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4l80e / controller questions

The other problem you would have is most speed sensors with only 2 wires won't read at slow speeds, so definately stick with a 91-93 style setu if you can with your double underdrive setup. Otherwise the TCM wouldn't even see you moving until you were up to 3rd gear or so. It looks like you finding an early model was actually a blessing for your particuliar swap.
 
Yes it looks that way. It's definitely an earlier model as it still has front and back wiring connectors (not plugs). I also read that the diesel torque convertor is fine with a big block. Still debating if I should have it rebuilt. I would hate to have it go out in the middle of BFE and have to rely on a random shop to rebuild it. I'll pull the pan and post some pictures one of these days.
 
Pull the rear speed sensor out of it, and look inside to make sure there is a tone wheel for it to read. ONLY the 91-93 4X4 transmissions had a tone wheel for the output shaft, but they all had a spot for a sensor there(starting in 94 they put in a dummy plug that looked like a speed sensor, but was just a plastic dummy plug).
 
I will, but it still has the wires on it so I'm not worried. Also I bought it with a NP205 attached which was only available in 1991.

Is it a bad idea to test the solenoids with jumper wires directly to a car battery? Would I hear them click with the pan off.
 
You can power them via 12 volts, but not for long(2 seconds tops). Without them being immersed in fluid, they can get hot, and if it's a PWM solenoid it can easily burn up. And yes, you should hear them click. I wouldn't power the big one though as I believe the PCS solenoid is only 5 volts, and 12 could instantly pop it.
 
THEFERMANATOR said:
You can power them via 12 volts, but not for long(2 seconds tops). Without them being immersed in fluid, they can get hot, and if it's a PWM solenoid it can easily burn up. And yes, you should hear them click. I wouldn't power the big one though as I believe the PCS solenoid is only 5 volts, and 12 could instantly pop it.
Click to expand...

Great info. You must be a technician. I'm probably going to have to change the PCS solenoid out anyway so it will be new.

Burning oil said:
OK, as soon as I hear back from them I'll let you know.
Click to expand...

Excellent.
 
Yes they can. Sorry to hear that and hope you recover fully.

In other news I did verify that my trans has the rear tone ring. :)

But it doesn't have a MLPS (or the bosses to mount one:banghead:) so I need to figure out a way to hook up a neutral safety switch and the reverse lights. I could easily fab up some brackets off the pan bolts to mount a MLPS, but will my '91 gear selector shaft fit it? :(
 
For trucks 94 and older, GM used a switch mounted on the steering column for the nuetral safety and reverse lights. It wasn't until 95 that GM used a NSBU on the trans for the gear display, nuetral safety, and reverse lights. A few have put a modern NSBU switch at the trans, but it requires swapping the shift shaft out, and going with a shift cable instead of mechanical shift linkage.
 
So sorry I thought I had replied to you in an email, but it was Nate.

I can sell Quick4 for $725 shipped in USA. That's the controller, wire harness and shipping.
 
THEFERMANATOR said:
For trucks 94 and older, GM used a switch mounted on the steering column for the nuetral safety and reverse lights. It wasn't until 95 that GM used a NSBU on the trans for the gear display, nuetral safety, and reverse lights. A few have put a modern NSBU switch at the trans, but it requires swapping the shift shaft out, and going with a shift cable instead of mechanical shift linkage.
Click to expand...

I looked into swapping the shaft out and that looks easy. I was already planning on a cable shifter, either modding my 727 shifter or buying a Winters.
 
I feel sorry for you. Following the advice and info will result in YOU ON YOUR BACK pulling the trans out Multiple times, a large sum of cash, and still a broken trans/TCM//Truck. The mis-info is just flat out wrong. I would never do 90% of this. No one on this site has enough knowledge to help in this application. It is to bad that some can't learn from others who have been there many times and solved many others problems.
1st the 91-93 units have a controlled force motor routine or cleaning cycle to allow correct function of the FM. The FM is cycled to the low pres/Hi Pres and there is hardware, a big heavy spring in the VB to compensate for this cleaning cycle. You can elect any aftermarket TCM BUT I have only seen one with the smarts inside there's to control the Bosch FM (91-93) It a Mega squirt. I am surprised these experts didn't even read the post on this and look at their web site. When I read thier TCM info, the TCM wasn't oreleased BUT did have the function for the Bosch FM. I would Never just swap the FM. Danger of very Hi pres that can break the case.
On the other hand an Expert stated you can use a 94 up unit and run the 91-93 TCM. In this combination, the TCM will run the FM cleaning cycle and the compensator pressure spring is not there to compensate for the LOW PRES cycle. This can cause a clutch to slip. NOT IN MINE.
I get a good laugh most of the time reading this. On the other hand, it is sad to see such posts with opinions that will cause you money and a failure. Maybe it will last a while, it's all yours. It's really ashamed that others can't learn when someone offers to teach them.
But I am no expert.
 
wilber said:
I feel sorry for you. Following the advice and info will result in YOU ON YOUR BACK pulling the trans out Multiple times, a large sum of cash, and still a broken trans/TCM//Truck. The mis-info is just flat out wrong. I would never do 90% of this. No one on this site has enough knowledge to help in this application. It is to bad that some can't learn from others who have been there many times and solved many others problems.
1st the 91-93 units have a controlled force motor routine or cleaning cycle to allow correct function of the FM. The FM is cycled to the low pres/Hi Pres and there is hardware, a big heavy spring in the VB to compensate for this cleaning cycle. You can elect any aftermarket TCM BUT I have only seen one with the smarts inside there's to control the Bosch FM (91-93) It a Mega squirt. I am surprised these experts didn't even read the post on this and look at their web site. When I read thier TCM info, the TCM wasn't oreleased BUT did have the function for the Bosch FM. I would Never just swap the FM. Danger of very Hi pres that can break the case.
On the other hand an Expert stated you can use a 94 up unit and run the 91-93 TCM. In this combination, the TCM will run the FM cleaning cycle and the compensator pressure spring is not there to compensate for the LOW PRES cycle. This can cause a clutch to slip. NOT IN MINE.
I get a good laugh most of the time reading this. On the other hand, it is sad to see such posts with opinions that will cause you money and a failure. Maybe it will last a while, it's all yours. It's really ashamed that others can't learn when someone offers to teach them.
But I am no expert.
Click to expand...
There IS people out there running the new style force motor in 91-93 trucks with no problems. I was leary at 1st as well, but it has proven to work. The early style 91-93 PCS required a cleaning cycle because of the frequency it was modulated at, and was done to prevent clutch buildup inside the force motor. The compensator spring and such was used to dampen the pressure control and slow the pressure control so when the FM went full stroke the pressure wouldn't spike to either side. Others have put pressure gauges on there 91-93 trans and seen a pressure fluctuation during the cleaning cycle and freaked out thinking something was wrong. And to use a 91-93 trans in a newer truck involves swapping out to a newer style force motor, and if you want to be real picky you can plug off the compensator damper circuit. You may not agree with it, but it DOES work and has been PROVEN to work. The aftermarket controller companies have decided not to support the 91-93 force motor, and instead tells you to swap out to the new style and call it a day.
 
Some trans remover and installers and maybe a small rebuild qualify as an Expert. One trans is not test. Maybe you know more than the personal at GM Transmission Engineering? Rebuilders make experts I guess. I quit here and see an ego problem and will never return. I would like to help but I understand now why there is little in the way of posts, questions, and activity on this site..... You're the looser here. Free help and advise that will work. I'm not giving my time.
Bye
 
Can we keep this civil. All the aftermarket manuals I have read that mention the force motor do say to swap it out for the later version. The mega/micro squirt doesn't work with multiple low ranges so that's not an option. Wilber do you have a reference or first hand experience?
 
Wilber, my 2cents not intended offend but to help: your input is always useable. If you say white and someone else says black, it is up to the person who owns the truck to figure out who to follow.

Theferminator's opinion is listen to a lot here because he has proven to be right almost every time he gives it. He has been a tranny guy for more than a day or two. I appreciate his help because he is always here to give it.
That doesn't mean I don't want to hear a different point of view. To me the more info the better, the. I can learn more.

Maybe a person doesn't want to follow his advise and would follow yours, but if your not here to have the debate with Ferminator to prove your point then the guys who need the help can only hear one opinion, right? After reading 2 or 3 differing opinions, a novice can then so more research on their own and figure out what is the best thing to do for them.

When I was adding the turbo to my truck I had to overcome signal for the engine speed to my TCM problem. Buying a controller was not in my economic capacity of the time. No one person had the cheap fix to my problem of the time, but using advice from a couple of different people and s little of my own creativity it gone done very well, and low cost. Stay around to help where you can, learn where you can, and make friends that you can agree with on SOME things.

Idk who has the better answer you or Ferminator because idk trans, but if he stays and you never help in the future it will sure look like you ran away from embarrassment...

Ferminator, I know I can't hurt your feelings cuz your level of skills and mine are obvious to those who read you catching my errors. :wacky:
 
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