Just a couple of suggestions that fixed my vibration issues - try checking gearbox mounting or look for a distorted tire rim - have the wheels been balanced? The drive shaft (we call them propeller shaft) can also be checked for balance in addition a worn pinion bearing in the rear diff can cause vibration
Humming Noise when Coasting. Update 9/6/23
- Thread starter Usterzai
- Start date
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did you ever resolve your issue?Update: After 15k miles, the vibration in my truck has been increasing gradually. I recently acquired another used transfer case to eliminate it as the source of the issue, confirming it's the new T-case was not the culprit. Despite replacing two rear drive shafts the issue does not seem to go away. However, if I rotate the driveshaft at the T-case of rear differential it will change the speed I get the vibration at. Driving without the rear drive shaft reduced the audible vibration significantly, but the truck still shakes at specific speeds (45, 55, 60, and around 70 mph).
Next step is to source a rear diff to rule out problems with rear diff.Absolutely baffled! Can anyone explain why changing the transfer case would cause the rear differential to go out? I've been troubleshooting my truck's vibration issue for past couple of months. Any insights or advice would be greatly appreciated!
- Thread starter
- #23
Unfortunately no. I initially thought the rear differential was the issue, but even after replacing it with a new OEM part from Toyota, the problem persists. The only component that hasn't been swapped out between the front and rear differentials is the transmission. I suspect the torque converter might be malfunctioning, particularly after 55 mph. Another possibility could be the output shaft of the transmission—perhaps it's bent or has damaged splines. When I changed the transfer case, the splines on the transmission output shaft looked intact, but I didn't check for any bends.
Brief background on how my problem started when I replaced the T-Case, and the trans fluid on the same day.
Now, my last resort seems to be replacing the transmission itself, though I'm uncertain if that will solve the problem. Every shop I've consulted has focused on the differentials and drive shafts, but all of those have been replaced with new OEM parts. I've even had two replacements under warranty, yielding the same results.
xeuxaz
SILVER Star
Before swapping the trans try 2 of these and see if it improves after 250-500 miles. Since you swapped trans fluid at the same time it could be the fresh fluid was the culprit.
Instant Shudder Fixx - Lubegard
www.lubegard.com
- Thread starter
- #25
I did try that as well. It improved things under 50, however the actual problem was still present. At this point it is either something very obvious that I cannot point out or something that cannot be fixed at all.Before swapping the trans try 2 of these and see if it improves after 250-500 miles. Since you swapped trans fluid at the same time it could be the fresh fluid was the culprit.
Instant Shudder Fixx - Lubegard
Right now my fix was to get another car and till I can fix this. Driving it daily with a huge audible and physical vibration after 55 and above was getting unbearable. Maybe one day I will be able to close this thread with positive news .
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xeuxaz
SILVER Star
I’m definitely interested to hear what resolves it once you figure it out!
Hey I'm curious if you figured out what was going on. I think I am just getting the start of this issue. It happens at slower speeds when I'm not accellerating or braking. I figured it was potentially a wheel bearing at first but after hearing the sound coming more from the front center of the vehicle, I'm not holding my breath. Appreciate any updates!
Land Shark
SILVER Star
When I had a "noise" when coasting and from the front center it was that my front diff bearings were toast. Drain the front diff and inspect the drain plug. Mine had big chunks of metal on it
xeuxaz
SILVER Star
My issue ended up being the front diff surprisingly. Slapped in a new OEM and it was good to go $1800 later.
Dang, at least you wont have to worry about replacing it again any time soon.
I'm currently still trying to figure out if its diff, u-joint, brakes (maybe warped rotor/uneven wear on pads), or the wheel bearing. I got a video of it I'll post here as well of the sound on my way back tonight. Going to tear into it tomorrow to see if there's any obvious signs of failure.. Sort of leaning toward brakes/wheel bearing due to the lack of consistency. The sound is relatively intermittent i can't reproduce it every time i decelerate, and sometimes it does it 1-2 times, sometimes its 10 times.
Conditions:
- only happens when foot is not on the gas
- happens with transmission in neutral as well as trans + Transfer case in neutral
- happens in 4hi/4lo, although less in high as there seems to be more load on the front end.
- Seems to occur if i go 30mph, and then let my foot off the gas, and it starts around 20mph. The video is between 18-20mph where it just kept going as i was on a very slight decline.
Video Below
xeuxaz
SILVER Star
I’d be suspicious of the wheel bearings.
Super sorry to hear about your issue here Usterzai. I'm tracking down a similar issue here.
Even though I've purchased two brand new OEM rear driveshafts, my latest theory is they are still the culprit. I did the swap around like you did putting the slip yoke by the TC and that made it somewhat better. Now trying to find a good driveline shop to check the OEM balance on these.
@Usterzai did you ever figure out your issue?
Even though I've purchased two brand new OEM rear driveshafts, my latest theory is they are still the culprit. I did the swap around like you did putting the slip yoke by the TC and that made it somewhat better. Now trying to find a good driveline shop to check the OEM balance on these.
@Usterzai did you ever figure out your issue?
- Thread starter
- #33
Unfortunately, my issue wasn’t resolved even after trying multiple fixes, including swapping the slip yoke position. I also considered the driveshaft balance but didn’t find any improvement after checking everything.
After some more troubleshooting, I’m leaning toward the transmission being the issue. I removed both driveshafts and ran the vehicle on the ground, and I still felt the vibration at around the same speed as on the highway—just at a lower intensity. My theory is that when the driveshafts are connected, the transmission vibration transfers to them, amplifying the issue.
Still working on a solution, but that’s where I’m at right now. Hope you have better luck tracking yours down! Let me know what you find.
Dang man! I feel like this is the saddest story on the forums. All I can say is thank you to your dedication for trying to figure this out. The amount of parts replacement you have done here is at heroic levels. It is wild to see how chewed up your TC bearing was.
I might have to try your trick of taking the driveshafts out and running it up.
Yeah that would be wild if that is the case, but to your point, maybe so! I wonder if that is my issue as well. According to the historical service records, my 250k mile truck had a reman trans installed at the dealer at ~150k miles. Or maybe they screwed up that install somehow?
- Thread starter
- #35
It's been a tough ride, and it's extra frustrating because it's my daily driver. 30,000 miles later, it's running, but I'm always fearing a massive, unfixable failure.
I forgot to mention that on hot days the vibrations are worse.
xeuxaz
SILVER Star
Nothing is unfixable.
Be very careful when greasing the slip yolks on our driveshafts. The common advice is to pump until it pushes out. However, this puts a huge amount of hydraulic pressure on the pinion bearing.
