Installing A Electrical Kit In A 4L80E

[bk95td]

I bought the electrical kit mentioned and pictured in this thread:
http://www.thetruckstop.us/forum/showthread.php?29077-Electrical-kits-for-4L80E-s
I finally got to putting it in today:rolleyes5:
The kit is going in a 94 k3500 srw. This truck was throwing a 1-2 shift solenoid code. It wouldn't shift out of low gear. I figured as long as I had to go in there I would replace everything electrical since the truck is 17 years old and it has 150,000 miles on it.
I had removed the front driveshaft when I was testing the wiring to the tranny.I unplugged the main connector then dropped the pan and filter. I got a bit of a surprise when I looked in the bottom of the pan:yikes::yikes: Dark sludge in the bottom. Very little metalic look to it.








The first thing after the pan and filter was removing the electrical connector from the tranny case. There is 4 hooks that need to be pushed down while holding pressure on the inside part of the connector.



Next was the pressure regulator[force motor][drivers's side front of trans]. It is held in with 1- T25 head screw. A little prying with a slotted screwdriver popped it out.



Next is the TCC[torque converter clutch] solenoid It is held in by a retaining clip in a slot of the valve body. A small slotted screwdriver in the slot will pry the retainer out.



I started plugging the new internal wiring harness on as the new component is installed. All the connectors are different so they can't be plugged in the wrong place:thumbsup:
Next was the pressure switch. It's held on to the valve body with 8mm head bolts. As each component is removed tranny fluid comes out so the drain pan has to stay under while all the work is being done.






The shift solenoids were next. They are not the same and will only work in the correct spot[dummy proof]:thumbsup: Each one is held in with one t25 head screw







Next i put the wiring harness in the retaining clip to hold it in place then smeared some atf on the o-ring of the main connector and slid it in the tranny case.
Installed new filter seal and filter. Pan back on and fill with fluid.







I had to clean the truck end of the main connector because the old tranny connector leaked atf into it. 3 or 4 rinses with wd40 and blow out with air hose got rid of the red atf bleeding out of the connector.

Tools used: large medium and small slotted screwdrivers[to pry solenoids and main connector out],channelock pliers to pull the tcc solenoid out, 1/4" ratchet with T25 bit for solenoid hold dwn screws, 1/4" wobble extension and 10 mm socket for pan bolts, 8mm socket for pressure switch bolts, ball peen hammer to drive new filter seal in. I used a 3/8" ratchet and extension w/10mm socket for all but the rear pan bolts, a trouble light to see and lots of lint free shop towels.

 

[ak diesel driver]

did it help?

 

[bk95td]

did it help?

I don't know yet. It's up on the stands yet and is getting new oil cooler lines before it comes down. i'm optimistic that it will work[fingers crossed] With the sludge in the pan, I'm thinking of disconnecting the tranny cooler and pumping the dirty fluid out of the converter before driving. The fluid had been changed at least once because it didn't have the reuseable GM gasket on it. The truck had sat unused for 5 or 6 years before I bought it.

 

[JiFaire]

Nice job, Barry... thanks for sharing and taking pics!

Jim

 

[WarWagon]

Looks normal for the silver dark colored stuff on the bottom of the pan. Least my transmission looked like then when I did a 25K fluid change.

 

[Burning oil]

My 2 cents:
On the back of the main bulkhead connector If reusing it. Clean it real good with brake cleaner the apply a good coating of black RTV. I do it on new connectors also. Its very common for the pins to seep ATF otherwise.

 

[bk95td]

My 2 cents:
On the back of the main bulkhead connector If reusing it. Clean it real good with brake cleaner the apply a good coating of black RTV. I do it on new connectors also. Its very common for the pins to seep ATF otherwise.

This is all new. I did think about using something extra to seal the wires but didn't. The old main connector was weeping badly. Most i've seen weep or leak.
I started it up today with the top cooler line connected to a drain pan. I pumped about a gallon of fluid out of it untill it came out light pink. The old fluid was dark red.
It does go forward and reverse:thumbsup::thumbsup: Not shure yet about the rest of the shifting.:skep:

 

[handcannon]

Thank you Barry.

Great pics. This will be very helpful for me since I need to do something about my TC control.

Leroy-- are you talking about the connector end that is inside the tranny?

Don

 

[bk95td]

Leroy's talking about sealing the inside, side of the big gray connector with the green o-ring. There is some type of seal to prevent oil from weeping into the outside of that connector. They almost always fail and fill the cavity between the truck and tranny connector. The tranny fluid can actually wick up the truck wiring harness inside the wire insulation.

 

[Burning oil]

Yep, on the inside where the wires go into the connector.

 

[handcannon]

Thanks Barry and Leroy. I thought that was where you meant, but I needed to be sure.

Don

 

[Chief915]

Any news on the shifting yet?

 

[bk95td]

Any news on the shifting yet?

I hopefully will know later today. I just have to put new trailer wiring in yet before it comes down.

 

[bk95td]

:shiiiiiite::shiiiiiite::mad2: Still no shifting. Have to hook up scantech again and check all sensor outputs[mostly input and output speeds]
On the bright side ,the electrical connector doesn't leak and the fluid and filter are changed.:thumbsup:

 

[bk95td]

Update

I finally got to figuring out why no shift today. It was throwing codes 81 and 83. I checked the wires from the tranny to the ecm and all were good:???:
:mad2::mad2: Then checked the fuse that powers the transmission. The old solenoids must have blown it. New fuse and all is well. It works just like it is supposed to:thumbsup::thumbsup: It is throwing another code but it doesn't effect the tranny at all.

 

[buddy]

Hey thanks for all the pics and write up, much appreciated, even if it really only needed a fuse! Although, now it will go another 150,000 without any shifting issues.

 

[bk95td]

I had checked the fuses before i bought the kit and may have replaced it even.:???: It apparently blew it again. I hadn't checked it after I did the kit install.:twak: One of the old solenoids must be shorted. Positive comes off the fuse and the ecm supplies ground and senses when solenoids are energized.
The old internal harness did come in handy to check for power and ground.:thumbsup:

 

[deejaaa]

this is going to be my next job. throwing codes like Santa on Christmas.

 

[dka99burb]

Great writeup. It helped me install my kit a few days ago.
One trick that may be obvious for a lot of you but it took us a bit to think of was when we were trying to depress the 4 hooks to pull the old bulkhead plug out they were difficult to depress all at the same time. We found a socket that fit over all the hooks, 1-1/4" I think, and that made it a lot easier. Just a tip that I hope helps someone...