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TH400 issue

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Old Sep 7, 2007 | 10:11 PM
  #21  
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Old Sep 7, 2007 | 10:35 PM
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Originally Posted by 2armor
Thanks jim, I did put a good brass screen TCI filter at the oem location. It also has a Perma-cool remote filter under the hood with SS braided lines and all AN fittings. When I finished installing the shift kit with new fluid, I also installed a Fram PH8 filter to replace the original Perma-cool filter. This would be the first time its ever had a fram oil filter on the Tranny cooling line. You think this could cause a restriction issue? Perm-cool lists it as an acceptable replacement though..

Governor piston -no. What should I look for? I have heard about the little plastic gear failing but figured since it shifted at 5000rpm the governor was working. I dont know- Not much experience with automatics.. Wish I had a 4 spd in it!
I used a remote fram Ph8 on a tranny for over 150,000 miles with no problems. Must change it at least once a year or it will blow the lines.
Also never had the solenoid connected at all for all those miles. Make sure the solenoid is not stuck.

How many miles on tranny???
Last time your symptoms happened to me, the seals were shot internally and a rebuild was in order.
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Old Sep 7, 2007 | 10:45 PM
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Originally Posted by noonie
I used a remote fram Ph8 on a tranny for over 150,000 miles with no problems. Must change it at least once a year or it will blow the lines.
Also never had the solenoid connected at all for all those miles. Make sure the solenoid is not stuck.

How many miles on tranny???
Last time your symptoms happened to me, the seals were shot internally and a rebuild was in order.
The car has 44k original miles. If it needs a tranny I'm getting a 200R4 but I haven't gave up on it yet. Its just a toy, not daily transportation..

Solenoid is not stuck. It seams to operate properly-
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Old Sep 7, 2007 | 10:58 PM
  #24  
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I'll be bok

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Old Sep 7, 2007 | 11:41 PM
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Make sure your trans vacuum lines are all hooked up/not leaking. I've had my bubba'd vacuum lines pop loose up near the intake manifold and the car acts exactly as you described.
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Old Sep 8, 2007 | 11:30 AM
  #26  
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Originally Posted by 1mpalss
Make sure your trans vacuum lines are all hooked up/not leaking. I've had my bubba'd vacuum lines pop loose up near the intake manifold and the car acts exactly as you described.
Thanks. Manifold, Vacuum lines, and modulator are fine. Its all new- only 6 months old.

I'll pull the valve body today and clean good and start all over again.
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Old Sep 8, 2007 | 06:12 PM
  #27  
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Went and picked up a TH400 manual earlier. Read it and found no
" ah-ha's". I found that I did put the cone filter in the right way and in the right tube the first time. Oh well.

I took it all a part again and cleaned it good. Pulled the governor and it was fine, pulled the modulator again it was fine, good vacuum from the manifold, etc.

Put it all back together, filled it up and took it for a 12 mile loop. Works fine now. Nice snappy shifts. Must have been a piece of dirt is my only guess..

Oh yeah, no one had the detent solenoid in stock so I just used the original one so it wasn't the culprit either.

On the road again....
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Old Sep 8, 2007 | 06:22 PM
  #28  
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After working on my car one day, took it out for a drive and my tranny had all kinds of strange things going on--turned out I unknowingly had bumped the vacuum line off of the intake manifold that goes to the tranny. Once I hooked it back up all was fine. Its worth a look.

Greg
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Old Sep 8, 2007 | 06:28 PM
  #29  
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Originally Posted by greg454
After working on my car one day, took it out for a drive and my tranny had all kinds of strange things going on--turned out I unknowingly had bumped the vacuum line off of the intake manifold that goes to the tranny. Once I hooked it back up all was fine. Its worth a look.

Greg
Yeah, that was the 1st thing I checked since I was tuning and timing it before the tranny issue. I used 3m thread sealer on the brass fitting at the manifold and used 3m wheather strip adhesive to hold the vac line in place on that fitting.

I pulled the line off the modulator while it was running- Had real good suction.. Idunno.
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Old Sep 9, 2007 | 11:43 AM
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Originally Posted by chris75stingray
i've heard you're supposed to use vasoline insted of grease because grease will not melt off and the vasoline will. the grease coulde be clogging something up.
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Old Sep 10, 2007 | 08:57 AM
  #31  
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Originally Posted by weimer20
Yeah that too! I wasn't lazy this time! I went in the house and got the petroleum jelly this time for those ball bearings and gaskets. Maybe that was it. I read in the tranny manual it says to use it too.

The B&M instructions said jelly or grease... Wonder why they would say that?

Anyways- I'M IN THE TIRE CHIRPIN' CLUB now.
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Old Sep 10, 2007 | 10:56 PM
  #32  
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Originally Posted by 2armor
Yeah that too! I wasn't lazy this time! I went in the house and got the petroleum jelly this time for those ball bearings and gaskets. Maybe that was it. I read in the tranny manual it says to use it too.

The B&M instructions said jelly or grease... Wonder why they would say that?

Anyways- I'M IN THE TIRE CHIRPIN' CLUB now.
So you got it fixed? Way to go! Glad to hear you're "up and runnin'".
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Old Sep 11, 2007 | 02:27 AM
  #33  
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I just saw this thread and I was going to suggest a stick valve in the governor. But it sounds like you found the little bugger. If you have similar problems down the road, re-check the governor...make sure that the valve in the governor shaft move freely when you move the flyweights to full extended position [and back]. A scratched or slightly dinged valve can have an intermittant sticking problem and cause "late" shifting. Also make sure that the governor drive gear is in good shape and the retainer pin is tightly installed.
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Old Sep 11, 2007 | 01:57 PM
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Originally Posted by 7T1vette
I just saw this thread and I was going to suggest a stick valve in the governor. But it sounds like you found the little bugger. If you have similar problems down the road, re-check the governor...make sure that the valve in the governor shaft move freely when you move the flyweights to full extended position [and back]. A scratched or slightly dinged valve can have an intermittant sticking problem and cause "late" shifting. Also make sure that the governor drive gear is in good shape and the retainer pin is tightly installed.
Thanks guys! Yes, When I went "back in her" I did evrything more slowly and through. Alot of cleaning along the way too. I pulled the governor and it seemed ok, I did spray the living hell out of it with solvent, air and gave it a good inspection.

I think I'll replace that gov drive gear in the near future. Mine looked original so I'm sure it could go soon. Thats an easy $5 / 30 minute insurance policy too.


Last edited by 2armor; Sep 11, 2007 at 01:59 PM.
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Old Sep 11, 2007 | 06:48 PM
  #35  
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Having a governor failure in a THM400 is NOT a good thing! I think you are wise to replace it while you're in there already.
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Old Sep 12, 2007 | 12:43 PM
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Originally Posted by 7T1vette
Having a governor failure in a THM400 is NOT a good thing! I think you are wise to replace it while you're in there already.
Replaced that plastic gear yesterday. $5.60 for it and took only 15 minutes...

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