Drive shaft out of phase

I've attached an annotated copy of the DS picture pointing out the match marks.

After calling all the other shops in the area (San Diego/El Cajon)- the owner of the first shop is just known to be that way, but apparently does incredible work. Apparently, he is old, overworked, and wants to retire, but can't. Not that I think that's a good way to run a business. There is another shop I can try, it's just a bit further away than I feel comfortable driving to on the front driveshaft alone.

 

That flange right after the carrier bearing is oriented properly? Can't you just remove the nut on the flange and rotate the flange 90*?

 

I can't remember if the flange between the cardan and CB is a square pattern or rectangle pattern. If it's square then yeah it's easy to put it back 90deg out of phase. Rectangle you wouldn't be able to put it back together wrong. The flange that is pressed onto the splines holding the CB on is a very different story, there are many possible angles, but as long as your yokes look more or less lined up it should be fine.

 

The rest of the marks would not align if I rotated the flange after the carrier bearing.

 

Isn't that the point? It's wrong and needs to be changed?

 

Ya take off the staked nut and rotate that flange or just rotate the shaft itself 90 deg if that's a square bolt pattern, I can't remember. 90 deg out of phase is definitely wrong, even the FSM says so, and reference the video I posted above for why.

 

The only indication that it is wrong, is once you take phase into consideration. The vibration was almost certainly a result of putting new springs on. The drive shaft is balanced otherwise.

 

but balance is a moot point if it's out of phase.

Put it in phase before you troubleshoot balance.

 

2nd that...balance and phase are two very different things. Phasing has to do with maintaining a constant output angular velocity (see the video I posted). Balance has to do with the the moment of inertia/C.O.G of the driveshaft itself.

 

And yes to answer that, you can get a vibration after lifting the rear because your driveline angles (pinion angle) change which in turn affect the phasing of the driveshaft. So it's possible that if you lifted it this vibration became noticeable because the phasing was now off by a few more degrees. The correction for this is either axle shims to fix the driveline angle or adjust the driveshaft phasing by a few degrees.

 

Again, I just struggle with the idea of intentionally changing the phase if this is the way it always has been and was balanced from the factory in this orientation. I understand that it might be wrong, but it seems like making a change to the phasing would be a breaking change to the current balance.

I obviously need to find a shop that willing to hear the whole story here, and willing to work on it knowing that I intentionally altered the phasing from the original setup. Like I don't want them to see non-aligned match marks and question whether the rest of the work was performed correctly.

I just don't want to make it so bad that the shop tells me the drive shaft is garbage after I just spent money on new parts for this drive shaft.

I didn't intentionally try to add more lift, I just think that I ended up with additional height compared to the 20 year old stock packs. But I was hoping that I could add a washer or two to the carrier bearing. I didn't take before and after measurements with the new spring packs, but it couldn't have been much height.

 

I would think a good driveshaft shop won't even balance it if it's out of phase. Especially 90 degrees out of phase. Try just showing up and walking into the shop to talk instead of trying to explain it over the phone.

 

even a perfectly balanced shaft out of phase will vibrate once it's at an angle. Stock you did not have much if any angle so you did not notice. Now you are lifted and it's at an angle.

You need to fix the phase before you worry about vibrations.

You are placing too much priority on balance and not nearly enough on the importance to phase.

 

I'd bet they split it at the flange and balanced it in sections.


not to mention they balance perfectly straight.

 

It's been lifted for nearly 20 years without a vibration issue until I replaced the springs - 1.5" AAL + 1.5" shackle.

Edit: I replaced the top three springs, and kept the existing AAL and shackle. The AAL and shackles were replaced around 2014 along with the rear shocks.

 

I think that's a better plan than to scare the shit outta them with the backstory over the phone. and even better if they prefer it split already, then I won't even bring the phasing into question...

 

NJ

 

Dad, I believe I made the same mistake when I changed my Trans seal, new carrier bearing, and a new ujoint...My buddy , who is usually a brilliant mechanic, must have been a little high when he marked my stuff for me...So, I have a vibration problem now...But I'm gonna drop it off at Knoxville Driveline today or tomorrow..This shop is widely considered one of the best in the nation..Their website proves how professional and damn nice they are...I went by and visited them to ask questions awhile back..The owner and me actually talked 2 hours...Hes well aware of the Tacoma problems and their lack of giving a damn...This is the price he charges...Its 80 bucks for a diagnostic...If it needs turned or rebalanced, they do it and remark it for you...And its STILL only 80 bucks...The only time the price changes if is they add new parts...I have read a bunch of bad stories here about the lack of a good shop...These guys will take your calls and work with you even if you are calling from California...

 

Follow up - I was able to work on the drive shaft last weekend. I installed it with the correct phasing. This did not change the vibration. I removed it, put it back in as it was (out of phase) and the vibration was the same. So I pulled it again, put it back in phase, and reinstalled it. I added three washers to lower the carrier bearing, and that did reduce the vibration. So I guess I need to measure my drive line angles and likely correct them with a shim. It's just interesting that during the 20 years this truck has been lifted, it's never been an issue until I put new springs in.

 

Remove the the splined slip yoke and dig out any dried old grease inside the splined tube. That happened to me and it fixed my issue. That slip yoke only get 2-3 pumps of grease. That's all.