Do I need to rebuild my 904. No third gear.

[my5thmopar]

72 Dart 904. I was doing regular maintenance today checking fluids. I was out running around several places. I have a small leak and have to add AT fluid once in a while. The trans was hot and cycled through gears and was at the add 1 pint mark. I went to the parts store and put in a pint while there. Went to the grocery next door down. When I started back home the trans shifted to third and nothing. Stopped and started again trans shifted 1,2,3 and nothing. The engine just reved like in neutral. 1,2,R all work. I tried manually shifting but still nothing. What might cause no third? Adjustment or hard part failure?

 

[william]

Sound like a sticking shift valve

 

[bamamopar]

72 Dart 904. I was doing regular maintenance today checking fluids. I was out running around several places. I have a small leak and have to add AT fluid once in a while. The trans was hot and cycled through gears and was at the add 1 pint mark. I went to the parts store and put in a pint while there. Went to the grocery next door down. When I started back home the trans shifted to third and nothing. Stopped and started again trans shifted 1,2,3 and nothing. The engine just reved like in neutral. 1,2,R all work. I tried manually shifting but still nothing. What might cause no third? Adjustment or hard part failure?

It must be something in the water down in the south!. I got my dart out to pick my kid up last week and everything was good. Stoped to get gas and took off and shifted to 2nd great and went to 3rd it acted like it might want to go into 3rd but wouldn't. So I went today and got some Lucas trans fluid. Hopefully that will help it.

 

[fishy68]

Must be a valve body issue if it has reverse. If it had no reverse I'd say the front clutch was smoked.

How many miles does it have on it? Has it ever been rebuilt? If it hasn't and it's an original 72 trans. that means it's over 40 yrs. old. Rarely does anything last that long without needing rebuilt, but you may get lucky with the Lucas, but you have to remember that all those additives are just a band-aid.

 

[Rengo]

The rear bands might not be releasing, I had to have mine fixed last summer. It was not shifting easy at all but is all better now. Good luck with your tranny problem and keep us posted..

 

[fishy68]

The rear bands might not be releasing, I had to have mine fixed last summer. It was not shifting easy at all but is all better now. Good luck with your tranny problem and keep us posted..

It only has 1 rear band and it it doesn't release the trans. would lock solid as soon as it shifted into 2nd gear.

 

[TrailBeast]

Make sure your throttle pressure linkage is adjusted properly. (not hung all the way back)
Reverse uses an internal line pressure that is twice the normal forward pressure, so it's very possible that reverse is not far behind in going out but just hasn't yet.
I'd bet if you drop the pan you'll find clutch material in the pan.

 

[my5thmopar]

I've got noise. I’m getting a pretty bad thumping noise. It is especially bad when backing up a vacant street for 100 yards or so. It looks like I'll be pulling it. I would like to do it myself. I have rebuilt engines, differentials and various other machinery so, I think I can do it. Thanks

 

[TrailBeast]

I've got noise. I’m getting a pretty bad thumping noise. It is especially bad when backing up a vacant street for 100 yards or so. It looks like I'll be pulling it. I would like to do it myself. I have rebuilt engines, differentials and various other machinery so, I think I can do it. Thanks

There are a lot of good video's on youtube on them these days.
Sounds like your going to need at least a rear planetary set on top of the rebuild kit.

 

[Mad Dart]

Lucas is some good stuff. My sons Ranger would be in gear and go to Neutral status under throttle, it would just Free Revv in gear, weird. So I put about maybe 10oz of Lucas in it almost 2 years ago. No problem since.

 

[william]

I've got noise. I’m getting a pretty bad thumping noise. It is especially bad when backing up a vacant street for 100 yards or so. It looks like I'll be pulling it. I would like to do it myself. I have rebuilt engines, differentials and various other machinery so, I think I can do it. Thanks

it's a simple trans to rebuild just get a good manual.


http://smrtrans.tripod.com/smrtransmissionsintro/index.html
or
http://coperacingtrans.com/
can set you up with everything you will need for parts and manuals.