Help! I finally got the pushbutton A904 transmission back in my '64 Valiant, adjusted the cable shifter per Doctor Dodge's instructions (Thanks, Doug!) and the kickdown per the service manual. Reverse, 1st, and 2nd are fine, but it won't upshift to 3rd. Fluid level is fine. I tried readjusting the kickdown up to 1/4" either way, to no avail. Ideas? Please? Oh, and the one transmission guy in town who might know something about these just retired.

Ldavis@msn.com

If you posted somewhere else about where you got this transmission or whether or not you are certain that it was shifting into 3rd before it went into your car, I didn't notice.
Assuming that you are NOT certain if it was shifting properly before, I would check the following:
1)double check the linkage, just to be sure, but if all the other ranges work OK , this is probably not the problem.
2)You may need to disassemble and clean the valve body.
3)the high gear clutch may be burned out, or it is not applying for some other reason(blockage or stuck check ball) If the clutch gets overheated (from low fluid level before you got it or poorly functioning cooler) the seal will quickly become brittle and eventually it won't hold enough pressure to apply.
Scared yet?
The 904 is one of the simplest automatics ever made. It's been a while, but last I knew, you could rebuild one of those for under $100 (parts only!) If you can find a guy who can do one of those junky F**d automatics (enough checkballs and other teensy little parts to fill a piggy bank), he certainly could do your 904 if need be.


thelogs@cox.net

This is a fresh rebuild. My old trans sprung a major leak, and there were chunks of the case floating around inside. I finally managed to locate a trans rebuilder with a cable-shift 904. I flushed the trans cooler per instructions that came with the trans.
: Scared yet?
Past scared. A little angry! lol


dobie79423@yahoo.com

The service manual has a great "troubleshooting" section, you can do a pressure check once you are sure the linkage is working correctly.

I would pull out the valve body and hit the 3rd gear pressure feed port with air pressure. If the clutch is OK you will hear it apply with a solid "thump" and it will hold air pressure.
If there is something wrong with the clutch piston seals or shaft sealing rings, you will hear the air leak.

You can also check the valve body 2-3 shift valve while you have things apart. Just be sure the shift valve moves freely. (a small piece of anything can stick it)
DD

If the car can be driven at all, I would take it to the rebuilder before I did anything else except double checking the linkage. This should be HIS problem. I'm assuming ,of course, that the rebuilder isn't the same guy who just retired.


thelogs@cox.net

The rebuilder is not local - I went through a parts store chain to find it, after striking out with the local trans shops and junkyards.

dobie79423@yahoo.com