"Rebuilt" 700r4 issues

Discussion in 'Automatic Transmission' started by Obwonkonobe, May 12, 2018.

  1. Obwonkonobe

    Obwonkonobe Full Access Member

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    Starting to think the same thing.. He's supposed to drop off my Speedo gears and pickup his core soon, I think Il have some questions for him
     
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  2. Splandman

    Splandman Full Access Member

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    I have had a ridiculous amount of trouble with my 700r4, a few of them actually. There is a really long thread on here somewhere about it. Whatever you do, I would not take it back to the builder you used. My problems finally got straightened out because I got it to someone who actually knew what they were doing. I had a few problems but the main ones were related to TV cable and improper lockup. If your builder did away with the wiring, maybe he set it up to lock up off pressure. I am no transmission expert, so maybe HotRod can say, but if it's set to lock up off pressure, and your TV cable isn't correct, then the pressure isn't correct, so lockup won't be right.

    Now I am running a setup from Bowtie Overdrives for the TV cable. A B&M SuperCooler, and my lockup is set up the way it should have been. The trans is handling my almost 450 HP and 33 inch tires with no issues.

    https://www.amazon.com/gp/product/B000CIGE9Q/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
     
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  3. Obwonkonobe

    Obwonkonobe Full Access Member

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    @Splandman I've never heard of "lock up off" pressure. I know that in 4th the pump dosent supply much pressure, but I'm unfarmilliar with any modifications to change those characteristics. Can any one explain it a little more?
     
  4. Splandman

    Splandman Full Access Member

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    I'm sure one of the other guys can. My builder set mine to lock up off pressure and it was not working correctly. I only found this out when I was under the truck and saw the electrical plug dangling. When I saw your comment that your builder got rid of the wiring, I wondered if he didn't also set yours up that way.
     
  5. Obwonkonobe

    Obwonkonobe Full Access Member

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    Can you define "lock up off pressure"?
     
  6. Splandman

    Splandman Full Access Member

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    As I said, I'm not an expert, but here is an explanation from another forum:

    I am running the "hydraulic lockup" in one of my 700R4 and am happy with it. I also have a Ron Francis computer in another 700R4 and my Bud is running a Painless kit in his that I installed for him. While no expert, I think I have a fair grasp of the How, Why and Whens of the 700R4. The "hydraulic lockup" works off the pump pressure and is so simple and fool proof. The kit is a steel ball and a set of colored springs to choose from. I just happen to select the mid range spring and it seems to work fine for my set up. As you accelerate the motor, the pump pressure builds and overcomes the spring pressure, allowing the hydraulic fluid to redirect into the lockup valving to lock the converter. As you decelerate the motor, and wheel speed allows the pump pressure to decrease, the spring overcomes the reduced pressure and the torque converter unlocks. I have never experienced any failure to unlock and I have experienced lock up in other gears, under heavy acceleration, but you would never notice this if you were not really looking for it to do so. It is not a malfunction and no unusual wear and tear will occur.



    Unlike the guy that wrote this answer, I experienced all kinds of trouble. Mine was locking up way too early, it locked up in all gears but 1st, and also was coming in and out of lockup constantly while in 4th. At one point I thought I had a bad converter. A lot of my issue may have been the improper TV cable bracket, it's hard for me to say because I got the new bracket and changed the way may converter locked up at the same time. I only know it works great now.​
     
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  7. Obwonkonobe

    Obwonkonobe Full Access Member

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    @Splandman great explanation thank you! So its basically a mechanical lock up, I like the sound of it
     
  8. 84 M1008

    84 M1008 Member

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    Guys like me that have a 6.2 and 4.56 gears appreciate that 400rpm drop.
     
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