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Sluggish Transmission
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Author:  rustyfords [ Sun May 09, 2010 9:54 pm ]
Post subject:  Sluggish Transmission
So I just finished swapping in an engine/transmission combo into my 76 Valiant.

The pair was a bargain and the guy promised them both to be running. He was dead on about the engine....it fires up right away and idles nicely.

The automatic transmission (from a 69 Dodge) on the other hand, I'm not too sure about. During the swap, whatever fluid was left in the transmission drained out through the tailshaft and was then replaced after the swap.

So today, I added 4 quarts of ATF4 and figured I'd just cycle through the gears and see if it moves back and forth. It moves, but I have to rev the engine and then it's only moving a bit.

My knowledge of automatics is pretty poor, so my question is....is this a sign that the thing is toast or could it be something else....say....that the torque converter lost it's fluid and needs filling?

I'm hoping there's some hope for the transmission. I still have the transmission that came out of the car originally, but I really don't want to drop and change them if I don't have to.
Author:  Fopar [ Sun May 09, 2010 10:49 pm ]
Post subject: 
You will need a lot more than 4 qts in the transmission, put in 2 more qts.
Then go through the gears on the selector, put transmission in neutral with the motor running at idle, check level add more if needed.
Author:  SlantSixDan [ Sun May 09, 2010 10:55 pm ]
Post subject: 
Did you drain the torque converter? Change the filter? Adjust the bands? Also take a look for external sources of trouble, such as a kinked trans fluid cooler hardline or blockage in the trans fluid cooler located in the lower radiator tank.
Author:  valiant1966 [ Mon May 10, 2010 2:11 am ]
Post subject: 
When I brought my car home a couple of years ago(towed it home), it did the same thing. Checked the tranny fluid and it was a bit low, not a lot though. I added some and it sprung back to life. I think these slant six trannys are real sensitive about having the fluid level correct.

Warm the engine up thoroughly, shift it through the gears, put it back in Park and check the transmission fluid level. Fill it to the correct level. DO NOT overfill it, that can destroy it too.

Good luck
Author:  rustyfords [ Mon May 10, 2010 6:36 am ]
Post subject: 
Thanks for the replies fellas. (Two big reasons I like this forum...1) you guys actually know what you're talking about 2) no childish drama and name calling when someone asks a simple question)

I'll be taking another look at it today. I don't know the transmission's history as far as how much fluid was drained from it before I got it, but there couldn't have been much left in it when we installed it, because it was placed at a pretty steep angle during installation with no yoke/plug in it.

I did notice that the pan gasket is leaking now that it has some fluid in it, so I may have to drop the pan to get that cured, or I may be lucky and simply have a loose bolt.

I'll take yall's advice and add some more fluid, check all my lines, etc the next time I get a few hours with the car. (This working for a living always cuts into my car time)
Author:  SlantSixDan [ Mon May 10, 2010 9:11 am ]
Post subject: 
Quote:
I did notice that the pan gasket is leaking now that it has some fluid in it, so I may have to drop the pan to get that cured, or I may be lucky and simply have a loose bolt.
Okeh, so that sounds like a filter change was not done. You'll definitely want to do that. Discard the floppy cork or rubber pan gasket that comes with the filter kit; they're useless. Instead, from the Chrysler dealer get the really nice double-seal, reusable rigid pan gasket P/N 4295 875AC.
Author:  Doc [ Mon May 10, 2010 10:32 am ]
Post subject: 
Check carefully for the leak's source prior to removing the pan / changing the pan gasket.
Many times ATF will leak from the selector seal or fill tube o-ring, then it runs down & along the pan gasket, making it look like a gasket leak.
DD
Author:  rustyfords [ Mon May 10, 2010 11:46 am ]
Post subject: 
Quote:
Check carefully for the leak's source prior to removing the pan / changing the pan gasket.
Many times ATF will leak from the selector seal or fill tube o-ring, then it runs down & along the pan gasket, making it look like a gasket leak.
DD
That may be the source of the leak. I had to change out the selector when I did the swap.

Sounds like I'm doing a filter change and installing a new seal on the selector as well.

Anyone have a part number on the selector seal?
Author:  rustyfords [ Mon May 10, 2010 12:57 pm ]
Post subject: 
Just so I'm sure that I'm speaking from a point of knowledge....

That transmission is an A904, correct?
Author:  SlantSixDan [ Mon May 10, 2010 3:44 pm ]
Post subject: 
Correct, A904.
Author:  rustyfords [ Wed May 12, 2010 6:11 pm ]
Post subject: 
I went to the Chrysler dealership and bought a rigid transmission pan gasket, which I thought they'd have to order....nope....they had it in stock!

Wow...it is dramatically different from the floppy rubber one that came with the filter.

So...under the car I go this afternoon and wow....it's amazing that the thing was holding any fluid at all. Half of the bolts were loose and the existing gasket was a very low quality cork thing.

A bit of good news....there was no sign of metal bits in the transmission pan and it was relatively clean with a minimal amount of sludge.

I also changed out the selector shaft bushing while I was under there.

So....Mr. Valiant should be tightly sealed in the transmission department. Now to replace some old heater hoses and go ahead and install the new water pump that I have (I'll keep the old one for an emergency backup, since it did appear to be pumping water without leaking)

Then I'll seal it all up for the last time, add real coolant instead of just water and see if it'll take me on it's first run in two decades.

I may have to video it and put it on YouTube for you guys to witness.
Author:  SlantSixDan [ Wed May 12, 2010 6:27 pm ]
Post subject: 
You, ah, did put a new filter in while you had the pan off...yes?
Author:  rustyfords [ Wed May 12, 2010 9:58 pm ]
Post subject: 
Quote:
You, ah, did put a new filter in while you had the pan off...yes?
:roll: yes

Three little flathead screws and off she came.
Author:  SlantSixDan [ Wed May 12, 2010 10:01 pm ]
Post subject: 
Okeh, just checkin' 'cause I didn't see it.
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