Things i did for ACC/HCU install that helped or would have.
1. You got to wash the area your working in. Pop the hood and wash around the HCU etc.( If you get any grit in your ACC/brake lines your fcked).
Pop the hood looking at the truck from the front, on the right side of the fan shroud , theres the HCU wash it.
2. Pick up caps for the lines, so you dont get grit on the threads, and it also stops fluid from coming out while your working on it.
This is what I used. The red caps work for the 4 lines on top, The Blue caps work for the other 2 lines coming out the side.
I took a picture of how much fluid I lost swapping the ACC/HCU over.
Pull a line put a cap on it, keep moving.( also as your pulling lines and putting caps on, take the red plugs you removed earlier and put them in the HCU your pulling out.
(Its going to help later).
3.If your donor HCU has Red caps covering the holes, you need to remove or loosen before you install.
They are hard enough to remove when not installed, but really hard if you wait till you get it onto the truck.
My Suggestion: Remove all the Red caps before installing HCU, just put a small piece of tape over each port,(which will be easy to remove as you do each line).
Or loose a extra 1/2 hour by not doing it, leaning over the engine bay. Your Choice.
After I changed out my HCU/ACC you can see in the picture how little fluid actually got lost.
4. If you have never worked on these type of break lines, you could get in a lot of trouble cross threading.
Im 65 years old and what I found always works is to:
put the line over the hole your going to put it into.
If it feels like you have to pull or push it over the whole, then you need to take that pressure off before trying to start the treads.
Now is the part that will make this so easy: Wiggle the line back and forth a few millimeters as you are trying to start the treads.
Do this with your fingers no wrenches,, as you wiggle it and turn it by hand you will be able to get the treads started really easily.
Because you are trying to thread it by using just your finger force, you wont be able to cross thread the line, plus as you wiggle it back and forth ever so slightly it will find the treaded hole so much easier.
5. My biggest worry and reason I did not do sooner, was I thought accessibility for removing HCU was going to be a *****.
Once you pop the hood and wash the old HCU, you will see how easy it is to work on.
Th 3 mounting bolts I believe are 13MM , 2 can be reached easily from drivers wheel well. other from underneath.
The 6 lines going to the HCU and the electrical connector are best accessed ( for me anyway) from the top of the motor.( I used a small ladder to stand on when possible).
6. Remember to undo the Red clip on the harness before pulling on the white lever. ( I let it hang when I was working, as the are was nice and clean so I felt it was fine, just putting it slightly out of the way. If I had a zip tie it would have helped.
7. I pulled the HCU out of the top of the motor where I was working, its going to be hard to wiggle around the wires and everything.(But your going to be glad you put the Red plugs back in the old HCU, cause you wont have brake fluid everywhere.
Sorry for the long write up, but after reading and re-reading the 60 pages, I did not find a lot of helpful information to help with what I have posted.
Anyway took less than a couple hours taking my time swapping out the old to new HCU.
The programming of the New ACC system and bleeding breaks was a bit of a **** show.
But reading the install guide, and the other guide on installing a Used HCU and it all worked.
Love the Stop and Go.
Thanks to all those that made these mods possible. Jimmy etc.