Help diagnosing 42-46 mph vibration

Hi guys, looking for some help in diagnosing a worsening, pulsing type of vibration on my 2009 off-road (4.0 / 6-speed / access cab). It is most noticeable accelerating, decelerating, or coasting in the 42-46mph range. It occurs in 4wd and 2wd, and happens in any gear (3, 4, 5, or 6) and in neutral.

So far, I've replaced the following:
-Front wheel bearings using OE bearings from 05Taco4x4's press service. Also replaced both knuckle seals
-Needle bearing using ECGS bushing, new OE CV axle seal
-3x u-joints in driveline with OE spicer greasable u-joints
-carrier bearing using OE bearing direct from Toyota
-inspected driveshaft for any recent damage that could have thrown it out of balance, but nothing obvious.
-I also swapped off my Blizzak snow tires and put on my AT tires recently to rule out tire noise/vibration.
-All gear oil (f & r diff, t-case, transmission) was new 10-12k miles ago, and I just replaced the rear diff gear oil again to rule that out.

In the last 20k miles, I replaced both CV axles with OE Toyota axles and all front & rear suspension components with OME & Bilstein components, resulting in a 2-2.5" lift front & rear. I also installed the OME driveshaft spacer/drop when I installed the suspension. No differential drop. No vibration issues for the first ~19k miles after suspension upgrades, just started somewhat recently. Alignment has been checked and is fine. Always use a torque wrench for all of these repairs and am pretty confident in my DIY abilities.

I've jacked up the rear of the truck and tried to check for rear wheel bearing play, but there is no obvious play. I've read that wheel bearings on these trucks will start to make noise/vibrate long before you can detect any play. I suspect that is my issue, but the rear wheel bearings appear to be more of a pain in the ass than the fronts (or at least require more specialty tools). Is there anything else I should take a close look at before I continue throwing parts at this truck? I've searched through tons of old threads, but it seems that most people solve a similar issue with either front wheel bearings or ECGS bushing. Thank you!

 

Have you checked the rear pinion bearing?

 

I have not- any suggestions for how to do that? When I changed the rear diff gear oil yesterday, the magnet came out perfectly clean, not a spec of metal/debris.

 

Grab the driveshaft and make sure there is no play in the bearing.

 

What wheels do you have/were the blizzaks and AT tires mounted to the same wheels or are they 2 separate sets?

 

Blizzaks are on OE steel wheels from a different Tacoma, AT tires are on OE alloy wheels. So two separate sets of wheels, both sets of tire-wheel combos recently balanced. Blizzaks were new earlier this winter and the AT tires have 15-20k miles, but were rebalanced last summer not long before I swapped them out for my snow tires.

 

Thanks! I'll give this a shot.

 

I think it could be your pinion angles on your driveshaft. Get a tom woods 1 piece drive shaft

 

Ah okay definitely doesn't sound like that could have to do with wheel/tire then. I always like to start with the easy stuff first, good luck!

 

Before going that route, I would confirm your pinion angles and see if maybe you can correct with a shim under your leaf springs. I don't believe Tom Woods makes a single drive shaft for Tacoma's anymore (not saying you cant find one second hand) because they determined that a single shaft wasn't the end-all-be-all fix for shaking. @sbMT if you've confirmed that your CB and your U-joints are good, along with the rear pinion bearing, I would check your pinion angles. Confirm that your tires are balanced and at the correct PSI. Additionally, your drive shaft may have thrown a weight. You can remove them and take them to a shop and they can confirm that your drive shaft is harmonicly balanced. When you changed your U-joints and CB, did you ensure that you reassembled the drive shaft exactly how you took it off? Like did you put alignment marks on the shaft to confirm that they aren't out of phase? I'm just spitballing here.

-J

 

Quick update on my situation in case anyone here or in the future ever finds this thread helpful. I ran out of time before a 2000 mile Utah desert trip in March to keep chasing this. I rolled the dice that my vibration issues wouldn't get worse or some component wouldn't fail entirely and went on my trip as scheduled. All went fine, even with 100s of miles of rough backcountry driving.

Got home and reached out to Headstrong Offroad with some axle shim questions. I had purchased my Dakar leaf springs and other lift components from them a few years prior. They encouraged me to give it a shot, and that it's sorta a game of guess-and-check. So I ordered their 3 degree axle shim kit, received and installed today. My vibrations are at least ~80% better!
I may try removing my carrier bearing drop (because it takes 5 minutes) to check whether I overshot on my axle shims. Depending on that outcome, I may try a different angle shim. But overall I'm super pumped that I'm on the right track and the vibrations are now nearly imperceptible.

Thanks to all of you who weighed in and tried to help me! Happy to return the favor if anyone has questions.

 

I'm glad it worked out for you but that link I posted in my previous post has a calculator on it to help dial out your specific shim. I'm glad 80% better is an improvement, but with a bit more finagling on your end, you should be able to get that closer to 98% better.

-J

 

Reviving my old thread in case someone can help me stop beating my head against the wall. Still chasing a vibration at 41-42 mph and again (though slightly less severe) at ~81-82 mph. Truck is a 2009 access cab, 4x4, manual transmission, v6. Vibration happens under acceleration, deceleration, and when coasting. Happens in 2wd and 4wd and in any gear. The vibration started rather suddenly ~20k miles after I installed a small suspension lift front and rear (OME & Bilstein)-- seems weird to me that this would be the cause if everything was perfect for 20k miles...?

Below is what I've done so far, roughly in this order:

Replaced needle bearing with ECGS bushing
Replaced front wheel bearings (OE)
Replaced 3 u-joints in the driveline (OE)
Replaced carrier bearing (OE)
Tried different tires and wheels, rebalanced old tires, replaced old tires when they wore out- no changes
Replaced rear diff with an assembled 3rd member from ECGS (to rule out pinion bearing failure)

After none of the above maintenance made any difference, I've been convinced that it's in my driveline angles. I've since tried many different combinations of axle shims (3* and 4*) and different amounts of carrier bearing drop. None of these adjustments have made a meaningful difference in the vibrations, which has me questioning whether it's driveline related after all. I think I now have my driveline angles pretty close (transfer case & rear pinion within 0.6* of each other). I think my east-west alignment of driveline is right on.

No vibrations at other speeds, and no axle-wrap induced vibrations at takeoff. All drive-line and suspension related bolts are torqued to spec and nothing appears worn out.

Rear wheel bearings have no noticeable play and sound pretty smooth when I spin them with the truck jacked up. No noticeable difference when turning one way or the other, which has always been one telltale sign of failing wheel bearings for me.

I'm sorta at my wit's end trying to figure this out. Could there be some sort of weird harmonic thing going on due to odd wear/pitting/etc in the drum brake assemblies? Something internal to the transmission or transfer case? Anything I'm missing?? I'm about ready to give up and take it to a shop, but I don't think any dealer or even toyota specialty shop will put the time into this that I have. Maybe I should just live with it and see if it gets worse? Thanks in advance for any help!!