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Discussion Starter · #1 ·
Havent posted in quite a while but its good to finally have a question! alright so I just today got a freshly rebuilt 2004r but without the torque converter, TV cable, anything. im definitely going to run the lock-up as im switching from cast iron powerglide to overdrive purely for the lower rpms, especially on the interstate i take every weekend (and the trip to Bowling Green this year!), but reading the forums, i understand that there is some contention as to whether to have an automatic lock-up in 4th gear, or have a manual switch to control it. or to have the breaks disengage the lockup? and a vacuum switch from the carb to disengage it when the engine is at wide open throttle? so im very confused, and would like to know whats the best way to go about this. I have a factory 283 powerpack, factory 3.36 rear end and gears. I dont race but i like a little giddyup every now and then. Id prefer to not have yet another switch cluttering my dash, but ill do what i have to.
 

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When I had my 700r4 installed, the last thing I wanted was another switch that I had to remember to flip when driving. The shop installed a 12v powered pressure switch in a port on the side of the tranny. When the car shifts into OD and pressure drops, the lock up engages automatically. Nothing extra for my brain or memory to do. I like that.
 

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When I got my car it came with the brake light / cruise control switch wired in which allows the converter to lock up once in 4th but unlocks the converter when you apply the brakes. If the converter didn't unlock when you came to a stop then the engine would stall - similar to not disengaging the clutch when coming to a stop.

It worked fine but my problem is I have 3.08 gears. Great for highway but the engine would lug at street speeds. So I installed a toggle switch which allows me to turn off the power to the cruise control portion of the switch and drive in fourth on the street (under 45 mph). When I get on the freeway I turn on the switch and cruise at over 18 mpg. Similar setup to a couple of the computer controlled add-on systems but less costly.

I thought about adding the vacuum switch to the system but read that the vacuum switches themselves can be temperamental.

Lots off info here and elsewhere online. Comes down to personal preference. IMO.
 

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I've used a GM vacuum switch and had no problems with it disengaging. Unfortunately I don't think you can get one like that anymore at a dealer.

Another way to deal with this problem is to downshift to 3rd gear.
 

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Discussion Starter · #9 ·
So, in my research (googling) ive found that the best, simplest way is to use a botsch relay in conjunction with a 4th gear pressure valve to lockup when in 4th gear and unlock when you press on the brakes! how much does a shop usually charge to swap from powerglide to 2004r anyway? id like to do it myself but the TV cable and all that makes me nervous.
 
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