strange alarm sound

[LDB]

I have a Sterling 9500. Sometimes, around 1/2 - 2/3 of the time, when I shut down I will hear an alarm. It is very muted. It comes from somewhere in the vicinity of the driver's seat. It sounds for approximately 1 minute. It is 1 second of tone followed by 1 second of silence. It is a mid pitched electronic buzzer sound of some sort. If you don't listen for it you wouldn't necessarily hear it. I can't track it down to a source and my dad could hear it but not locate it either. I am stumped as to what it might be.

 

[layoutshooter]

Strange Leo. My wifes hears a very similar alarm when I shut my truck down. It comes from near the drivers seat. I can't hear it, it falls in the range that my ears no longer work. She says the sound she hears are 4 quick beats just after I shut down. My truck is a Freightliner. I hope someone can't help with this one. Layoutshooter

 

[piper1]

Do you guys both have Eaton Automatic Transmissions?

 

[Refer Hauler]

My 08 Columbia does the same thing, While getting some warranty work done on the DPF it did it and the tech said it was the "Smart Shift" system going through a check mode, I don't know if this correct but I cannot find warning lights or evidence of of a fault. Whatever it doesn't seam to affect anything.

 

[LDB]

Mine is an Eaton autoshift. I don't think it does it every time though. I haven't discerned a pattern to occurrences.

 

[layoutshooter]

Yes, we have a Eaton 10sp Auto-Shift. The beeping is coming from under the seat, at least, my wife says it is. I can't hear it. Layoutshooter

 

[piper1]

My thoughts are it is the transmission getting itself happy (ready) for start up. It could be the process that is running the X and Y shift motors to position for neutral. I've never fully traced the noise but the first time I heard it I was under the cab of an M2 with an autoshift. When you're a big guy like me and you got yourself wadded up into a tight space under a truck and you hear something beeping it tends to get your attention pretty quick!

As mentioned above, do you guys both have the "Smart Stick" or do you have the Eaton push button pads?

 

[LDB]

Not sure of the official name but mine is the big paddle sticking out the right side of the steering column. I'll have to pay attention and see if maybe it's the times I forget to flip the little button to N before turning the engine off in which case my estimate is wrong as that's probably only 10-15% of the time.

 

[Refer Hauler]

Mine is the "Big Paddle" also. I don't hear the beeping all the time and this may be related to hearing loss. But a definate "clunking" is heard when key is switched off.
As stated earlier I cannot find any consequences of the beep.

 

[layoutshooter]

I don't have the paddle, I have the old fashioned Eaton push button. Layoutshooter

 

[jaminjim]

Push button 10 speed, Yuck.

 

[layoutshooter]

Don't like my tranny eh? Thems fightin words!!!!!!! LOL. It does ok for us. we average 10mpg and have got as high as 12. I can live with it. Layoutshooter

 

[jaminjim]

Yeah but, can you really be a trucker without some sort of lever, paddle, stick, or other similar device?

 

[layoutshooter]

I have a clutch pedal. Layoutshooter

 

[davekc]

Sounds to me as well that it is the transmission computer/control module. Some freightliners have a seperate fuse block, but that is behind the drivers seat rather than under it but it doesn't have a buzzer in it.
Not sure on Sterlings, but the 10 speed Eaton may eventually have a recall if not already.
Read it in a industry report but can't remember the source.
It had something to do with the unit sitting too close to the actual transmission and would prematurely fail because of excessive heat. I believe the remedy was either moving it, or putting in some kind of heat shield. There was some other technical data but I can't remember what it was.