Quote:
Originally Posted by clinebarger
Rarely do we see such a well written question!
When you put a 700R4/4L60 in manual 3rd/D3, The Overrun Clutch comes "On" giving engine braking, The Overrun Feed can be blocked, But I don't recommend it as the Overruns help the Forward Sprag stay alive. IF it is falling out of 3rd into 2nd at speeds above 10 MPH upon deceleration...............Your Governor calibration is really wacky 
The Intermediate/Reverse Boost valve boost pressure in Reverse, & Manual D1/D2, A Larger Ratio boost valve will just increase Line Pressure in those 3 Ranges, Does not effect shift timing at all.
We can dive into the hydraulics if you want. But, Your never going to get automatic downshifts at speed with minimum TV Pressure. |
OK, so basically, I just need to look into getting a floor shifter and working the trans manually, right? Will downshifting like this cause other issues? As for engine braking, I like it, so I have no desire to bypass it. I'm not exactly sure what size the current boost valve is, but it does great in D1 and D2, so I see no reason to change it since it only increases line pressure. However, my 2-3 and 3-4 shifts tend to be sluggish and early, and the detent or kickdown at certain speeds seems to be hesitant and/or non-exsistent depending on speed and rpm. It's never seems to want to drop to a low enough gear.
As for the governor, the trans was originally in a 92 C1500 pickup. The valve body was replaced with a rebuilt unit from a Camaro. After first being built, it always wanted to shift way too early, no matter how the TV cable was adjusted. I talked to a guy to get a second opinion. He recommended getting a spring & weight kit and experiment with the governor. I tried a couple different weights that held it too far. I ended up putting the stock weights back on with only a heavier spring change. I don't remember the exact color of the spring. It does shift late under normal driving, but it's only an issue going into 4th as I have to be doing at least 48-50 with almost no throttle.(no TV pressure) I noticed a couple transmission parts dealer sell "Vette" governors setup to operate at 6500 rpm. Would this be a good option?
In some ways, I hate to even mess with anything. I've had it in the truck for about 4 years. It's been driven hard and beat on every time I get in it. I took it to the builder to have it serviced(yes, long overdue.) As the fluid drained, it was clear, first good sign, then he dropped the pan. Absolutely no metal or even clutch material around the magnet. He said, "I must've done something right." I was shocked, seeing that I've not treated it well.