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Old 03-08-2001, 04:46 PM
purple73 purple73 is offline
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I know nothing about transmissions. I have a 727 automatic in my Cuda. The car often sits for several days before being started or moved. When I start it up and let it idle in Park for a minute or so, then put it in reverse to back up, the engine revs a little before the transmission begins to take hold and move the car. It is not a slamming type hesitation. It is like fluid pressure has not built up enough and it takes a few seconds before the transmission fully engages. Do I have something going out in my transmission or is this normal?
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Old 03-08-2001, 08:35 PM
MoJoe MoJoe is offline
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If you have no other shifting problems, try putting it in neutral for a few seconds before shifting it into gear. The pump in these trannys doesn't pump any pressure while in park. If this doesn't help, I'd say it's time for a rebuild.

Same thing goes when you're checking the fluid level. Warm it up, run the shifter thru all the gears, then leave it in neutral while you check the level.
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Old 03-08-2001, 09:04 PM
ben440brown ben440brown is offline
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You are almost right, MoJoe. The pump is pumping anytime the engine is running, BUT in park, there is no converter charge pressure. What happens is, the converter drains back into the sump overnight, usually due to normal wear in the pump bushing. When you start it in park, the converter does not refill until you shift it into another position. That's why the fluid checks high in Park -- too much fluid in the trans, not enough in the converter --but checks properly in Neutral. This annoying problem STILL exists -- the late Ram pickups, Jeeps, etc. have a checkball in a fitting in one of the cooler lines to prevent drainback. Unfortunately, this is normal for any unit with milage. Only bad side effect is when the lever (or tower) seal leaks -- then overnight,a a puddle forms under your car because the converter drains back and fills the sump up to and over that seal. During the day, when the car had been driven, the fluid level in the sump isn't that high, so it doesn't leak. The tower seal can be changed without dropping the trans pan.

Good luck, but don't worry about it.

Ben
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Old 03-08-2001, 09:22 PM
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ehostler ehostler is offline
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That sounds like she has morning sickness. The seals ae begining to dry up and are not holding low pressure. I had a tranny in my '68 Charger do that to me and that is what I was told by several friends and the guys at the tranny shop.

Myself, I ignored it for about a year. That's when one of my cooling lines ruptured (it had been rubbing against the back of the block) and shelled out the tranny.
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Old 03-09-2001, 03:37 PM
Chargerchuck Chargerchuck is offline
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I have a 727 & a similar situation- in the morning when I first put the car in drive the engine will rev to it's stall speed (stock converter so about 1400rpm) before it starts to move and then it goes smoothly. That's the only time it does that. I figure as long as it goes o.k the rest of the day and it isn't slipping btw shifts then I'm going to drive it until it starts to give me problems then I'll get it rebuilt.
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Old 03-09-2001, 08:49 PM
reygus reygus is offline
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Agree with ChargerChuck and the others. My 1977 A-727, if not run for a few days, needs to be "primed" with the engine running. I'll slowly go through all the forward gears, back to neutral, into reverse, and back to drive. By the time I start the second trip through the gear selector, the shifts have tightened up. Normal wear and tear, but it shifts good and strong under throttle. My 96 RAM does the same thing at startup, but it still needs a shift kit. My 70 Fury was the last one to be rebuilt and doesn't exhibit this loose, initial shifting after being idle for awhile.
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Old 03-16-2001, 11:22 AM
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tsteiner61 tsteiner61 is offline
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Definitely morning sickness. I recently bought a shift kit and the tech information included with the kit described the problems you are having and claimed to be the fix. The catch...valve body modifications needed to install the kit (substantial drilling of holes in the valve body and filing). The kit is basically a new manual valve that prevents fluid drainback to the pan so the converter is always charged. The kit was from Mr. Shift who claims to have worked for TransGo in his literature, so my guess is that the TransGo shift kit might be similar. I plan to install the kit, but I am going to the pick and pull first to get a backup valve body in case I screw it up, which I inevitably will. Hope this helps.
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