Drive Shaft Vibrations Solved Step-by-Step

Do you have a CB drop at all?

 

Yes I have a small one from toytec. The actual thickness of it I can’t recall and it isn’t listed on the website

 

Weird, I haven’t helped anyone that those two things didn’t help.

My last thought at the moment is shims. I have zero shins on mine.

 

How much lift is your leaf pack set at? Mine is at option 2. I do have a three degree shim

 

I’m on option 3. You could try removing it. Drive for two three days and retuque u bolts then go on a rough road and repeat. Over the course of a few weeks.

tuque should be 90 ftlbs. If you’re not using a tuque wrench you may want to try finding a friend that has one. 90ft lbs is a lot more than you think.

 

I’ll give it a go. I have been torquing with a good torque wrench. So you’re running no shim and small cb drop and your vibration free?

 

Yep! Really happy with my setup. On option 3 with no weight, it’s stiff and has way to much rebound for bumps around town but other than that no issues. I will see here in a few weeks I have a trip planned that will have 4-5 guys in the truck with a few hundred pounds of camping and mountaineering gear in the back.

 

Keep me posted, thanks for the input!

 

before and after CB Drop.


The carrier bearing drop made it worse, for sure. I’m definitely going to pull it out. I see why some of you are saying to flip the CB, but I’m still thinking a 2.5 degree shim should do the trick with the CB in the stock position.

Still looking for any solid advice.

 

I'll try. I put in a 3" lift with new leaf packs. I put in a CB drop. I had vibes on deceleration under 20mph. No vibes anywhere else though. Not bad but bothersome. I was going to run the angles on the impeller shaft but decided to put a 2° spacer in and see what it did. Fixed the problem for me. Before you pull the CB drop, I'd put in a 2° shim and see what it does. I can say being a GM factory master tech, retired, is chasing the angles on an impeller shaft is one hell of a rabbit hole. Hope this helps.

 

3rd Gen. I've been chasing the bad driveline vibes since I put in my Deaver leaf pack a few weeks ago. I'm not close to solving them. Playing with shims and CB drop distances. Recently the vibes have gotten worse and now the CB is howling at higher speeds. Can I kill this thing dead with a custom driveshaft of some variety? If so, what exact config should I discuss with the driveline shop?

 

I know that Tom Woods no longer makes a single piece drive shaft for the Tacoma. So, it might be hard to find unless you know of a shop that will make a custom driveshaft. Please post back if you find someone reputable.

Did you measure the angles prior to adding any shims and spacers?

 

I have several shops around here (greater Boston) that can make custom driveshafts. But I don't know what direction to point them in. Does anyone have those details on what I should be asking for? I see lots of solutions on custom driveshafts for 2nd Gen, but not for 3rd Gen.

Unfortunately no, I did not know to even measure the angles before installing the leaf pack. And once I did and the vibes were present, I was finding solutions to just drop the CB. So I was halfway through solving before I found this mega thread. I'm concerned that even if I get the angles summing out correctly, my CB or u joints are compromised and will need replacing. So if I have to get to that point and spend that couple of hundred, I'd rather just get a custom driveshaft for 2x that expense and kill this thing once and for all.

 

Are your U bolts torqued correctly?
Under torquing will create vibration.

 

Impeller shafts don't work well without some angle, and opposing angle. I would check your angle from your t-case to the front shaft of the impeller. I think the book calls for .08° or less, stock. A lot of people miss that, but it should never be 0°. I'm well aware impeller shafts are a bitch and I hope you get it figured out.

 

Options are to get a single piece driveshaft and let the driveshaft shop tell you what dimensions you need to measure. In theory, a longer driveshaft will have lower safe speeds it can spin so do some research if that will impact your normal driving speed.
Better option is take your driveshaft to the driveshaft shop an ask them to replace the center U-joint with a double carden joint (two U-joints mounted back to back) and shorten the rear shaft to compensate for the longer length U-joint and might as well replace the other joints and center bearing while they have it.

Go get estimates for both and report back how much they want for both option.

 

I’m going to second this. After my install of my leafs it took a few weeks to properly settle the leafs and U Bolts every few days checking that they are at 90ft/s. They move a great amount I got 1/2 turns if not more out of most the bolts the first time or two. Zero shims and not needed but I did do the cb drop because it was cheap easy preventive measure.

 

Apologies if I already brought it up. Following several threads on the topic.

I bought my 16, 2 yrs used and it already had shims on it. Do they come stock?
There was always a slight unbalanced vibe the dealer ignored and I never thought twice until I lifted.
2.5/1.5"
The vibe worsened. I did use the CB drop right from the start without trying otherwise.
After reading this thread I removed the CB drop and also noticed the drive shaft wasn't straight right to left. So I bumped that over to the d.s. as far as I could.
VIBE IS GONE!
I'm wondering do the shims come stock or did previous owner have a lift removed before resale and shim was left on?

 

I'm thinking my truck shimmed when it shouldn't have been?
Adding the lift made it correct as is but
then adding CB drop actually made it worse.

 

I don't think the shims are stock. I did a 2.5" lift, and tried a CB drop and shims, and various combinations with and without each, and haven't fully solved the vibes yet. I've just managed to move them around to different speeds. Takeoff vibes have remained the whole time, but my driveline vibes have changed from 53-56mph to now happening between 65-71 mph. Still searching for the magic combo.