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Is it possible to wirelessly shift a 4l80e?

blakes

Red Skull Member
Joined
May 19, 2020
Member Number
205
Messages
242
Loc
Storm Mountain CO
I have HP Tuner on my 2005 8.1l/4L80E (that is really in a 75 GMC C35). Using HP Tuner I can send a command via my laptop to make the thing stay in first gear while I'm descending the mountain with a 22' GN on it. Pretty handy since I'm using a stock 3 speed column shift and cannot hit 1st gear with the shifter (yes I've done all the mods to the shifter and the mount). Not good cause I have to use my laptop to shift it.

Anyone know if there is a wireless/blue tooth option out there that I can use to command shift a 4L80E via an app on my phone?

Edit: all I'm doing is going down a 6 mile very steep dirt road and want to shift it manually to D, then use my phone to make it stay in 1st gear. I can do this via laptop already and it's pretty handy, but inconvenient.
 
I use a stock 3spd column in my crew cab 89. I can manually hit all gears.

I had to extend the shift linkage slightly (1"ish) and cut and weld the pivot arm at the trans about 15* forwards.

I run a fmvb 4l80
 
I have a jakes box on 80 that I just got put back in the shop truck. so far i have first, second and reverse. No third or fourth. I have it narrowed down to the B solenoid is bad or the box is bad. Will try to wire up B externally tomorrow to narrow it down.
 
Bluetooth shift, coupled with muh brain interface control unit.
 
I have installed jake's box on 2 different trucks and it works great BUT it's basically like a manual valve body. I have also seen where you can wire to power one solenoid to have it select that one gear which may be an option. Have a switch on that wire to plug and have it switch on-off-on where on one direction connects the wire like normal and on the other direction turns off computer control to the manual control. I did something similar to a RAD Design shifter for my toyota to manually control it BUT could flip the switch so ECM would control it to turn on the check engine light for emissions.
 
That jakes looks pretty cool.

But really my use case is simple: lock it into first gear when I go down the mountain. Then run full auto until the next trip. I don't take my dually and GN down that often, but when I do, it's a bit hairy because of the 6 mile VERY steep and windy dirt road that I live on .
 
Since you are stuck on holding 1st, grab a couple scotch locks and some wire and a couple 5 terminal relays. the a and b solenoids you will need to control with a ground switch. in 1st the a solenoid is on, b is off. You can wire it up so that you turn the relay on and take control of the solenoids and hold it in 1st. I can draw you the circuit with the relays if you need.

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And I just had a derpy moment, can your scan tool hold it in 1st? I will try it out on a truck here and see(I have a solus pro)
 
Since you are stuck on holding 1st, grab a couple scotch locks and some wire and a couple 5 terminal relays. the a and b solenoids you will need to control with a ground switch. in 1st the a solenoid is on, b is off. You can wire it up so that you turn the relay on and take control of the solenoids and hold it in 1st. I can draw you the circuit with the relays if you need.

I was just about to suggest a relay to control the solenoid with a switch. Having a second switch to power the relay sounds like a good failsafe. Seems a lot easier than trying to control it with your phone.

But forget the scotchlocks - those things are the devil. Do it right so you don't have to fix it later.
 
thanks for all the suggestions guys.

Maybe I will just play with the shfiter linkage a bit more. I'm super, super close to hitting first using the stock column/linkage.

Was thinking there might be a cheap and easy way to rig this thing up with an app on my phone. Doesn't seem like it though.
 
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