Mechanics

LOUD VIBRATION HUM NOISE A

2001 Toyota 4Runner

Noises problem
2001 Toyota 4Runner 6 cyl Two Wheel Drive Automatic 81,000 miles

Hello,
my 4runner makes a loud 'vibration' hum type of noise - but only once it reaches 60 mph and above. Would appreciate any clues as to what it may be. I did have ujoints replaced 3 months ago - not sure if that's connected? No other engine probs, accelerates fine. Could it need balancing perhaps? Thank you.
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Chef2511
July 5, 2008.



Hi chef2511,

I would suggest giving the U joints another check. How many did you replace?

KHLow2008
Jul 8, 2008.
Hi KHLow2008,

Thanks for your reply. I replaced 4. When you say have the u joints checked, do you mean checked for proper installation? Could that be causing the noise?

Tiny
Chef2511
Jul 10, 2008.
Hi chef2511,

Yes, check if the installations were properly done and if they require any greases.

Check for loose flange nuts too.

KHLow2008
Jul 10, 2008.
I took the car in and mechanic says drive shaft needs balancing - does this sound like something that was caused as a result of the u joints being replaced?

Also, is this critical or can it go if I don't mind the vibration.

Dealer mechanic quoted $175 for parts but said they'd need to keep the car for a few days as it needs to be sent out to a specialty shop.

Thank you!

Tiny
Chef2511
Jul 10, 2008.
Hi chef2511,

If the shaft they are refering to were the ones that the U-joints were replaced, then it could be a poor job done.

I would advise against continuing using them, the unbalanced shafts would cause other areas to go bad, especially the flange bearings/bushes and oil seals, not to mention the mountings.

KHLow2008
Jul 11, 2008.
My 2001 4Runner is doing the exact same thing. Did you resolve the problem. I have never replaced ujoints. What are the symptoms?

Tiny
Plschrader
Jul 15, 2008.
Hi plschrader,

Symptoms of bad U joints.

When accelerating the vehicle seems to vibrate at a certain speed and the vibration reduces as soon as you let go of the pedal. It will resume again when you accelerate again.

Acceleration is not full throttle type, just moderate increase in speed.

KHLow2008
Jul 15, 2008.
Would I notice this vibration at all speeds or just high speed?

Tiny
Plschrader
Jul 15, 2008.
Hi plschrader,

Vibration should start at about 30 mph or higher and at different speed it might vary in rate.

KHLow2008
Jul 15, 2008.
Hello,
Thanks so much for the input & suggestions.
After having it checked - dealer mechanic says that my drive shaft needs balancing. Interesting is that the same dealer serv center replaced both my front and rear drive shaft u joints 3 months ago and now this problem but they insist it's not related. However, they offered balance the drive shaft without charging for labor - parts only - at $175. I don't know how to verify if this is really the case or if they did a poor u-joint job and that somehow caused the drive shaft to go off balance.
I wonder how much $ I'll be saving on the labor alone vs going to a different shop where they will charge for labor. Would appreciate feedback on the approximate labor costs to remove the drive shaft and balance it - approx how long would something like that take? An hour, or more like 4 or 5? Thanks much!

Tiny
Chef2511
Jul 16, 2008.
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