*UPDATE* - It's Definitely a Drive Shaft Vibration...

So I recently installed brand new tires and a mild lift on my 2009 Tacoma DCSB. The tires are 265/70/17 BFG All-Terrain KO2s and the lift consists of Bilstein 5100s, OME 885 coils and a 1/4" Driver's Side Spacer up front and OEM 3+1 Recall Leaf Springs with an Icon 3 Leaf Progressive AAL kit installed in the rear. I left the factory overload spring installed with the AAL kit.

Overall, I'm incredibly pleased with the way this setup looks, rides and performs on the street. I saw just over 2" of total lift and the new suspension is a little stiffer than the OEM TRD Sport suspension but it's not rough by any means. The nose of the truck no longer dives during braking, it feels better in corners and in general, I feel much more connected to the road. The tires are also a huge improvement over the Bridgestone Dueler Revo 2's they replaced. The BFGs are very quiet, stick to both wet and dry roads and are extremely comfortable. However, with all of that said, after driving on this setup for a few days now I've noticed the truck has a very slight shudder from takeoff up to about 10 miles per hour and then randomly I'll experience vibrations up to 40 miles per hour. It doesn't seem to happen every time and I haven't noticed any other vibration or shudder at any speeds above 40 mph. Also, just to note, switching to 4H doesn't impact the vibration and I don't feel the shudder in the steering wheel or the pedals, as it seems to be coming from the rear of the truck.

*UPDATE 06/13/2016*

After doing a ton of research I've narrowed the problem down to a drive shaft vibration. I decided last night to crawl under the truck and measure my drive line angles before making my next move. As for the science behind drive shaft angles, I wanted to include a quote from another member about how to properly align your drive shaft in order to minimize or eliminate vibrations that has appeared in more than one thread about drive line vibrations:

From what I can tell, this particular member isn't active on the forum any more but his advice seems to be solid based on the comments other members have posted in those other threads. From what I could gather, method number one typically works the best for eliminating drive line vibrations. With that said, here are the measurements I got last night:

TC Output: 0.0° (I calibrated my angle finder on this angle)
First Shaft Angle: 5.5° down
Second Shaft Angle: 5.2° down
Pinion Angle: 3° down

Using the logic posted by badger years ago, it appears that I will need to purchase and install a pair of 3° axle shims in order to align the TC Output Shaft and the Pinion Shaft in parallel. Once that is complete I will need to remeasure my two drive shaft angles and adjust the carrier bearing as needed in order to keep the two shafts in a straight line (within less than 1° of each other). I'm going to order the axle shims right now as well as a CB drop kit (just in case) and I will report back once I have the axle shims installed and have my new measurements.

*UPDATE 06/21/2016*

I decided to forgo the axle shims and try to correct my drive shaft vibrations using a CB drop alone. After experimenting with various intervals of CB drop using one M10 fender washer at a time I found that 5/16" drop gave me the best results. I actually switched out the 8mm OME CB drop spacer in favor of three of the fender washers as this combo was dead on 5/16" whereas the 8mm spacer is just a bit over 5/16". I didn't have enough washers to try anything over 5/8" so I wasn't able to test the drop up to 3/4" but I don't know if that would help me anyway. At just over 5/8" (the OME CB spacer plus three fender washers) I experienced vibrations at higher speeds (60 mph+) which I had never experienced before. I settled on using three fender washers as the 5/16" spacing eliminated all of my deceleration vibes and greatly reduced my takeoff vibrations. Right now I only feel a "shudder" on slow takeoffs between about 5 and 7 mph. If I accelerate hard I don't feel anything and overall the truck feels the most like it did on the factory suspension with this setup. For now I'm going to leave it alone for a few weeks and see how it feels. If I can get used to it I'll leave it alone. If not, I'll likely spring for a custom one piece driveshaft sometime later this summer. I don't plan on getting rid of this truck for a long time and I'm starting to think a new driveshaft is the best option for eliminating vibrations long term.

*UPDATE 06/30/2016*

Bit the bullet and installed the 3° axle shims last night and removed the 5/16" CB drop. As of right now the shudder at slow take off between 7-10 mph is still there (it's much more pronounced on an incline) but most of the other noticeable vibrations have diminished. I'm going to crawl under the truck tonight after work to measure my new drive shaft angles and decide if raising or lowering the CB will help. I'm hopeful that the shims plus an undetermined combination of CB spacers will get my measurements in that "perfect range" where the vibrations disappear but we shall see. I'll probably take measurements for a new one piece drive shaft while I'm under there as well, just in case.

One more thing I'd like to point out. The amount of noticeable vibration varies greatly from a full tank of gas to empty. The extra weight in the rear really does reduce the overall vibration I can feel. Makes me wonder if I shouldn't just load up the bed with ~200 pounds of sand bags and call it a day...

*UPDATE 07/01/2016*

Ok, so I seriously can't make this stuff up...

As previously mentioned in post 68, I installed the 3° axle shims with the skinny side facing forward (as recommended by pretty much everyone) the other night. Well, last night I crawled back under the truck to measure my angles since I was still experiencing the take off shudder and some low speed vibrations. I was expecting to see the TC output angle and the pinion angle within .5° of each other and was fully expecting the two shafts to be off by more than 1°. And man do I wish that's what I found...

Instead, here are my new measurements:

TC Output: 0.0° (I calibrated my angle finder on this angle)
First Shaft Angle: 5.5° down
Second Shaft Angle: 4.2° down
Pinion Angle: 6° down

So yeah... as you can see, installing the 3° axle shims with the skinny side forward just doubled the difference between my TC output angle and the pinion angle.

At this point I'm not even going to mess with the CB drop but hopefully I can find the time to turn the shims around sometime this weekend. Based on what I've done and seen thus far, logic tells me that reversing the shims should result in a near 0° difference between the TC output angle and the pinion angle (ideal scenario) and that from there I can shim the CB to get the two shafts within 1° of each other. I'm not going to hold my breath but we shall see what happens.

In the meantime, if anyone wants to try to explain the math and physics going on with my truck, I'm all ears. I'm beyond confused right now and just about ready to say f*(k it and buy a Tom Woods one piece axle and be done with it...

*UPDATE 07/05/2016*

Alright, I give up...

Tonight a friend of mine helped me reverse the 3° axle shims. After we were done and the truck was back on the ground I took some new measurements.

TC Output: 0.0° (I calibrated my angle finder on this angle)
First Shaft Angle: 5.7° down
Second Shaft Angle: 6.2° down
Pinion Angle: 0.7° down

As you can see with the shims reversed I got the TC output angle and the pinion angle below 1° and the first and second drive shafts are within .5° of each other. I was really hoping for the difference between the TC output and pinion angle to be much closer to 0° but it is what it is... Anyway, with this new setup my takeoff vibration is still there and now I have a truck shaking vibration at 30 mph both when accelerating and decelerating. This combo might have resulted in the worst vibrations I've experiences thus far and it was incredibly disappointing. I even tried to add the 8mm OME CB drop kit and when that didn't help I took it as far as I could with my fender washers (5/8") and the truck still shook horribly around 30 mph. At this point the 3° axle shims are coming out first thing tomorrow and I'll be going back to the 8mm CB drop for the time being. That combo gave me the best results I've had thus far but it's still far from ideal.

In the meantime I'm going to reach out to two different local drive line shops to get estimates on a custom one piece double cardan shaft. I hope to have a new 4 joint drive shaft installed within the next week so that I can put these awful vibrations behind me and get back to enjoying my lifted truck.

Thanks to all that have tried to help me with this issue and while I know this whole drive shaft thing is a science and that if I messed with enough combinations of shims and CB spacers I could eventually cure the vibes but with my OEM drive shaft and CB being 7 years old and having 65K miles on it, it's just not worth the time and effort for me to continue down that road.

*UPDATE 05/17/2018*

I know it’s been close to two years but I wanted to give this post one last update. At just over 90k miles on the truck (the last 25k or so lifted) the OEM CB gave out on me. It was squeaking like crazy and had so much slop that my rear drive shaft was vibrating at almost every speed. Instead of replacing it with another one that would eventually fail and leave me with these messed up angles I opted to have a custom one piece rear driveshaft built and installed. I just got the truck back on the road yesterday and all I can say is wow, the new driveshaft is a game changer. All of the vibrations are completely gone and the truck hasn’t felt this smooth on the road in the 3+ years I’ve owned it. For anyone else who is experiencing driveshaft vibrations (lifted or not) I’d highly recommend spending the ~$500 to have a custom one piece rear driveshaft built. I’m disappointed it took me two years to do it but I’m super happy I did.

 

You shouldn't get either on a slow start. On a fast start is where the stock springs will bend under pressure and feel like a slipping clutch as they load and unload pressure - With AALs you shouldn't get any axle wrap, even on quick starts. Again, you should not be experiencing wheel hop on slow starts, as you aren't giving it enough skinny pedal to break the tires loose.

You've lifted your truck and changed the drive line angles. I suggest a carrier bearing drop. What you are feeling is a binding in one of the u joints. Failure to remedy the cause will result in premature failure of the u joint.

 

That's cool, is that homemade or something you can buy?

 

Custom made in my garage/shop to fit my truck. dramatic improvement. Lots of options for "store bought" traction control if you do a little research.

 

Traction bars will fix your problem.

 

I'm still on stock springs and have a manual transmission. I can create axle wrap on demand. I very rarely get axle wrap thoug, because I start out slowly pretty much all the time. Slow starts will not cause axle wrap, therefore a $10 CB drop (or go buy washers and longer bolts at NAPA). Traction bars are not going to help your particular problem as you described it.

 

And this is exactly why I'm so confused...

I've owned and driven enough FWD cars with more HP than they could successfully put to the ground so I'm very familiar with how wheel hop feels and sounds. And I'm telling you, with my windows down it sounds like my rear wheels are "hopping" and not sticking to the pavement when the shudder occurs... Axle wrap is new to me but I agree that the AAL should minimize the noticeable effect. As for the drive line vibration, if the tiny shudder I'm feeling shortly after takeoff and before I get to 10 mph is in fact due to bad drive line angles, I'm not about to start randomly guessing which remedy to use. For now I'll need to try to set aside some time to measure my drive line angles and try to figure out if moving the carrier bearing will potentially fix the issue... I've also been reading threads about axle shims and the CB flip so I know there are multiple ways for me to manipulate my drive line angles if that's truly my problem. After all of my research I had pretty much ruled that out seeing as I don't feel vibrations at any other speeds and because it doesn't happen with every takeoff.

 

Not to start a pissing contest, you can't start slowly enough to not have your pinion gear rise - it's the degree of rise (axle wrap) that either is or isn't a problem. I have over 20 minutes of driveline video that documents - if your truck is moving the pinion angel is changing - exacerbated by lifting (stock suspension)and / other suspension changes.

 

If the pinion angle when the gear has risen is the problem wouldn't, in theory, axle shims help correct the angle enough to minimize axle wrap and potentially remedy the slight vibration I'm feeling?

 

I had the exact same problem after my lift, tsb leafs with icon aal and no overload, i ended up dropping the cb 1/2" and retorquing the u bolts to 100flt lbs no more problems.

 

I'm guessing that what you are sensing is a small amount of tire bounce from the stiffer suspension on initial acceleration. I can't see pinion angles being the cause, because there is quite a bit of latitude in Tacoma drive lines - think about all the different lifts that are used in this forum. Anything under 3" is pretty bullet proof. With stiff tires, and a more robust suspension, your truck is going to transmit little road irregularities the minute it starts to roll at low speed. Once it picks up speed, its smooth. Don't worry about it. Its a truck with a lift. The important thing is what it feels like at 90 mph passing a convoy of semi's on the interstate? If its smooth enough to sip on a hot cup of coffee at the same time, you're golden.

 

There are literally hundreds of posts on this forum discussing this problem - 58 Siesta has given you his opinion - good luck

 

I can't help but wonder - if all these lifts are so "bullet proof", why are there literally hundreds - maybe thousands (yeah, just type in driveline vibration in the search box) posts on this forum dealing with drivability issues after a lift? Not looking to start a pissing contest, just curious.

 

I'm genuinely curious, and don't have experience with an AAL on these trucks. Doesn't the AAL provide enough support to prevent noticeable axle wrap? I understand you can't stop the pinion from shifting, but I thought you'd get added support over the length of the leaf pack. I understand that my Dakars will not even prevent the pinion angle from changing under load, but it shouldn't be bad enough to feel it in the driver's seat, right?

The slow start comment is my reason for feeling strongly about an internet diagnosis, not just feeling froggy.

The engineers put in a whole lot of time to make these things run smoothly. We buy them and eff with a finely tuned machine - then wonder why it vibrates, squeaks, and wanders down the road.

 

I have the same lift, tires and the same vibration from takeoff. I'll be checking my driveshaft angles this weekend.

 

You only had a vibration at takeoff and no other times when driving?

Because I've had my truck up to 80 mph without any other vibrations other than the one at takeoff... If dropping the CB using washers or a kit eliminates the shudder I'm all for it. Like I mentioned in my last post, I guess I'll climb under the truck and measure my drive line angles to see if a CB drop should help my situation.

 

yep it was only on takeoff. tightening the ubolts helped alittle and dropping the cb got rid of it all together.

 

I second the CB drop. I went to the local true value and got some 1/2" stainless steel bushings and used them to drop. Definitely helps straighten the drive angles back out. However, didn't fix the shudder, still had a vibration. Took me a while to figure it out but after much research I know what it is, just haven't fixed it. When you feel the shudder, try switching to 4H, if it goes away in 4H but comes back when you switch back to 2H, then its your driver side clam shell bearing (needle bearing). You can either check this out http://eastcoastgearsupply.com/i-8536125-toyota-8-clamshell-bushing-eliminates-needle-bearing.html for a $60 5 hour fix or you could replace the stock clam shell with aftermarket for $1kish.

However, you stated you feel the shudder in the rear so this may not be your case but figured I'd share. Good luck!

 

Thanks for the input but I already tried switching the truck to 4H and the shudder at takeoff was still there...