Higher RPMs

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Mr Clean

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He told me to check to make sure I have power to the plug on the trans, so I run a new wire to see if that works. he said if it don't work, just disconnect the wire, so it stop trying to lock up, he sad it won't hurt it to drive it with out the lock up.
 

HotRodPC

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He told me to check to make sure I have power to the plug on the trans, so I run a new wire to see if that works. he said if it don't work, just disconnect the wire, so it stop trying to lock up, he sad it won't hurt it to drive it with out the lock up.

Probably won't hurt it if it's been converted to the 1 wire set up I'll assume. But the older 700r4's can be hurt if they don't have lock up. I'm curious what you're lock up runs off of this wire? I only know of either vac controlled with the switch on the firewall, or ECM computer controlled lock up. :shrug: Hopefully I learn something from this. Do keep in mind though, your trans will run hotter wo the lock up. But, if you're getting what feels like 4 shifts, you're getting lock up.
 

bucket

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Probably won't hurt it if it's been converted to the 1 wire set up I'll assume. But the older 700r4's can be hurt if they don't have lock up. I'm curious what you're lock up runs off of this wire? I only know of either vac controlled with the switch on the firewall, or ECM computer controlled lock up. :shrug: Hopefully I learn something from this. Do keep in mind though, your trans will run hotter wo the lock up. But, if you're getting what feels like 4 shifts, you're getting lock up.

Based on what I know, I wouldn't trust a tranny guy that says it's OK to continue driving a 700r4 without lockup.

As for the one-wire thing. I remember when the overdrive swaps were beginning to get popular, there was some kit for the 700r4 that only needed a power source. It worked off of some pressure switch that was installed in the tranny. All the kits I've seen lately have used a vacuum switch or a sensor that went inline of the speedo cable.
 

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Based on what I know, I wouldn't trust a tranny guy that says it's OK to continue driving a 700r4 without lockup.

As for the one-wire thing. I remember when the overdrive swaps were beginning to get popular, there was some kit for the 700r4 that only needed a power source. It worked off of some pressure switch that was installed in the tranny. All the kits I've seen lately have used a vacuum switch or a sensor that went inline of the speedo cable.

It is true, on the older 700r4's, or should I say, the first ones that came out, if you didn't have lock up connected, you'd burn it up. But GM quickly fixed that issue cuz of transmissions going bad for just a minor problem that caused the lock up to quick working. Even a bad brake light switch would cause the trans to fry. I am not really up the whole lock up thing to know which ones will fry and which ones won't but I know the early ones did for sure. I do also know for a fact, there are many that will NOT be hurt if they won't lock up.
 

bucket

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It is true, on the older 700r4's, or should I say, the first ones that came out, if you didn't have lock up connected, you'd burn it up. But GM quickly fixed that issue cuz of transmissions going bad for just a minor problem that caused the lock up to quick working. Even a bad brake light switch would cause the trans to fry. I am not really up the whole lock up thing to know which ones will fry and which ones won't but I know the early ones did for sure. I do also know for a fact, there are many that will NOT be hurt if they won't lock up.

My '88 Burb killed it's tranny because the lock-up didn't work, or at least it shortened the life drastically. That's when it was still stock too. Now that it's lifted and has bigger tires, it will overheat the tranny in no time flat, if the convertor stays unlocked on the highway.

Now if it's kept in 3rd gear, it should be just fine to drive it that way shouldn't it?
 

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So because all Th350s,th400s, and powerglides are going to burn up? I mean after all, they don't have lockups. Not locking a converter will not cause you to burn up a trans. Cycling a tcc too lifter will though.
 

bucket

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So because all Th350s,th400s, and powerglides are going to burn up? I mean after all, they don't have lockups. Not locking a converter will not cause you to burn up a trans. Cycling a tcc too lifter will though.

That's apples to oranges. Running in OD without lockup is very different from running in D with no lockup. Running in D makes for more engine RPM and less slippage (less heat). Running OD with no lockup would be about like running a th350 with a high stall convertor, you better have a big tranny cooler. For some reason, the 700r4 just seems to get hot a little easier too, no matter how you are driving.

Running a 700r4 or 2004r in OD with no lockup WILL get it hot. Heat kills trannys.
 

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Did you ever get to cruising speed and see if it was lockin up? You should be able to tell by either keepin your foot on the gas and barely touchin the brake pedal or even when you let off the gas lockup will disengage.

Did your tranny guy say anything about checkin the TV cable?

He might be right and the 4th servo might be leaking. Those lips seals tear easily if you install the servos wrong....
 

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We'll have to wait for Mr Clean to get back in town to get an update about this. He works away from home alot. I'm curious to what it came to also.
 

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