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4L80E gear question

Trucker2k16

Well-Known Member
Messages
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Location
Charleston south Carolina
Hey guys i have a '91 4l80e on a tci ez tcu behind a fuel injection 383 stroker my question is i noticed in park at idle it says 1st gear and when the truck not running and key on it says 2nd shouldn't it say park/netural?
 
I believe the 91 has a string attached to the shifter lever thingabob around the steer column. If You look at it from underneath the steer column there should be a clip shoved onto that bell affair thingabob and that clip should have a string attached. Moving that clip so that the indicator points to park with the shift lever in park, should fixum indicator error.
Or, it could be that the 91 has an electronical indicator down on tje transmission shifting mechanism that might be faulty or need adjusting.
I’m just not that familiar with the 4L80E in the 91s. I do know that the 700r4 in the older units like that was string controlled indicator.
 
I believe the 91 has a string attached to the shifter lever thingabob around the steer column. If You look at it from underneath the steer column there should be a clip shoved onto that bell affair thingabob and that clip should have a string attached. Moving that clip so that the indicator points to park with the shift lever in park, should fixum indicator error.
Or, it could be that the 91 has an electronical indicator down on tje transmission shifting mechanism that might be faulty or need adjusting.
I’m just not that familiar with the 4L80E in the 91s. I do know that the 700r4 in the older units like that was string controlled indicator.
No not that my controller screen say 1st in park at idle and 2nd not running the pointer is fine
 
The gear display in the tci most likely reads the pressure manifold switch assembly for actual gear it's in. With no fluid pressure the switches will send back a signal for 2nd which is also hydraulic limp mode.

On another note, I hope you changed out the EPC solenoid to a 94-03 style, opened the EPC vent port in the valve body, and blocked the line pressure accumulator port. Most don't know this, but 91-93 used a different pressure control system than 94+, you have to do more than just change the internal harness if you want a 91-93 to live with a 94+ style controller.
 
The gear display in the tci most likely reads the pressure manifold switch assembly for actual gear it's in. With no fluid pressure the switches will send back a signal for 2nd which is also hydraulic limp mode.

On another note, I hope you changed out the EPC solenoid to a 94-03 style, opened the EPC vent port in the valve body, and blocked the line pressure accumulator port. Most don't know this, but 91-93 used a different pressure control system than 94+, you have to do more than just change the internal harness if you want a 91-93 to live with a 94+ style controller.
That makes sense just as i figured to be normal. Thanks.
 
I know, right! I grew up with a friend like him - dudes are like walking mechanical encyclopedia.
I consider You being one of those types too, aling with several others in this forum.
Seems that when I need to know the know how, do a little searching and digging, its mostly already been discussed, figured out and cured.
All I gotta do is follow the instructions. Thats where the dislexia usually kicks in for Me. 😹😹😹😹
 
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