21 Tacoma still vibrates after TSB.

I hear you on the GM products. I bought a brand new 1979 Sierra Grande 4 x 4 heavy duty with trailer package. The truck was more in the shop than on the road. After 1 year of fighting with GM dealer over problems they never actually did anything but give it back to me. Problems truck was running, rough leaked oil around the valve covers. This is what they would do wash the oil off the covers and change the plugs so it would run better. Once the warranty was over 1 year ( 12 months ) back then. I took the truck to a mechanic who found that the Cam was defect from day one it was alomst round not like egg shape that it should be. Phone GM HQ to complain and they told me to take to your dealer and they would check it out and if it needed replacing then they would cover if not it would cost 1500.00 to replace. Figured they would say that there is nothing wrong with it and soak me 1500.00 for opening it up so I told to go fuck their hats. Shorten the story the mechanic changed the cam and all the gaskets, labor for 500.00. I will tell you once it was fixed it was a great truck traded it in 13 years later for a Toyota Tacoma X cab 4x4 and never looked at another GM or American product again. Been trading in my Tacomas 93,98,2004,2008 and now I drive 2021 TRD Sport and happy with it.

 

I'm sure the weight helps. I've done some testing with mine with about 250 lbs in the bed and the 30-10 MPH vibe went away. Tested that speed range over and over on a smoothly newly paved road. The only good news about that is, it means it's likely driveline angle related and can be resolved with shims or.......... a shell. Lol

 

I don't doubt it. I think you're right in noticing that. Makes sense as the longer driveshaft might have less extreme angles. That's also why there's some one-piece driveshafts sold as a "solution" to this, Tom Woods, etc.

 

Same with mine. I rode in my buddies 2019 trd. You'd think you were in another manufactures truck. My sr5 is very smooth, and his trd was a way more old truck like feeling.

 

My 21’ is going in for the dealer to check my deceleration vibes in a week. I was supposed to get Fluid Film applied Monday but I think I may hold off until they confirm and hopefully approve the TSB. Glad to know Im not crazy with feeling the truck vibrating.

At first I thought it was possibly a warped rotor issue , but there is absolutely zero pulsing thru the pedal.

At my 5k the dealer told me it was normal since I had brand new AT Tires so I wasnt used to the ride. . Ive been driving Tacomas for 20yrs + . I know what tires feel like..F’n Jackasses.

 

Haven't had a problem with the braking vibrations but I have the harmonic vibration at 50 mph as well. Isn't all the time, and severity varies. I had the vibrations even extra weight in the back (Leer cap) and the addition of some helper spring hasn't changed anything. Checking bolt torques this weekend to see if anything improves.

 

Just to follow up, bolts all seemed ok. Was also due to rotate the tires so I went ahead and did that as well. Vibration is still there after doing both. With the morning temperatures getting colder it seems like temperature may play a role as the vibrations don't seem as bad during the morning commute.

 

throw some weight in the truck and the vibration goes away. also make sure your tires aren't over 32 psi. my vibration completely disappeared with about 400 pounds of cargo in the truck.

 

i always see Ram drivers with empty, clean beds. like they never even use it like a truck.

 

My vibration did not change with weight in the bed, up to 800lbs or so. This is because the joint that was shaking was the front joint, whose angle does not change appreciably with weight.

I've driven Ford and Chevy trucks lately, and I'm sad to say they drove better than my Tacoma does. Their engines/trans were much more responsive than my Tacoma, I'm sorry to say. I had clearly made up my mind that the Taco was going to go if I did not fix the vibration. Big Toyota guy here, having bought a BUNCH of new Toys over the last couple of decades, and it's a real shame I'm still not 100% satisfied with the truck- the shake is gone but the engine software sucks. I'm an OEM guy who does not like programmers but I've seriously thought about it on this one. The hesitation when accelerating is very annoying and not present on the Chev and Fords I've recently driven, but the durability and longevity could be in question on those, especially the Ford. My buddy's 2004 Colorado drives better than mine with over 200K on it.

 

I just had the “Stealership” do the TSB 0124-20 and told me it was fixed. Drove away and the vibration hadn’t changed in the slightest! I decided not to deal with their dumb asses any more and just address this issue on my own. I have restored a couple of Jeep CJs complete with lifts, so no stranger to drive-line vibration. I was just gonna order a Tom Woods 1-piece, but I pride myself on NOT giving up and doing it myself…necessity when i was in my 20s now it’s therapy from a desk job! I just finished this surgery Dual Port prescribes and what a difference! I did have to do a 2 degree spring shim to get the pinion angle to match up with the transfer case output shaft angle, but that was the easiest part. If you don’t have the skill or tools to do this…find a buddy who does. Spicer knows their shit! Toyota….not so much. You will be glad you took the “leap of faith!”

 

Still dealing with some of this myself even though I only have a helper spring in the back. I installed some 2 degree shims (smallest I could find), remeasured all of my angles and have found the following (all measured from horizontal): TC 2.9 down, 1st shaft 5.1 down, 2nd shaft, 5.0 down, Pinion 3.8 down. From there my WA's are 2.2, 0.1, 1.2. From what I understand, if I could drop the pinion by a degree from the current positions my first and third angles would match and all would be right with the world, correct? Swapping out the 2 degree shims for 1 degree should do the trick

 

Ok, I think you’re headed in the wrong direction. Let me see if I can explain this. If your pinion flange is indeed 3.8 down the relationship of that flange to the TC flange are WAY off. Because your diff sits much lower than your TC and the TC points down, in order to achieve those two flanges pointing in parallel, your Pinion should be “up” not “down”. Check angles again measuring ALL from the passenger side. If your pinion flange is indeed pointing down, that would put you 6.7 degrees out of parallel to your TC…that won’t get you were you want to go. Also, Spicer requires all driveshaft ends to be at MINIMUM 1 degree. Your 1st and second shaft are at .1. That is actually to close and not allow the joint to swivel at all. This in itself will cause vibration and premature wear. Let me what you find on the diff pinion flange angle and I can coach from there.

 

@Retirement-Ready , thanks for the response. I think the wording in my first post was inconsistent with convention, sorry. The pinion points up 3.8 degrees out of the diff. I originally meant that it was 3.8 degrees down from level, in the same sense as the shafts and TC.

 

Ok, with that resolved, look at Dual port’s notes from Spicer. I’m still concerned that you don’t have enough angle difference where your two driveshafts meet. I’m going to assume that the joint at the carrier bearing isn’t actually breaking the opposite direction like your drawing shows. I’m not poking fun…it’d better than I could draw, but it should still be a “downward progression” not inverted. So let’s follow that assumption…my concern still lies in that .01 angle there, its to small/slight. Problem is, following the assumption, you cant shim the carrier up, only down. This where i believe Dual Port’s and my own problem got complicated…the only way i found to get more angle there at the carrier bearing joint I had to start looking at shimming the diff down or lowering the TC. Keep in mind you have to maintain those two flanges running parallel to each other. If you lower the front of the diff you will be getting closer to exact alignment of the two flanges, and increasing the angle at the two driveshaft ends. Watch the angles of any two shifts and remember not under 1 degree and preferably not over 3. End the end…I had not other choice on mine but to lower the TC mount like Dual Port. Do your math from one end or the other and if you get a clear path with good numbers by lowering your diff, then by all means do that first! It’s an easier path, but I agree…1 degree shims are as “rare as hen’s teeth”

 

The drawing is the same as the actual shaft. After measuring multiple times, the first shaft is actually steeper than the second. Without moving the transmission around the only way to get a bigger angle in the middle is to drop the carrier, flattening the second drive shaft, increasing the first working angle and decreasing the last.

I guess this weekend I'll take out the shims and just mess with the CB.

 

Question for Dualport and Retirement-Ready, what else does changing that mount affect? It tilts the entire engine, tranny and transfer case slightly, correct? Just wondering if there’s any concerns with that on other components.

I really need to get all these measurements and dive into the Spicer manual but that just sounds miserable and I’m pretty OCD so might go down a very dark path!

I took a little different approach with diagnostics. I knew weight in the bed helped. Drove around extensively with 250 lbs in the bed and the vibration was gone at all speeds. I measured my pinion angle with and without the 250 lbs and it changes by 0.5 degrees. My logic is, all I need is a 0.5 degree shim to fix this, if I stay at stock height.

My problem is, I don’t like the ride of the stock shocks. Too stiff and jittery so I want to replace them. I was going to go with Fox 2.0s (snap ring type) with my stock springs, 1.0” lift up front and a 0.5” block in the rear. The rule of thumb is, you need 1 degree of pinion shim for every inch of lift. So that’d be a 1 degree shim in my case. Half degree to account for the lift block and half degree for the vibe that was there before the lift.

I could just go for stock height springs but changing out shocks with zero lift just pains me!

 

Yes, you're adjusting the position of the whole powertrain but it's very minimal, I saw/felt/experienced no issue with anything by dropping the trans mount a half inch. The most likely problem would be exhaust system or fan rubbing the shroud, but it's well over a year and no issues since then.

Good Luck!

 

My 2022 did that vibrating really bad. They replaced the leaf springs and added a steering dampner it fixed the problem. I traded it in for my 2023 and this truck is real smooth no vibrating at all from the factory.

 

I've got in on my 22 DCSB OR MT. Mostly decelerating from 25-10 mph and especially noticeable when going downhill and stopping. I haven't bothered with taking it to the dealer for the TSB but perhaps it might be worth it. I yet to get underneath and measure angles to determine how far things are out of alignment and where. I'd prefer to address the actual issue rather than symptom which appears to be the direction Toyota seems to be taking. I'd like to know what is different about the leaf springs that Toyota employs in the TSB. If my problem is the angle off of the transfer case as was shared here by another member, that likely won't have much of an impact.