update
Even with all her "personality" traits, it's great to have Dora back on the road. It's been 3 weeks and I had gotten used to driving the car so when I finally took Dora around the block I felt tall. I'm sure that will wear off quickly. The
is also glad to have a car back when I'm at work.
With straps, a jack and some grunt the drivetrain is all back together. Here's the new crossmember installed. I'll probably tie into this when I make a new skid plate.
With fluids filled I started on mounting the control box for the tranny. I wanted it easy to reach but out of the way if possible. I first came up with mounting it on the shifter housing so I sat in the rig and test fit it. Thought I came up with a decent location so I spent and hour and made this bracket that I was going to attach it to.
I sat in the seat again for more testing and just found that it wasn't going to work. I like the location but my leg wanted that space more so I moved the box to the console. It's mostly out of the way but very easy to reach.
So this is the control box. There is and indicator to show which gear you are in, a switch to engage the lock up on the t.converter, and the knob which shifts the tranny. It's pretty simple and I understand how it's working.
With two shift solenoids (A, B) in the tranny there are four possible combinations:
- A-on, B-off
- A-off, B-off
- A-off, B-on
- A-on, B-on
That is what the knob is doing, it's combining the solenoids and that changes the gears. I don't have the manual in front of me so I don't remember which combo gets which gear. The t.converter lock up I understand because that's how I was controlling it before, on a switch. What isn't controlled in this setup is the line pressure. That's what I spent time researching and debating; how to control that. I've come up with needing to reduce line pressure when the tranny is cold and once the fluid is warm enough the system can handle full line pressure. I plan on using a simple temperature switch made for immersing that has a trigger point of 115-120F (changed from previous posts). It will be normally closed meaning anytime below that trigger point the contacts will be closed passing current through it to run the force motor (reduce line pressure). Once the tranny warms up and triggers the switch it will open the contact and stop feeding the force motor. The tranny will then default to full line pressure. The hiccup is that I couldn't find a temp switch locally and will have to order one. With it being Christmas week I wasn't going to get this until next week anyways so I ended up wiring the force motor to my previous t.converter lock up switch on the shifter housing. I leave it on until I see 120F on my tranny temp gauge and then switch it off. Once I get an immersible temp switch here I'll drop the tranny pan, weld on a bung and then wire it up. I want that automated so that I don't have to start a driving check list every time I need to go somewhere.
With the control box mounted I got to the wiring. On the left is the tranny harness, the middle is the data cable/connecting line, and the right is a relay. I got all of this when I bought the new tranny and this is what I needed to figure out how it was being controlled. I got out my tranny manual and figured out what was going where and what it was doing. I labeled everything so I knew how to put it back together since the guy cut it out to remove it from his truck.
This is mostly from the relay but I cleaned up the wiring, shorten leads, and replaced his electrical tape with heat shrink.
There is a power wire that feeds the relay, the tranny harness (power goes straight to the tranny, doesn't go through the relay meaning it isn't switched), and the force motor switch. The solenoids in the tranny get fed from this power wire and then the knob sends them to ground to activate them so the other three wires connected to the relay are to ground. There is a ground wire that grounds the relay (which grounds the shift solenoids) and then the lock up solenoid is grounded before the relay. I believe it's done this way because the lock up solenoid is on a switch and not on that knob. All I did after cleaning it up was to reconnect the way it was. I put the relay in the bottom of the shifter housing.
With those connections made I went underneath and connected to the tranny harness. There is plenty of extra data cable that I decided to just zip tie in case I want to move the control box somewhere else and need the extra line for routing. I fastened it out of the way and covered the connections with shielding.
So you probably want to know if it worked. Well... after the engine finally warmed up and stopped stuttering (hasn't been started for 3 weeks and it's been cold) the first spin around the block ended with me parking it and running to the store for some more tranny fluid. I ended up being 4 quarts shy so what I had on hand just wasn't enough. After adding the fluid the tranny came to life. These are my impressions with very little seat time. Shifts are fast, in fact they felt faster than my previous setup. Downshifting is smoother but doesn't offer the engine braking like the old setup did. The tranny seems to run warmer but I was giving it some fuel and driving around town, not on the hwy. It seems to accelerate a little better but then again it's been 3 weeks since it last ran. With some more seat time I'll see how the details work out but overall I think it was a success and it WORKS!
One issue that bugs me was that the indicator on the control box isn't working. I thought maybe it was bad but it flickered along with another LED on the same power line so I'm going to check that connection thinking maybe it loosen when I moved the shifter housing when bolting it up. Also I can see that the knob could be harder to handle with gloves or slippery fingers so I'll probably look into getting something more like a lever.
If the control box location works out where it is I'll re-enforce the mount and paint the box to match the theme.
There is some speculation about dually rears and if yours is the CnC version you are really set.
Holy hell, talk about beefy! I've never seen one out from under a truck up close so I guess I never had a good idea for how HD they are. Sweet!
