Tranny downshifts too much

[The_Handier_Man1]

From: Fastbanshee011  (Original Message)
Sent: 1/12/2006 10:45 PM

Ok here is my problem I have a 1978 Dodge F40 with a 440 engine. I not sure what tranny is in it. We went to the dezert last weekend and on the way home the tranny kept shifting from drive to second. It was even doing it on flat highways. Any ideas?



From: OldEdBrady
Sent: 1/14/2006 11:46 AM

Solving the problem may be on the message boards, but, if not, I'm sure you'll have answers before too long.

As far as the tranny is concerned, I'm willing to bet it's the A-727, since you have the 440.



From: Tymhoff
Sent: 1/16/2006 12:07 AM

I would say to check the downshift linkage to make sure it is adjusted correctly. Was it doing it on 8 heading west from the desert?(If you're talking about the Glamis area) If so, is it possible that there was a head wind and you were just having to push the gas pedal harder?



From: Fastbanshee011
Sent: 1/16/2006 8:12 PM

Yes it was doing on the 8 west heading to San Diego. I pulled over an got out to check things out and there was no head wind. How do I adjust the linkage? I know what to adjust but how do I know when it is right?



From: Slantsixness
Sent: 1/19/2006 9:31 AM

I posted this before, I don't know what happened to the post, though?

An F40 would indeed have a 727.

Sounds to me like the trans throttle linkage may be stuck in wide open throttle position? check the linkage and adjustment, then look to the throttle valve in the valve body...

If not, the transmission cooling lines / cooler / filter could be clogged and cause most or all of these symptoms. Unfortunately, continuing to drive it like this will burn up the transmission quickly even if only one of these items is clogged.

And today I'll add this.

To adjust, it's pretty simple:

loosen the reatiner bolt on the shift down rod. (all springs and retainers must be in place)
extend the rod to the fully open throttle position (trans shiftdown lever all the way to the stop, this is a counterclockwise motion, or the lever toward the rear of the trans. You can see the trans lever with the engine cover off but it's behind the engine cover area, under the van floor)
while holding the lever full throttle, open the carb full throttle. (make sure choke is off, and if 4 barrel, that all 4 barrels are wide open.)
Tighten the retainer bolt.
Most importantly:

The shift down linkage MUST work perfectly smooth, and have a return spring on the shift down arm to the throttle shaft. If you have an aftermarket 4 barrel carb, be sure you ar using the correct linkage adaptors (yes they sell them, and you need them).

Hope that gets you going, and not in second half the time!

Tom



From: Fastbanshee011
Sent: 1/19/2006 10:35 PM

Thanks for the help Slantsixness. I will give it a try this weekend and see how she does.



From: Fastbanshee011
Sent: 1/22/2006 5:44 PM

Ok I just replaced the tranny oil and took it for a test spin and still have the same problem. What socket do you use to adjust the bands? The one that I used just kept slipping off the adjustment screw. Im going to try adjusting the bands and the kick down linkage and see if that helps.



From: Slantsixness
Sent: 1/24/2006 8:02 AM

Kickdown Band Adjustment:  Locate the kickdown adjuster on the Passenger side of the transmission, Clean around it well, so that the locknut will spin freely when loosened.  Loosen the locknut about 5 turns so that it does not bind the adjuster.  Turn the adjuster in by hand and tighten it to 72 inch/ pounds, then back it out 2 1/4 turns.  Hold the adjuster while tightening the locknut.  Done.


Note! that is 72 INCH POUNDS, not foot pounds. and don't forget to back the adjust ment screw back out.

Most of the time, I've been able to adjust the screw (with the locknut loose) by hand, unless something is wrong...

You don't have to take the tranny apart for this.


Tom



From: LowellNew
Sent: 1/24/2006 5:31 PM

Tom is right, periodic band adjustment are very important for a healthy Dodge transmission.  Even the manual for my newer Dodge p/u calls for periodic band adjustment.