Tracking down an odd vibration

2002 SR5 access cab 4x4 5Spd with 143,000 miles if that helps!


So I'm trying to track down a vibration in the truck. Its most noticable at about 75 mph and 3k RPM in 5th its the most noticable. Putting it in neutral even at those speeds cause the vibration/shake to subside. It's most noticable in the peddle, shifter, and steering wheel in that order. However it's a noticable bounce in the truck looking at things shake in the passenger seat. Logic would say it's a wheel imbalance but it has persisted through two separate sets of wheels and tires, multiple mounts and balances as well. Recently the following has been done if any of them stick out as a likely culprit:

Lower & Upper Ball joints
New front coilovers (51000s and OME 2884s)
Upper and lower control arms
Sway bar link ends
CV axles
Inner and outer tie rod ends
Steering rack bushing (only the larger outer bushing)
Front Calipers

These were all done at about the same time so I can't tell what caused it to start. I've had 3 different alignments and it's in spec so that theory seems out. The only other thing I can think is driveline. There is a little play in the carrier bearing the U-Joints seem fine but I've never seen a failing one before so that's plausible. Anyone have any ideas or suggestions to check/diagnose?

 

Play in the carrier bearing is normal.

How often do you lube the driveline? (grease all zerks on front and rear driveshafts, slip yoke, etc.)

When does the vibration begin to show up, at what speed?

Is the back lifted, and if so, what method used?

The note about shifting into Neutral and it goes away could point to any thing between the transmission output shaft back on the driveline.

 

I have never lubed the driveshaft. I've owned the truck for about 3 months and about 5000 miles now. However, when I went to check the U-Joints and carrier bearing I didn't notice any zerks. Granted that was a quick look checking for play on just the joints and not at the slip yokes.

It seems omnipresent, however it really becomes noticable from about 2800rpm on in any gear but is definitely more noticeable in that range at highway speed as opposed to 3k at say 35mph in 3rd.

The back is not lifted, I'm sitting on the parts to do the rear just waiting until I lift the bed off to do some other work in the meantime. It sits fairly level as is without a noticable rake.

That's what's making me think along those lines as well. It's not an instant end to the vibration as soon as its in neutral but it definitely tapers off quickly. My biggest fear is that it could be an unbalanced flywheel.

 

What kind/size tires?

and why the fuck did you only replace ONE rack bushing?

 

You’re describing it as engine speed / load dependent. Putting it in neutral makes it subside. So I would focus on the rotating assemblies. If it were engine related, I would suspect a misfire which would trigger a code, you did not report any codes. If it were transmission related, I would be thinking torque converter / flex plate for autos, yours is a manual I’m guessing by the 5 speed description and it being an 02. But you say “put it in neutral” (more of an automatic trans terminology) which I’m interpreting as push the clutch in and unselect whatever gear you’re in. Clutch can get worn and create some vibrations at end of life, but generally they shudder towards the end and fail to grip, they don’t just develop vibrations. Driveline would be next, bad U-joint, thrown balancing weight, bad carrier bearing, bad pinion bearing etc. some things that also come to mind but don’t fit your description are warped rotors (you replaced a caliper recently, what about rotor and pads?) or an out of round drum, or dragging rear brakes. Driveline usually shows up most in the seat though, not in the steering wheel.

 

May unrelated, but this morning I found that my driveshaft had thrown a weight. https://www.tundras.com/threads/wha...-gen-tundra-today.2558/page-2268#post-3836735

 

265/75R16s

And totally valid question. When I did the tie rods the bushing mount on the passenger side was completely rotten and rusted in half. So obviously that needed replaced. I went ahead and grabbed a new bushing from Toyota when I picked up the bracket. I do have a box of Energy Suspension bushing sitting in my garage i just need the time to replace the other two bushings.

That has been my train of thought too. Correct it is a 5 speed Manual, the clutch was replaced about 3000 miles ago and feels tight. Yes "neutral" being just deselecting whatever gear it was currently in. The same effect happens but slower just by letting off the accelerator. It does have a bit of a "vibration" around the 3k RPM in neutral parked but its a different feeling. The motor mounts still seem good as the engine doesn't flex during tests running it up to that RPM range. I've also read the 5vfe just seems to have a resonant vibration in that range. The timing belt was done in 2018 at 98K miles according to the sticker so I'm less likely to believe its a harmonic balancer. I haven't done the rears yet, I'm sitting on the parts I just haven't had the time or cooperating weather when I did have the time. Maybe I'll get those knocked out this weekend. I would say you can feel it through the seat but it feels the most noticeable at the places I'm "connected" to the truck through the pedal and then steering wheel.

I'll do some more digging on the driveline as that has been my thought process too, that's one thing I don't have experience with diagnosing but maybe something will jump out at me looking again.

 

Still working my way through this. In my continued search I stumbled across a thread on Tacoma World with someone describing the exact thing I'm experiencing starting with the CV axle replacement which is also when mine started. Unfortunately, it's an older thread and no resolution was found. As this seems to be something both Tacoma's and Tundra's experience I'm wondering if someone hear has had that problem and what they did to remedy it.


The thread in question:
https://www.tacomaworld.com/threads/bad-vibration-after-cv-axle-install.806342/