3.4L Whining Noise In Gear

[96pearlrunner]

1996 4Runner Automatic Limited. My car is making a whining noise in all the drive gears except Park and Neutral. The whining noise is similiar to a power steering pump when it's low on fluid. It's constantly whining while driving but goes away when you let off the throttle. I just replaced all the drive belts and power steering pump is topped off. Any ideas what it is. I'm assuming it's a transmission problem.

 

[calimobber]

Are you familiar with the sound of belts slipping?

I bet you one of your belts is slipping.

 

[96pearlrunner]

No, I'm not familiar with the sound of a slipping belt. Wouldn't it whine in park and neutral also if it was a slipping belt. In Park and Neutral the car sounds fine. As soon as you throw it in Drive you can hear a humming noise even at a stand still and as you accelerate the whine becomes more noticeable and louder.

 

[95yotarunner619]

I have what sounds like a vacuum leak coming from the transmission. It's kind of like a humming, but I really hear it in reverse

 

[19963.4lsr5]

Check your trans fluid level.

 

[Chrizzouse]

Could be a transmission going bad. I have the same issue on my 99 with 186k. planetary gear failure is common.

 

[Bijan]

Could be a transmission going bad. I have the same issue on my 99 with 186k. planetary gear failure is common.

Exactly what he said

 

[Buckaroo]

The Big Question is does the sound change with the speed of the engine or the speed of the car? I would suggest that a whining noise which changes with the speed of the car when you are accelerating could be the rear differential. Is it coming from the rear? If so, first step, check the rear diff fluid level.....

Buckaroo

 

[Chrizzouse]

The Big Question is does the sound change with the speed of the engine or the speed of the car? I would suggest that a whining noise which changes with the speed of the car when you are accelerating could be the rear differential. Is it coming from the rear? If so, first step, check the rear diff fluid level.....

Buckaroo

Mines coming from the front...:sobbing: Unfortunately

 

[96pearlrunner]

i'll drain everything this weekend and do all fluids again and see what happens from there. the noise is definitely coming from the transmission. shifts fine and drives fine. it sort of sounds like a supercharger.

 

[Chrizzouse]

I just call it my turbo....:becky:

 

[Inoahguy]

The Big Question is does the sound change with the speed of the engine or the speed of the car? I would suggest that a whining noise which changes with the speed of the car when you are accelerating could be the rear differential. Is it coming from the rear? If so, first step, check the rear diff fluid level.....

Buckaroo

Sorry to revive such an old thread, but what if it's neither? Mine is more of a whine under acceleration. Basically the more my foot is in the pedal the more it whines. It's starting to become a "nails on a chalkboard thing" and I just apologize to my 4runner when I have to accelerate harder than the average old timer.

 

[Inoahguy]

i'll drain everything this weekend and do all fluids again and see what happens from there. the noise is definitely coming from the transmission. shifts fine and drives fine. it sort of sounds like a supercharger.

Did you ever figure this out?

 

[amalik]

Did you ever figure this out?

He last logged onto t4r in January of this year, I wouldn't be hopeful for a reply.

 

[spartacus]

Whine from where is it engine or drivetrain Is it only when you accelerate or when in park and rev the motor you can hear the whine?

 

[Inoahguy]

Whine from where is it engine or drivetrain Is it only when you accelerate or when in park and rev the motor you can hear the whine?

its a pretty high pitched whistle/whine only when in gear under moderate acceleration and gets higher pitched with heavier acceleration. For example when I leave my cul de sac if I get 50% into the pedal it will start to whine at the top of the gear. I'm going to start with the AC Compressor Idler Pulley and hope that fixes it.

 

[ER RN]

1996 4Runner Automatic Limited. My car is making a whining noise in all the drive gears except Park and Neutral. The whining noise is similiar to a power steering pump when it's low on fluid. It's constantly whining while driving but goes away when you let off the throttle. I just replaced all the drive belts and power steering pump is topped off. Any ideas what it is. I'm assuming it's a transmission problem.

what about bearings in Alternator, My runner has a whine when accelerating and my mechanic mentioned the alternator.

 

[Buckaroo]

Sorry to revive such an old thread, but what if it's neither? Mine is more of a whine under acceleration. Basically the more my foot is in the pedal the more it whines. It's starting to become a "nails on a chalkboard thing" and I just apologize to my 4runner when I have to accelerate harder than the average old timer.

I think you are saying this is a whine which doesn't change with the speed of the engine or the vehicle but happens under "Drive" condition which changes with torque - no noise under, "Cruise" (enough throttle to maintain speed), "Float" (just enough throttle to keep engine load off drive train when slowing) or "Coast"(no throttle when slowing) conditions. Assuming the noise is coming from the rear diff, it sounds like gear noise, not bearing noise.

I don't have experience with the e-locker so the following suggestions relate to the open diff. If noise is getting worse, I would not delay following up on this as the fix may be getting more extensive (and costly). Would suggest first making sure diff fluid level is good - if low, top it off and see if noise persists. If so, change the fluid making sure you use the right stuff - I have been using Valvoline 80W-90 (#VV831). If noise continues, I think the next step would be to check the diff set-up which is probably a job for a shop that works on diffs regularly. They can check the conditions of the gears, shims, bearing preload and backlash.

Good Luck.

Buckaroo (aka Old Timer)

 

[Jaysen4runner]

Mine was doing the same, low on fluids when I brought it. Top off fluid, drive for a while no longer present.

 

[Wrencher93]

I have a similar issue. I drive a 2001 SR5 and it has started to make a mild whining noise which correlates with engine rpm. It gets louder until about 2200 rpm and then engine noise drowns it out. Makes this sound in P,N,R, and D although there seems to be a slight change in sound if the runner is in R or D as opposed to P or N. I recently did a timing belt job and replaced the water pump, both idler pulleys, and the tensioner while I was in there. I've also recently replaced the transmission fluid, all three drive belts, and the alternator. After reading threads on here I'm beginning to think it is transmission related but I'm still kinda lost.