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Any thoughts as to why my tranny feels like it is trying to shift at highway speeds while in Drive. Does not do it in Overdrive. It is a 700R4 with a vacuum line from the carb to a switch which has a wire and plug that goes to the tranny. Could the switch be bad or making a bad contact? Any thoughts. Here is a link showing the switch.
http://rides.webshots.com/photo/2516403700098853003mxxnyd?vhost=rides

That's a switch for the lockup torque converter clutch. It's wired in series with a pressure switch on the valve body that needs a particular governor pressure to complete the solenoid circuit and put the converter into lockup. High vacuum+correct governor pressure=lockup. Slow down, or step on the gas, and the converter clutch unlocks. It should work in both direct and OD if the right conditions are met. There are four modes: 3rd. gear unlocked, 3rd. gear locked, 4th. gear locked and unlocked. If it locks up too soon and shifts up and down too much, install a higher pressure governor switch. The pressure roughly corresponds to MPH- - - -45 lb. switch=45 MPH, etc.
Jerry

Hey Jon, Your TV cable is incorrectly adjusted. That adjustment is the key to making a 700R4 behave correctly. Don't keep driving it like that, you "will" Smoke the transmission. Check out Bowtie Overdrives. Their website has lots of info on these transmissions.
The wire that plugs in to the tranny is for the lockup converter.
What carb are you running? That could be part of your problem.
some carbs wont work correctly with a 700R4 unless they have the correct brackets & cable set up. Bowtie overdrives makes & sells kits to properly set the TV cable up to most of the popular carburetors.

Hotrod, I have a 650 Edlebrock carb. Are you talking about a higher pressure switch, the switch that the vacuum hose connects to. At least I think that is what you are referring to. Also, can you get these at any parts store?
Jeffl, is the TV adjustment something I can attempt or would it be best to take to a auto mechanic. It may be out of adjustment, but I'm not sure which way it should be adjusted, in or out. Sorry for sounding so dumb, but this is an area that I have not dealt with in the past. Any suggestions.

Jeffl, is the TV adjustment something I can attempt or would it be best to take to a auto mechanic. It may be out of adjustment, but I'm not sure which way it should be adjusted, in or out. Sorry for sounding so dumb, but this is an area that I have not dealt with in the past. Any suggestions.

No, the pressure switch I'm talking about is inside the transmission, in the governor pressure passage on the valve body. The vacuum switch simply applies voltage to the connector on the transmission at high-vacuum cruise, and disconnects it when you step on the gas and lower the vacuum. Once inside, the voltage has to go through the pressure switch to energize the lockup solenoid. Both vacuum and road speed have to be right to allow the converter clutch to lock in. Since the governor pressure increases as speed goes up, installing a higher-pressure switch keeps the converter from locking in too soon and causing a condition called "chuggle" where the converter clutch engages and disengages repeatedly due to a mismatch between speed and throttle opening.

Edit: The TV cable adjustment is very critical on a 700R4/RL-60 (same transmission, different name). In general, pulling the cable away from the transmission housing delays the shift, allowing RPM to increase before the shift happens. Shift too soon, and clutches slip and burn. Too late, and you get violent gear engagement and possible driveline and/or rear end damage. On a non-original installation, the cable adjustment has to be a seat-of-the-pants situation to get the smoothest shift without slip or harshness.

Jerry

Sounds a little over my head. Guess I should take it to someone who has experience in inserting pressure switches and can make the necessary TV cable adjustments.

jon, when I put the 700R4 in my pickup (replaced a 350) it took me a good 30 minutes of stopping and starting to get it where I wanted it.
I would think your cable goes through an "eye" that has a screw that you screw in to lock the cable. If so, then take your allen wrench or screw driver with you and find you a nice stretch of road. If its not "holding in gear" long enough then loosen the set screw and pull the cable out about 1/8", tighten it and then take off and go through the gears again like you normally drive. If its still not right the repeat the procedure again. .....if you are shifting to fast then go the other way. Do it until you "feel" it is changing where it should be or where you want it.
You can do it.

I might just throw this in as MY experience. When I put the 700R4 in my pickup I also put a shift kit in it. BAD DECISION. The first gear in these tranny's is plenty, so is second and so on. With the shift kit its a chore to keep the tires from spinning the first time or two that it shifts. Depending on just how much I'm on the gas. I reallly have to "light foot it" to keep it from snatching my head off...... I will take it back out.
Just MY opinion.

First unplug the connector to the lockup at the trans. Drive it this way & see if the problem goes away. If so then you know it is in the lockup instead of shifting back & forth between 3rd & 4th. Besides the correct cable adjustment the arc of the throttle lever is important also. There is a bracket available for the Edel. carb for that. One of the performance trans. co. explanes it on the internet but I'm not sure which one. I ran across it on a search. The connection for the cable should be 1 1/8 in. from the center of the throttle shaft. It starts about 1/3 of the arc in front of the verticle center line & goes 2/3 behind.
PS I like the wheels I got from you. George

Bowtie overdrives makes & sells a kit to adapt an edelbrock carb to a 700R4.
face_head/111http://www.tvmadeez.com/

What it is doing is while in Drive, at highway speed, say about 55 to 60, it feels like it is shifting, then stops, then trys shifting again, and so on. It shifts okay, just does what I said after I am up and running at highway speed. I have not noticed this in Overdrive. Do you think I need to loosen and pull the cable out about 1/8" and keep trying that.
Wrenchbender, happy you were satisfied with the wheels. Would you try pulling the electrical plug in the tranny that comes from the vacuum switch before adjusting the TV cable? I am attaching a photo of the throttle cable and TV cable. I assume you are talking ablout adjusting the bottom cable, the TV cable. I noticed that the plunger is all the way out. Should that only be out half way? Photo of Cable:
http://rides.webshots.com/photo/2249546780098853003adSxMM?vhost=rides

Thanks for all the help everyone. I need to figure all this out so I can drive it. right.

Just unplug the electrical connector at the vacuum switch. That will disable the lockup clutch, and you can work on getting the 1-2-3-4 shift right with the TV cable adjustment. THEN you can deal with the lockup clutch, strictly from a vacuum/governor pressure standpoint.
Jerry

OK Jerry, thanks. I will try it when the weather clears.

The place to start with the cable is with the throttle wide open the cable should be pulled all the way out. You shouldn't have to tailor it much from there.

Wrenchbender, I will try that. Did you get to go to the swap meet?

Finally got the shifting to work. I played with the TV cable and got it close. Took it to a transmission friend of mine and he eliminated the vacuum/electrical line to the tranny by doing some kind of wiring. He said that is the best way and it eliminates the vacuum switch. Thanks for everyones help.

Yes. Con & I set up a booth. I sold quite a bit of stuff. George