[Gmecm] Was: Geting rid of electronic transmission.

[Garrett Herning]

Hi Don,

Yes from tests we've done on the force motors, they seem to operate 
correctly over a wide range of frequencies. running the later one at 292.5Hz 
should not be a problem.

Garrett Herning



>From: Don Sauman <donsauman at cythera.net>
>Reply-To: gmecm at diy-efi.org
>To: gmecm at diy-efi.org
>Subject: Re: [Gmecm] Was: Geting rid of electronic transmission.
>Date: Mon, 06 Mar 2006 13:15:58 +0800
>
>Thanks for that Garrett.
>
>We don't see many 4L80Es here in Australia except in private imports 
>although for a brief period GMH brought RHD Suburbans but they have stopped 
>carrying parts even.
>
>Am I reading you correctly to say that feeding the new force motor with the 
>lower frequency will work, or do I need to somehow reprogram to pulse at 
>the higher frequency?
>
>Cheers
>Don
>
>Garrett Herning wrote:
>
>>Hi Don,
>>
>>Where I work we make all kinds of equipt to test transmissions and trans 
>>parts. (Zoom Technology, Inc... anyone in the trans market has probably 
>>heard of us). At any rate, the force motor is nothing more than a pressure 
>>regulator for mainline into the valve body... We have a solenoid tester 
>>and can run either solenoid at multiple frequencies and I've never really 
>>seen any differece in pressure vs current response between 292.5Hz and 614 
>>Hz... all they are doing is PWMing to get an average current to it. All 
>>you want is the PWM frequency to be much higher than the mechanical 
>>response of the solenoid so you don't get it buzzing with the frequency. 
>>Other than that it just sort of regualtes pressure along with the TPS 
>>signal (stomp the gas and it'll jump mainline up... ease off and it pulls 
>>it down)
>>
>>IMHO I don't see any reason the '94 PCM wounld't run the '96 trans just 
>>fine. The cleaning pulse is just a quick twitch every so often to keep the 
>>older force motors from building up dirt and sticking... I guess the new 
>>one was built better so it couldnt do that... having it do that every so 
>>often won't hurt it at all.
>>
>>Hope this helps!
>>
>>Garrett Herning
>>
>>
>>
>>>From: Don Sauman <donsauman at cythera.net>
>>>Reply-To: gmecm at diy-efi.org
>>>To: gmecm at diy-efi.org
>>>Subject: [Gmecm] Was: Geting rid of electronic transmission.
>>>Date: Mon, 06 Mar 2006 12:01:49 +0800
>>>
>>>I have been following all of this with some interest.
>>>
>>>In the spirit of efi and I guess PCMs, I will probably need to reprogram 
>>>an OBD-I PCM (Don't really want to deal with OBD-II if I can avoid it) to 
>>>deal with the changed force motor in the 4L80-E autotrans. Previously it 
>>>operated at 292.5 Hz level but in 1994 was changed to 614 Hz level.
>>>
>>>I have a 1996 trans, and a pre-1994 PCM is being sent to me.
>>>
>>>Can someone who is knowledgeable explain how the force motor works 
>>>(perhaps it is solenoid PWM?) and how the PCM may need to be altered to 
>>>suit the upgraded force motor. Going back to an earlier force motor is 
>>>not an option is not an option as the torque signal feed passage is no 
>>>longer drilled.
>>>
>>>Also, according to the ATSG Manual, with the new design force motor, the 
>>>need for the cleaning cycle is eliminated, so the force motor is no 
>>>longer pulsed every 10 seconds by the PCM/TCM.
>>>
>>>The new force motor (8684216) is applicable to 1994- up 4L80-E, 4L60-E, 
>>>and 4T80-E transmissions.
>>>
>>>Cheers
>>>Don
>>>
>>>--
>>>Don Sauman
>>>35 Asteroid Way
>>>Carlisle 6101
>>>Western Australia
>>>
>>>P: 08 9361 0337
>>>F: 08 9361 0581
>>>M: 0427 389 547 CDMA
>>>M: 0413 746 695 GSM
>>>
>>>
>>>
>>>_______________________________________________
>>>Gmecm mailing list
>>>Gmecm at diy-efi.org
>>>http://lists.diy-efi.org/mailman/listinfo/gmecm
>>
>>
>>
>>_______________________________________________
>>Gmecm mailing list
>>Gmecm at diy-efi.org
>>http://lists.diy-efi.org/mailman/listinfo/gmecm
>>
>
>--
>Don Sauman
>35 Asteroid Way
>Carlisle 6101
>Western Australia
>
>P: 08 9361 0337
>F: 08 9361 0581
>M: 0427 389 547 CDMA
>M: 0413 746 695 GSM
>
>
>
>_______________________________________________
>Gmecm mailing list
>Gmecm at diy-efi.org
>http://lists.diy-efi.org/mailman/listinfo/gmecm