47RH 2-3 shift slip any ideas?

Trans is back in, line pressure is running about 175-180 now. Still getting the same pressure drop when I hit lockup. But its does ramp back up to 175 as the rpms come up over 2000. Lockup is still fairly soft, was hoping it would be harder. All the shifts are mild really, 2-3 locked is much better than before though.

Can the 47 pump just not keep up with lockup fluid demand at low rpm or what? Or is my converter screwed internally? The pump is brand new. All the seals in the trans are new, everything was gone through including the Vb.
 
Also when I had the valve body out months ago I drilled the lockup plate hole to like .125, no difference in lockup firmness.
 
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Did you grind the 3 Land valve with a 45* angle halfway through the middle land? That quickens the torque converter lockup as well.
 
YOUNG GUNS15 said:
Did you grind the 3 Land valve with a 45* angle halfway through the middle land? That quickens the torque converter lockup as well.
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We didn't do anything to the valve body other than drill that hole out. It's a goerend built vb btw. It holds the power fine, just doesn't shift and lockup near as hard as my friends suncoast trans. I suppose it's easier on parts though lol.


Sent from my iPhone 4s
 
12vCumminsFTW said:
Yeah, thats what I figured. If I can figure out this pressure drop deal it should be good to go.
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That TQ converter has a piston to fill for the apply clutch (lockup). That's your pressure drop. It will not go away (completely). Just a part of the operation.
 
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raychem said:
That TQ converter has a piston to fill for the apply clutch (lockup). That's your pressure drop. It will not go away (completely). Just a part of the operation.
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Yes, I understand there will be some drop, I just thought it should recover more than it does. The pressure does come back up, its just takes more rpms vs unlocked. I'm probably just paranoid. Anyway, we are going to put a gauge on another truck with a built suncoast and see how the pressure acts in comparison.

Kinda sucks that we couldn't get the 48 stuff to work out this go-around, I will definitely be upgrading to the 48 pump when I pull the engine out next.
 
YOUNG GUNS15 said:
Did you grind the 3 Land valve with a 45* angle halfway through the middle land? That quickens the torque converter lockup as well.
Click to expand...

Where's this at? I'm dropping my pan this week to change oil, filter and gov. I want to check if any work was done.
 
[ame="http://www.youtube.com/watch?v=qTaLlN4CGdU"]0-100 - YouTube[/ame]

Quick run through the gears with the TC locked. Shifts ok I guess, 3rd seems to hesitate just a bit, almost seems like a very slight bind up.
 
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Those of you with line pressure gauges, how much does line drop when you hit lockup? I am still getting almost 50 psi drop in lower rpms, it does come back up as the rpms come up but never fully recovers. It runs 155-170ish max in OD LOCKED, when I unlock it jumps up to like 175-180.
 
12vCumminsFTW said:
Those of you with line pressure gauges, how much does line drop when you hit lockup? I am still getting almost 50 psi drop in lower rpms, it does come back up as the rpms come up but never fully recovers. It runs 155-170ish max in OD LOCKED, when I unlock it jumps up to like 175-180.
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no more input? The trans guy didn't think it was anything to worry about. Just seems like you would want max pressure in OD locked. But I guess the tc lockup steals a lot of volume.

Also another slightly odd thing, 3rd gear has a delay, when I hit the shifter it takes a second or so. Not sure if it has something to do with the full manual vb and tv lever tied or what? Its always done it since day 1. Shifts fine just takes a bit, kinda annoying when going fast n stuff. Have to think ahead a bitLOL
 
kinda a new issue, got a weird whining moaning sound from the trans area/rear of engine. gets louder as the rpms rise, won't do it in park only when driving. wtf?
 
mathews8pt said:
Sounds like it could be a pressure leak in the vb
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the whining sound or pressure drop? or both?

The pressure drop is even worse in this hot weather, with hot fluid TC locked I barely see 165ish psi and thats at 2500+ rpm. Unlocked the pressure ramps up to 175+ quick even at low rpms.
 
Well since the engine is out I'm going to be putting a 48re pump in. I also either need to send out the converter to get it rebuilt or get a new one, as I don't trust it.

Is it possible there's something leaking by in the converter? I see another member is having the same lockup drop issue.

BTW the weird whining noise might have been the cam and/or gear walking around, as the gear walked off like 1/2" and was rubbing the cover:doh: Funny that it made noise only under load though.
 
yep, i'm having the same issue, its always been a bit of a drop, that recovers right away. now Ive got a huge drop and it barely gets over 160psi at about 2500rpm I was going to ask if you found any torn seals when you took it apart
 
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