I would like the torque converter to stay locked up while I am using the exhaust brake, but still drop it out of overdrive if I choose to.
If I use the brake light switch, and I want to use the brakes and the exhaust brake simultaneously, that would unlock the converter and reduce the effectiveness of the exhaust brake. So that pressure switch would probably be the way to go. Once I get the truck down to 40 miles an hour or so, the exhaust brake probably isn't needed.
This truck is always very heavily loaded, with a big camper in the bed and/or my race trailer behind. So I actually prefer a mostly manual control so I can use my senses and my brain too make decisions rather than rely on an inflexible automatic device.
If you are using a stock 47 and hauling all the weight using a Jake - you should consider some of the devices out there’s to crank throttle pressure/line pressure up.
Closed throttle will drop line to 60 +/- and using the Jake with a lot of weight can take it’s toll on the clutch’s.
Transman, I talked the guy who built the trans today. He said the pressure has been increased, but he didn't know offhand how much. What do think would be a minimum pressure during deceleration using the exhaust brake? He mentioned putting a solenoid that somehow operated the cable to increase pressure when using the exhaust brake. That must be the devise you speak of. Where would I hook up a pressure gauge to test it? Thanks, Joel
Use the line pressure tap to monitor, passenger side of main case, center tap.
By increasing pressure I assume he means line pressure by adjusting the Allen head screw on the valve body.
But that won’t help you at closed throttle on the Jake hauling all that weight.
He is correct, adding a solenoid or driver motor to move the throttle pressure cable lever all the way back when using the Jake is the direction you want to take.
The later 48RE transmissions have a TTVA on them to accomplish this very thing for the same reason.
Also the Jake is much more effective when the lockup converter is on.
