Drive Shaft Vibrations Solved Step-by-Step

I finished out a leaf upgrade on my truck at the end of last season using a set of the Dakar EL095R packs. While doing this upgrade I did install the Old Man Emu carrier bearing drop kit. After letting everything settle out I still am getting some take-off vibrations as well as vibrations around 70 mph on the highway. It is nothing major as I have been driving with it for a few months now however I'd like to correct things if possible. I have taken the measurements as directed and they are shown below.

First half of driveshaft: 5.7 degrees
Second half of driveshaft: 5.3 degrees
Rear-axle housing: 2.7 degrees

Should I look into getting an axle shim first or simply play with the carrier bearing drop as my axle angle is already under the 3-degree point?

 

What kind of vibrations are you guys experiencing? I have terrible vibes after installing a 1” block. At 1-28 mph it feels like driving over rumble strips. It’s more noticeable when slowing down than starting off. Then at 40-55 mph I get barely noticeable pulsating vibes. Nothing changes when put in 4hi so I don’t think it’s needle bearing related.

 

Sounds like a needle bearing issue. Replace the needle bearing with a ECGS bearing and it will eliminate the front end vibes. Whenever you lift the truck in front you will get some vibes because the needle bearing is not made for lifted tacomas. If you put it in 4 wheel drive and the vibes go away it is usually the needle bearing. The Drive line vibes that this thread is talking about is when you lift the rear and your drive shaft angles are thrown off which can be corrected with a carrier bearing drop and possibly shims.

 

That’s the thing though. It doesn’t go away in 4hi. Pretty much everyone who’s had a carrier bearing problems says the vibration goes away in 4hi.

 

Sorry, I misread your post. So your 1 inch blocks are in the rear correct? What type of taco do you have? Single cab? DCSB? DCLB? This can make a difference in the length of the driveshaft and the possible angle issues.

 

Correct, 1” blocks in the rear. DCSB. I took a quick look yesterday and I can tell the carrier bearing is significantly off center. I’m not even sure there will be enough play to get it centered. I know from my alignment that my thrust angle is .21 degrees if that helps anything. Also, I really appreciate the help here on TW!

 

Well it needs to be centered, so start there. Run a string line and see what you’re working with.

 

So do you have a carrier bearing drop as of right now?

 

No, I haven’t changed anything other than 2” lift in front. 1” block in the rear with no shims. I’ve ordered the angle gauge so I can check the driveline angles.

 

I would try the CB drop....it is a very small price to pay to correcting the angle you might need to correct.

 

So, I've got a '15 DC SB. On stock suspension I had a take off shutter, it was worse the harder I took off. I took it in and had the dealer check it out (still under warranty). Tech replaced the needle bearing and CB bearing. New vibration showed up at 25-35 MPH. They replaced the shaft assembly. All seemed fine after the shaft assembly was replaced.
Installed RXT leaf pack on stage 2. No shims or CB drop. Take off shutter is back and worse than ever. I have a small vibration at 45 mph or so. It shakes the passenger seat up to about 15 mph.
I used some square Unistrut washers and cut a notch in them so I can slide them in. Takes care of the 45 mph vib.
I got the HF angle finder and measure the TC flange, set to zero and measure the pinion flange. 4.8 degrees. If I pull the bottom of the bar I'm using toward the front of the truck the angle increases.
Seems to me the pinion angle is pointed up toward the truck in relation to the TC. Can this be correct? Do I really need to push the pinion angle down 4 degrees with the shims? Actually install it backwards to push the pinion flange down?

I'm not sure I had the weight of the vehicle on the rear when I tightened everything up so I'm going to loosen everything and try that this afternoon.
I'll have my laser this afternoon to check X axis on the CB as well. The new UJ's don't have zerks for a string line.

 

I just bought a 15 TRD sport 4x4 access cab. truck has 60k on it. It has a very very slight shudder, vibration, jiggle(if that makes sense) on take off. Truck is CPO so I have a bumper to bumper warranty right now but from what I have read it seems like sometimes the dealer makes it worse. My truck has a production date of 5/15 so it has all the updated leafs. After the jingle on initial take off the truck is smooth as silk. Sometimes I feel a tiny vibration from 1st to 2nd shift(auto) but I have to really be paying attention to notice it. It drives so good after take off I almost don't want to mess with it and end up with vibrations at a higher speed.

 

Measurements below. I've been able to stop most of the vibs except the take off vibs. If I understand this thread at all, and with these measurements, I may just order a TW driveshaft. My pinion angle is pretty much pointing to my TC as it sits and that is what the TW web site says for the DC driveshaft.

Thoughts?

Tcase versus rear pinion angle (zero on front flange, measure rear pinion flange)
___5.2__degrees (photos #1 thru #4)

Tcase operating angle (zero on front flange, measure first shaft)
__3.6___degrees (photos #1, #2, and #6)


CB operating angle (zero on front flange, measure first shaft - second shaft)
_3.6____degrees first shaft - __7.0___degrees second shaft = __3.4___degrees (photos #6 & #5)

Pinion operating angle (zero on pinion flange, measure second shaft)
___5.3__degrees (photos #1, #2, and #5)

Is the pinion off pointing up or down?
___x__up ______down (photo #4, keep your thumb pressed against the rear flange and with your other hand pull the bottom of your metal measuring bar toward the front of the truck. Watch the angle change: if the number increases, you’re pointing UP, if it decreases, you’re pointing DOWN. If you didn’t get a magnetic angle gauge, you need more hands).

 

I upgraded my leaf pack from the MD Dakars to the HD Dakars. I have the OME CB drop but no shims. I cannot for the life of me tell if I am feeling vibes or if its in my head / uneven road / tire tread. Around 62 MPH I THINK I sometimes feel a slight vibration, but other times at the same speed I don't. Putting the truck in neutral does nothing to make the "vibes" disappear. Coasting, accelerating, decelerating all make no difference in what I somethings think I feel are the vibes. I just think I am overthinking things too much and looking for a problem where there isn't one because all I read about are people chasing down vibes after a lift.

For those that have had vibes, are the vibes obvious? Or do you have to do like I'm doing to convince yourself that there ARE vibes.

For reference, my three measured angels are:
3.8
5.3
4.2

 

I have a bone stock 2015 AC. I get the same thing on the highway. Sometimes it feels like there is a shake/ vibration and sometimes its smooth as glass. I thought maybe I was being over sensitive.

I do have a take off shake/ shudder/ vibration on take off. Very minor though.

 

Are you running the Deaver leaf pack J66? I am thinking about doing that instead of adding a leaf or doing the medium duty OME leaf kit. Everything else on the truck will be OME...884's and nitrochargers front and rear. I was thinking the Deaver leaf pack would be a better option and smoother ride but based on this thread...sounds like the driveline angles are going to be a headache.

Thank you for any answers. Trying to figure out what to do for a lift :X

 

Trying to get to the bottom of this.. ideally without reading 47 pages! I have read the first few and have to say I am still unclear as to what I need to do... Does the diff pinion flange want to be pointing up from the transfer case flange? Or down... Zeroed out on T case flange I am 2* up which in my mind mean I need to get 2* shims. If someone can simply clarify that would be awesome.

I hpe my image appears.. not used to this Media gallery thing.

 

I know I can do a carrier drop to even out that 1.6 and 10...or at least i hope so..

 

There are four different ways to set-up a 2-piece driveshaft.
Three of them require having zero angle on one of the u-joints and equal angles on the remaining u joints.

The fourth requires all angles add up to zero. Downward angles are positive; upward angles are negative. Example(2)+(2)+(-4)=0

You're the fourth...
(1.6)+(8.4)+(-10)=0

However, I see you have a '99. If it has a double cardan u-joint, it requires something else. The double cardan is self canceling; the other two u-joints must be equal.

 

I have similar questions and will post my numbers later today, but based on what I’ve read I’d start with the carrier bearing. you have an 8.4 angle. Get that to 1 or less (good) and measure again. The tc angle will be more down and you’re pinion angle will be less up, and they’ll be closer together (good)

here’s what I can’t reconcile. I read that the carrier should be less than 1, and the tc / pinions should be less than 3, BUT the pinion and transfer case should be parallel each other. I have 4 down out of the TC and 4.7 up out of the pinion with the pinion 1 up. If I drop the carrier I’ll be +4 down (bad) and -4 down (good) at the pinion. Shimming the pinion will lower all my angles (good) but I’ll have less of a parallel line from the tc and pinion (bad).

it also sounds like a lot of trial and error, so as you make an adjustment or 2, you may want to drive / test / assess. Or go TW one piece and forget the carrier ...