Servo sound when transmission shifts from gear to gear

[WraptorBoy]

Anyone hear a servo type noise when the transmission shifts up and down? It's a very quiet noise but on a quiet road you can hear it. I hear it all the time because I know it's there.

So... shift/servo noise, servo noise stops a couple seconds after shift is complete.

The servo motor sound is definitely in sync with the shifting and seems to come from the front. When the trans has shifted to the next gear, the servo sound continues for a second or two then stops. I hear it when it's shifting up or down. Almost like some motor is activated when the transmission shifts.

It's easier to hear in manual since you can listen for it when you shift it, but manual or auto doesn't matter.

So, on a quiet road, put it in manual and just go real slow then shift up. I can hear some kind of servo motor working when the trans shifts. Then shift again. You should be able to hear it from 1 to 2, 2 to 3 etc up to 6 (could get to a higher gear but going at that slow of a speed won't go beyond 6).

Anyone experience this, hear it or otherwise know what it is?

 

[FordTechOne]

Anyone hear a servo type noise when the transmission shifts up and down? It's a very quiet noise but on a quiet road you can hear it. I hear it all the time because I know it's there.

So... shift/servo noise, servo noise stops a couple seconds after shift is complete.

The servo motor sound is definitely in sync with the shifting and seems to come from the front. When the trans has shifted to the next gear, the servo sound continues for a second or two then stops. I hear it when it's shifting up or down. Almost like some motor is activated when the transmission shifts.

It's easier to hear in manual since you can listen for it when you shift it, but manual or auto doesn't matter.

So, on a quiet road, put it in manual and just go real slow then shift up. I can hear some kind of servo motor working when the trans shifts. Then shift again. You should be able to hear it from 1 to 2, 2 to 3 etc up to 6 (could get to a higher gear but going at that slow of a speed won't go beyond 6).

Anyone experience this, hear it or otherwise know what it is?

There are no servos in the 10R.

As far as a noise...I've don't typically turn my audio system off long enough to notice what you're describing.

When I have turned the audio system off long enough to hear the truck, I have never experienced what you have described.

My best guess is that you're literally hearing the change in transmission fluid pressure/flow as the transmission changes gears...which is completely normal.

 

[WraptorBoy]

There are no servos in the 10R.

As far as a noise...I've don't typically turn my audio system off long enough to notice what you're describing.

When I have turned the audio system off long enough to hear the truck, I have never experienced what you have described.

My best guess is that you're literally hearing the change in transmission fluid pressure/flow as the transmission changes gears...which is completely normal.

That makes sense.

So would this 'change in pressure' be related to a small transmission pump that I am hearing as it operates for each shift?

 

[adllewis42]

I have the exact same noise and, so far as I can tell, it's just a characteristic of the transmission.

 

[WraptorBoy]

I have the exact same noise and, so far as I can tell, it's just a characteristic of the transmission.

Thanks for chiming in with that. Good to know!

What year is yours and how many miles? I'm 2019/3500

 

[FordTechOne]

That makes sense.

So would this 'change in pressure' be related to a small transmission pump that I am hearing as it operates for each shift?

There are 2 transmission pumps; one is the main mechanical pump driven by the torque converter via a chain and the other is an electric pump used to maintain line pressure during stop/start events. The mechanical pump is always turning when the engine is running. You are most likely hearing the solenoids in the solenoid body directing line pressure to the appropriate clutch pack to change the gear ratio.

 

[adllewis42]

Thanks for chiming in with that. Good to know!

What year is yours and how many miles? I'm 2019/3500

2019 - About 12,000 miles. It's made the noise since it was new. I first heard it when I was going slow down a trail at night and I was shifting in manual. Every time I shifted (especially out of first), you could hear the whine. I think it may vary with transmission temp but, either way, I don't let it bother me. Like FordTechOne said, it seems to be a part of the nature of the beast.

 

[invalidusername]

Does it sound like a high pitched meeeeeeeee noise? I only hear that between gear 1-2 and 3

 

[WraptorBoy]

Does it sound like a high pitched meeeeeeeee noise? I only hear that between gear 1-2 and 3

No nothing like that. It's definitely the sound of a servo motor. I noticed it because usually these things are not audible but it sounded a little off, like a worn bearing.

If it was practical and I thought a mic would pick it up, I'd record it. It's fairly subtle until you discover it. Then you never stop hearing it (sorry lol).

As mentioned, it's a motor in sync with shifts. Older transmissions shifted gears when pressure built up etc so newer ones use a motor, or motor assist to move the sleeves. Something to this effect.

In any case, seems normal unless it's not supposed to be heard at all and the servo-type motor is defective (bearing etc).

 

[invalidusername]

This has not posed to be a problem and has been ok. After a while you forget about it. 61k miles