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700R4 prob question

After consulting just 1local tranny shop, was advised against the pressure check because for 1:) Itll cost a hundred bucks to do and 2:) based on my description of the problem, the tranny is spraying fluid because pressure inside is getting too high when it downshifts into 2nd gear and fluid has to go somewhere to alleviate the pressure so it chooses the path of least resistance. Said he had the same problem with an old transmission even after tearing it apart and rebuilding the packs. I do plan on getting a second opinion but, does this seem plausible? Possibly a non worry due to only occurring under extenuating circumstances. Also because I still have yet to get it to the point to spray again. Even on the highway
 
So let's see.....I had a local transmission shop do a "free diagnostic" and the tech told me that the torque convertor lock out is not releasing because there is no signal being sent to it and that it is causing the trans to overheat. But for 1200buks he'll do a complete rebuild trans and TC. Now for that kinda dough, i might look into a new set up altogether.
Any input from the professionals here?:dunno:
 
Some shops will always recommend a full rebuild. Maybe it's because they don't know how to do anything else, maybe it's just how they make the coin. Did you locate the breather tube yet? Did you verify that it's clear? With a running, shifting tranny, I would try a lot of things before tearing it out. For $100, you could buy your own pressure gauge, or install a temp sensor and gauge - just two examples that come to mind.
 
Ok I had the same exact problem. Was driving down the highway bee bopping along about 75 when big puff of smoke and burning smell pulled over and shut the engine down and it looked as if the fluid was pouring out the front of the pan. Week later replaced pan gasket and filter and fluid....tranny was dry since it dumped it all.

Started truck and did it at idle. Would just dump fluid out. Pulled tranny and found the front seal that goes in tranny pump and seals to TC was half way out. I had just installed a new one when I replaced the engine months before and everything worked fine. But hadn't driven it hard.

To the point.....What I didn't do was check the TV cable!!! I have a feeling my pressure got to high and weakest spot was the front seal. Tranny's out for rebuild and found other stuff wrong anyways. But frictions were all still good.
 
Blue85 said:
Some shops will always recommend a full rebuild. Maybe it's because they don't know how to do anything else, maybe it's just how they make the coin. Did you locate the breather tube yet? Did you verify that it's clear? With a running, shifting tranny, I would try a lot of things before tearing it out. For $100, you could buy your own pressure gauge, or install a temp sensor and gauge - just two examples that come to mind.
Click to expand...


Yes I did check the breather tube and it appears to be clear. However it is just a nub on top of tranny so am considering connecting a hose to run up under hood for breathing JIC.
 
So, after researching some other threads I have questions regarding the TCC lock up switch under the dash. I have 2 switches, one is electric and the other appears to be vacuum operated. Vacuum operated switch is for TCC lock up and the electric is brake lights....correct?

Now, how does the system work? When at rest, the brake pedal arm presses against the switch thereby signaling the lock up to activate at higher speeds to prevent slippage with tc? Is this when the 12v signal is present? Or, is the signal supposed to be sent when pedal is pushed and no contact is being made at the switch?

Vacuum line should run to inside firewall? and connect to what exactly?...or should it T and split to somewhere else? Should there be a wire that runs from switch to TCC to send 12v signal to trigger lock up? Does the signal actually get sent to TC or to tranny?

What's best way to test and replace if necessary? Any links or info is super appreciated.

YOU are Awesome!
 
After poking around underneath the dash and fiddlin with the switches I realized that the vacuum operated switch (button) wasn't being completely depressed while the brake pedal arm was up against it so I pushed it into the bracket fully until it was completely pressed in. I replaced a cracked and worn vacuum line under the hood and took it out on the highway to see if the adjustments made any difference.

1st thing I noticed was the shift from 2nd to 3rd was so light and smooth it is almost undetectable. 2nd thing I noticed was that when shifting from 3rd into 4th, it just opens up and rpms drop way down, as if shifting from 3rd to 5th, almost to the point it feels as though a downshift is needed but no threat of a stall. Never experienced this before At this point I could hardly even hear the motor running, so doing the tap on brakes TCC lock up test was a little tricky.

I noticed nothing when just slightly tapping on brake pedal but would notice an audible rise in rpm if i pressed it a lil' more, and engine tone changes almost like a downshift. Even really getting into throttle wouldn't immediately trigger a downshift, and never once experienced the ATF spray this time.
Hmmmmmm, I wonder if maybe one of my issues if fixed? Need to get out on a good hour long drive to really heat it up to test it again...will do today. Fingers crossed!
p.s. I also noticed that a previous problem I've had with the parking brake light coming on at 36mph and staying on until turning off ignition, was not happening now either....I several times had gotten up to 60 or 65 pretty effortlessly, and the light did not turn on or flicker once.
 
There was another post here about the brake light coming on at 36 mph,I donr recall which one though...or what it was that sets it off...:doah:
 
I've read posts about the brake light problem and most point to an issue with the ABS controller i believe. Most decided to just unplug the system. That issue i experience regularly but didn't at all after making these changes yesterday.
 
What vacuum line did you replace I have similar problem with rough shit at times
 
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