responses are in Italics.
YOU SAY:
The force motor AKA PCS that controls the line pressure changed from 93 to 94. It went from a 292.5HZ(cycles per second) to a 614HZ(cycles per second) and eliminated the cleaning cycle every 10 seconds that was used on the previous 91-93 force motor.
91-93 was a BOSCH manufactured FM. 94-03 was a Holley manufactured FM 04-end production @ GM was Borg-Warner manufactured.
Who cares who made it, the FACT is IT CHANGED FREQUENCYS and eliminated a required cleaning cycle every 10 seconds that it required. The 94+ did not use said cleaning cycle due to the different cycles per second the 94+ used(also GM made the change to the same FM that the 4L60E/4T80E used).
YOU SAY:
Also a new spacer plate was used for 94 and the torque signal compensator valve in the accumualtor housing was eliminated.
The spacer plate change @ the FM was due to the 3 circuits being changed from the Bosch (1991-1993) FM to the Holley (1994-2003) FM. They were not to be interchanged within one another. You shouldn't have a 91-93 valvebody/spacer plate and install a Holley FM. The set MUST remain together: FM, Valve body, Spacer Plate, and Controls (TCM). In some swap cases with a given VB changing to another FM you can end up with very high/uncontrolled line pressure.
So which is it, are all the valve bodies the same or are they different from 91-93 to 94+ as far as controls go. I wil ladmit I was mistaken and it was the FM that changed, not the TCC. But in your first post you say there is no different valve body. So which is it?
YOU SAY:
In order to use the older style force motor and accumualtor housing you have to swap valave bodies I have been told(have not tried this myself to verify it, but many have done this swap and had issues until they either changed PROM's or valve bodies). One can use the new style trans and force motor with a PROM update to eliminate the cleaning cycle and change the force motor cycles per second.
A PROM UPDATE???? How can a PROM change a routine embedded within the TCM? This is where the FM cycling software is contained. What is a NEW Style TRANS? You mean a 94 forward I take it. A PROM CHANGE WILL NOT ELIMINATE ANY Cleaning cycle of the FM.
You obviously have NO idea what a PROM is. PROM stands for programmeable read only memory(or EEPROM starting in 95 and fully implemented in 96 is electronically eraseable programmeable read only memory). The PROM or EEPROM is what tells any controlelr what to do. ALL controllers wether it is a ECM/TCM/PCM/BCM WHATEVER type of controller from any era use a PROM or EEPROM to tell it what to do and for the algorythims it follows for it's controls. So yes the PROM can tell it to flash out morse code with how it controls the FM, or whatever it is programmed to do. And the "NEW STYLE TRANS" simply refers to a 94+(I guess I thought wrong in ASSUming one could figure this out). So YES a PROM change CAN and HAS eliminated the cleaning cycle of the FM.
YOU SAY:
If one uses a new style trans with an old PROM the force motor will likely live a short life at the different HZ, and you will have a pressure spike every 10 seconds when it commands a cleaning cycle.
The FM running at the different HZ will NOT have ANY reduced life in either HZ. The cycling of the FM runs it to each end of the duty cycle. The Accum compensates for the pressure loss/gain for a few milliseconds this occurs.
I didn't say it would, but most likely shorten it's life. Others HAVE tried this in the tuning by running the solenoid at a higher duty cycle and it normally resulted in a burned out coil in the solenoid(ask somebody with a 6 speed ALLISON what happens if you set the TCC duty cycle up to 96% instead of the stock max of 60%). So the duty cycle/cycles per second, HZ, or frequency CAN have a bearing on solenoid life. If a solenoid is meant to be run at 250 cycles per second for a max duty cycle, running at double the cycles per second could in fact burn the coil out. And if you use a 94+ accumualtor WITHOUT the torque compensating circuit(you know the exra circuit you admitted was in 91-93 valve bodies for the 91-93 FM) in a 91-93 truck with stock programming, you will get pressure jumps when it commands the cleaning cycle every 10 seconds as the required extra circuit isn't there to dampen it.
YOU SAY:
And if it happens to shift during said cleaning cycle you could get one funky shift with the pressure fluctuation.
How do you know this will occur? The software will not allow the routine during an upshift nor a downshift event. Shift Pressure (up or down) has a higher placement than the cleaning routine within the pressure routine operation. And if it happens during a shift????? What is "ONE FUNKY SHIFT"?
For the unimagainative a "funky shift" would be one that happens when the pressure spikes because you are running a trans without the required extra circuits that you yourself admits are there in 91-93 valve bodies that are not present in 94+ trannies. In a perfect world the controller wouldn't do a cleanign cycle during a shift, but say it begins a cleaning cycle and a split second later the conditions are met for a shift. Do you think the controller is going to not shift, or is it going to shift? And if it shifts duirng a pressure spike(because of that pesky missing fluid circuit) don't you think a pressure of 300 when it wants 125 could be a cause for a harsh or violent shift. Or say it does in fact delay the shift most would call that abnormal or "funky".
YOU SAY:
ON EDIT(in case somebody in the future references this thread) The valve body difference comes into play if you put a 94+ trans into a 93- truck you either have to use the 91-93 valve body, OR open up the 94+ valve body and drill out the seperator plate as well as swap force motors to make it work. So yes there is a difference, but it is in the seperator plate and passages drilled or not drilled. Otherwise you have to use the new style PROM that eliminates the cleaning pulse every 10 seconds.
Well sir you do not understand what has to be placed within a package to make it function. Each package is like this:
For the Force Motor package you should keep these items as a package and together: The FM, Valve body, spacer plate, Controls or TCM/PROM. The Bosch FM is a 91-93 and is SILVER in color. The Holley FM is 94-2003 and is Black in color. The Borg-Warner is 2004 until the end 08 for GM and is black. The Borg FM has a different connector.
And some of us have had to "make it work", and found that though it may not be "factory approved", it CAN work.
The 91-93 vs the 94-2003 FM Circuits can be viewed in the service manual hydraulic layouts. If you lay each of the 3 FM hydraulic circuits out you can see how replacing OR SWAPPING one with another WILL NOT WORK and will give you uncontrolled/high line pressure in ONE CASE. No PROM change can eliminate any of the embedded routines or add any as the cleaning cycle of the FM.
Ok now you back saying the PROM doesn't control it, but the TCM does control the cleaning cycle. You know as I put above, the PROM TELLS the TCM what to do, so the PROM controls said cleaning cycle and those embedded routines. And others HAVE interchanged and drilled the neccesary holes to make it work. I don't have the instructions anymore because I don't mess with 4L80E anymore, but peopel HAVE interchanged the FM's.
YES you CAN have a 2006 model trans with a 1994 TCM or PCM and it will run correctly. OR said like this: You can use a Holley TCM or PCM control to operate a Borg-Warner FM. I personally would suggest to increase the pressures somewhat or exactly 10 to 15 PTS (Pressure Torque Signal) to compensate for the ODD operation of the Borg-Warner FM. The Borg-Warner FM will give you a given pressure when NEW and it will DECREASE over aprox 5 to10k miles by the said 10 PTS amount. If the PCM has Adapts or SHIFT ADAPTS it will compensate for the loss. It is the nature of the beast. So I would add this "commanded" PTS to the calibration. Now PTS is a number from 0 to 90. It has a direct bearing on line pressure. To find what ending line pressure will be in a NON REVERSE gear take the PTS multiply this by 1.4 and add 40. This number will give you a pretty good indication of actual line pressure (but not in Reverse)
And all you are doing here is confirming what I said about a 95+ trans going into a 94+ truck, but you are still not addressing your arguement about using a 94+ trans in a 91-93 truck without addressing the FM problem. I was trying to address the FM problem when using a 94+ trans in a 91-93 truck as it can be done in a few different ways.
Why does the loss occur in the B-W FM? Sediment in the fluid. If you cleaned the FM and retested it, you would be exactly on the mark for pressures. But since sediment lives within the fluid just bump it a bit. No you can't filter this out within reason and it does not need to be replaced.
opcorn: 