Trying to diagnose a pulsing driveline vibration

Sorry to Hi-jack a thread, but instead of me making one, I figured I'd post here since I'm basically having the EXACT same problem. Mine occurs at slightly different speeds.

I've got a 2001 3.4L Doublecab w/ auto tranny w/ 141k miles. I fee absolutely NO vibration until I reach roughly 60-65 MPH. After that, I seem to get more of a pulsation vibration than just a vibration. One thing I will mention is that I didn't have this vibration before my recent frame replacement, but I'm not sure that has anything to do with it.

I've checked all the U-joints (tried to shake the hell out of them) but none of them seem to move at all. I checked all of the oil in the diff's and transfer case just to be sure. Everything seemed good there. Also jacked up the front end, tire by tire to check wheel bearings and didn't feel any play there. The front CV joints are new ones from Oreilly (originals had torn cv boots).

Now I did replace the center bearing (carrier bearing) with one from Oreilly Auto HB-26, but after reading the carrier replacement thread, there are a few things that I didn't do that maybe I need too. I was in a hurry so I didn't make the alignment of where the shafts came off at. I know that the shaft to the rear end and the shaft to the transfer case are either right on or 180 out because of how the dirt was. but at the same time, I do know for a fact that the carrier bearing section is 90* off in one direction or the other.

The other part that I noticed I didn't do was torque part on the nut that holds the carrier bearing on. I didn't torque mine, then back it off and retorque it. I just torqued it up and left it. Think it could be to much torque? I will pull the whole thing off, and try and get it lined up and torque it right this time.

But, even with the things that I did wrong on the carrier replacement, my vibration is still in the same spot and acting like before. Around 65mph it's just a pulsation. Almost the same to that if you are driving on the drunk bumps on the edge of the road. You get that WOMP WOMP WOMP WOMP WOMP sound. One that that I did notice was that it seem more pronounced that if you are going around a left hand curve at 65-70mph. Seems like it's worse. Almost makes me wanna think that something is off in the front end. I didn't feel anything and when the frame was replaced and the front end alignment done (which i'm assuming they done) they didn't say anything about tie rods or anything being bad.

I'm going to play with it some more tomorrow, but If i can't find anything, it's headed to the shop on Monday. Gotta get it fixed before the drive to North Dakota.

So other than the carrier bearing, what would everyone else check that I haven't listed in this post.

Again, sorry for the Hi-jack.

 

Ive been reading up on the vibration dampener on my truck (after bouncing mine on a rock: see thread: http://www.tacomaworld.com/forum/1st-gen-tacomas/307710-banged-something-rock-what.html)


Check to see if you have a driveline vibration dampener as well. If not, might want to get one (ONLY FOR AUTOMATICS).

 

You could have a bad tire (bulge, partial tread separation). You could check each tire, one at a time, by jacking up each corner. Spin it if you can.

 

Check on the vibration dampener. Seen it under there when I was taking everything apart.

 

Your tires will do that,,from sitting in one spot and getting cold soaked. Then you take off and the flat spot is slapping the ground until they warm up a bit and stretch back to round.

 

I took a look under mine real quick and noticed the weights on the 2 drive shafts are about 90* off from each other. I will pull both drive lines off tomorrow and get the weights lined up. Maybe with the weights being offset it's causing the high speed vibration. If that doesn't do it I'm just going to have the shop check it out on Monday and probably do a front end alignment just to be safe.

I don't think it's a problem with the tires since I had them rotated and balanced at discount couple days ago and it didn't help or hurt anything. It was the same before and after. I also told the guys to make sure one of the tires wasn't bad and they said thee than normal wear they looked fine. And considering the tires have 25k miles on them roughly I doubt one just went bad from normal driving.

 

Don't touch the weights. If you think your Drive shaft is off balance, have someone balance it for you. If you f-with the weights, you can unbalance the shafts and make it worse.

 

I'm not going to actually move the weights. I'm going to unbolt the piece that holds the carrier bearing in spot and turn it on the splines and make sure that the weights on the drive lines line up. Someone mentioned in a post that they should be lined up when the drive shafts are bolted together. Mine are roughly 90* off. But I don't remember where they were when I took them apart to change the carrier bearing. Also don't know if maybe the dealer didn't line them up when they done the frame swap.

 

Remember where they are now, so you can at least get them back to there. Those shafts are usually timed from the factory,,but it might help. Can't hurt to try I guess. Never had a problem with mine so never took them apart. You would think that those weights should be 180° off from each other,,to cancel each other out and lining them up would create a severe out of balance situation.

The thing is you mentioned it goes away when warmed up. That's your starting point. Think in those terms (expansion/contraction).

 

Didn't think of it like that mod. I'll try lining them up and see if it gets worse. If it does or doesn't get any better then I'll do them 180* out. Hopefully one way or the other works.

 

Update:

Tried lining the weights on the drive shaft. No difference.

Put the rear end on jack stands and put the truck in drive. Doing 65-70mph couldn't see anything. Everything sounded and looked like it was running smooth.

Removed rear drive line and drove @ 65-70mph in 4-HI with just the front end pulling. Same situation except it did feel like the vibration came on slightly earlier. 55mph vs 65mph.

Changed out both front axle seals on the front diff because one was leaking. Checked out the bearings, brakes, cv axles, and everything else I could see while I was in there. Didn't see anything out of whack.

Had a buddy ride with me and told him everything that I had done and checked out. He was thinking possibly the tires. I'm about due for a new set. Down to about 10/32" on the BFG's (LT265/75/16) and since the truck is about to be back in North Dakota, figure I'll go ahead and put a new set on. Probably going with same size but in the Toyo MT's.

I'll see about the new tires tomorrow, and then take it in for a front end alignment to have everything checked out. Will report back if the tires make any difference.

 

Kinda what I thought initially. Old cold tires can jump and skip till warm

Not to rain on your fix-it parade, but I use to sell Toyo's from the Pac Northwest leader of those brand of tires. They are a OK tire,,not the best by any means. Make sure they zero out the wheels and tires when balancing,,get them perfect on the balancer to begin with. Have them check your wheels for runout (bent rim) as they spin them up. Explain to the tire shop that you are fighting a vibration and need a good tire person put on to your vehicle to check wheels and take the time to balance them out the best as possible. Those Toyo's really tread squirm when brand new. If your dead set on the Toyo's,,go for it. Just make sure they get them right when they mount and balance.

Funny that you BFG's would do that,,but it is a different tire size so that has a huge bearing on how a tire reacts to different conditions and vehicles. I run the BFG A/T's without a problem. 30x9.50's. Got 94K out of the last set and couldn't be happier with this new set. The best all terrain tire I have ran on road or off.

 

azaj..
Might take a look at this thread.
http://www.tacomaworld.com/forum/showthread.php?t=276853&goto=newpost

I've got similar problem, 02 DblCab 115k mile vibration every second or so 25-40 goes away when in 4Hi.
New Tires (Firestone Destination LT2), joints checked by mechanic recently, all greased, normal play in carrier bearing, no lift mods.

Good luck,
TL

 

Tlebel, how does your vibe feel? Can you feel it anywhere like floorboards, steering wheel, etc? Everything you describe sounds just like mine.

 

Just looked up under the truck and where the hole is in the bottom of the metal band around the carrier bearing there is also a hole in the rubber that goes all the way up to some thing metal in side its about a 1/4 inch in diameter.. is this normal?

 

no, it ain't normal...


sounds like you need a new center support bearing....I had this problem, solved with new bearing, pretty easy to do....

 

You could try swapping the front on to the back if you wanna run that set a few more miles to see if it changes or effects the vibes.

 

That's definitely drivetrain,,somewhere. Those unloaded axles/differential up front that are just free spinning when in 2wd is where I would start looking. Once you load them down by engagement,,it goes away. Unloaded and just statically spinning per say,,and it comes back. My train of thought is not always right, but it gets me close enough to find it.

 

My vibration is from 25-40, felt in the floorboards, not in the steering wheel. It goes away if I pop it in to 4hi. It is not cyclic and doesn't coordinate with anything like RPM, tire rotations etc, but does vibrate about every second or so.

 

I just ordered my new Toyota Center Carrier Bearing for the rear driveshaft. Will also check u-joints on the install and I will let you know how everything goes.