have to go get it rebalenced.

 

i had a driveshaft go bad and replaced with another. car ran as smooth as i could have asked for. i never bothered to ask if it was installed more than once (turned) due to vibration, though.

 

I'm not sure exactly what happened with mine.....

 

Yeah I forgot to mark mine, and since both axel halves are the same in a non-lsd differential I may have swapped which side they go on as well

Let's see that's 32 different combinations to get back like it should be. Lets I hope I don't get any vibration issues.

I did remember to mark the driveshaft though If you didn't, that would be 64 different combinations - ouch.

 

Ok, since we are on the topic of marking stuff.

If you remove your rear hub the Haynes man recomeds you mark the relationship of the hub splines to the half shaft splines. Why?

James