Squeak and and vibration

[Gurubreed]

ok i recently started getting a vibration around 35-40mph stops after that and around 65 it felt like i was driving on the rumble strip on the highway.. so the next day i figured it could be a something with the drive shaft so i greased all the zerks... now i have a mild squeak only when i'm on throttle...vibration still there. then i went back under and noticed a little rust in the spider bearing on the rear u joint... i guess it would be the spider bearing squeaking... could use some advice... oh yeah it's a 98 T4R 4wd the video below is what it sounds like... not my video

<iframe width="420" height="315" src="http://www.youtube.com/embed/DJXja7fEMmM" frameborder="0" allowfullscreen></iframe>

 

[fasterdammit]

Unfortunately, I don't have anything of value to add as far as a solution, but I just encountered something similar in my '00 SR5: when I hit 60mph it'd start with this real low-grade humming/grumbling. I didn't feel it in the drive or in the steering wheel, but I could certainly hear it. Drop back to 55 and it's gone. I haven't greased anything yet, but was going to put this same question out there. What the heck?

 

[Gurubreed]

humming i would think would have something to do with a wheel bearing or rear diff. i know they have rear axle seal problems so your gear oil can get low...take off you back wheels and if you have drum brakes pull the drum off and see if there is oil in there

 

[fasterdammit]

Nah, it's clearly coming from up front (should've mentioned that originally). It's odd because it's literally right at 60mph (indicated, so real speed that's probably more like ... 66-68 in my truck): above it, grumbling; under 60, nothing.

 

[brian2sun]

Sounds like maybe your tires are just getting worn out of round or they aren't balanced anymore.

 

[Gurubreed]

Nah, it's clearly coming from up front (should've mentioned that originally). It's odd because it's literally right at 60mph (indicated, so real speed that's probably more like ... 66-68 in my truck): above it, grumbling; under 60, nothing.

also your front rotors can be warped.. i heard that's pretty common... i think your front wheels are supposed to be torqued on at 75 ft lbs... if not they can warp..

 

[fasterdammit]

also your front rotors can be warped.. i heard that's pretty common... i think your front wheels are supposed to be torqued on at 75 ft lbs... if not they can warp..

That I do need to check, but w/ my sneakers (315/70R16 Nitto Grapplers), I should be torqued to 90lbs apparently.

After some more miles, I'm worried it's an output bearing or something not related to the wheels, because it's not consistent - which is confounding: it's not related to a certain speed, or a certain gear, or a certain ... anything. It's almost like an unbalanced drive shaft, except ... inconsistent. It only seems to appear when I'm just getting on the gas (i.e. after coasting, in neutral) or when letting off the gas and letting it trail-brake ('engine braking') - which leads me to the power output; i.e. changes in getting power to the wheels makes it occur. It's making me nuts; but I'm going to throw the towel in & drop it off @ my buddy's shop this week.

 

[Gurubreed]

when you figure it out post what it was and the solution...

 

[theizzardking]

wheel bearings can do this as well, it is quite common for the sound to only be produced at hiway speeds, happened to me a few times on various vehicles.

the shaking of the truck has me a bit more worried though as that tends to be more of a diff thing as opposed to a wheel bearing, you know the difference between a ring and pinion making sound with teeth then a bearing that has none, just balls in a cage. the shaking if bad is either your drive shaft binding up or the ring and pinion. i can;t see a wheel bearing shaking the whole truck to much, it seems the sides would blow out of the cage if shaking to terribly.
where as teeth running improperly across the top of a pinion ring could easily cause the truck to shake and rock, just throwing some ideas out there.

 

[fasterdammit]

Fixed mine: rearmost U-joints on the rear driveshaft

So I was wrong about the front end being the issue; but after some more miles and tooling around town I was convinced it was something to do with the power output. Because, any time the power to wheels (in 2hi) changed, the vibration would really act up. In other words, getting on the gas or letting off the gas w/o putting the clutch in - these conditions would really make the vibration/hum apparent. Certain speeds would really exaccerbate the vibration as well (oddly, 40mph must have been a perfect harmonic balance point, because the truck would settle right down and there'd be no vibration or hum).

Anyway, the rearmost U-joints were pretty sloppy. I'm not sure if this is stock on every Runner, but I have a double cardan joint (w/ 2 u-joints) on the pumpkin side. I replaced both of those with a pair of greaseless/solid Neapco Bruteforce U-joints and now exactly that much is right in the world.

I did a little bit of research, and you can certainly spend a LOT of money on u-joints, but these were close by and relatively inexpensive - ~$45 for the pair.

Voila, riding smooth again (as smooth as one would expect on 35" Grapplers) and pretty cheap, too.

 

[Gurubreed]

you did the double cardan yourself....