727 experts - reverse trouble

[robertob]

I've been driving my truck daily and so all the little things that didn't bother me are becoming more noticeable.

Biggest issue right now is with the 727 trans. It shifts great in all forward gears, but it's lazy going into reverse and slips a little. I don't have another car right now so I'm hoping I don't need to pull the trans.

Fluid seems clean and full, and like I said no problems with kickdown or anything.

I may drain & refill this weekend, and replace the filter just to see what's up. And adjust the bands.

[my5thmopar]

Kickdown doesn't have anything to do with reverse. Look for reverse band screw in the pan, they do come out. Reverse servo either seal bad, missing snap ring or cocked in the bore. Reverse band out of adjustment or broken. Most likely nothing to do with the valve body. Enjoy your transmission fluid shower. Craig

[robertob]

Kickdown doesn't have anything to do with reverse. Look for reverse band screw in the pan, they do come out. Reverse servo either seal bad, missing snap ring or cocked in the bore. Reverse band out of adjustment or broken. Most likely nothing to do with the valve body. Enjoy your transmission fluid shower. Craig

Thanks, I'll let you know what I find. It does eventually reverse so something is still there. Got one of the fancy pan gaskets from the dealer today and plan to tear into it on Sunday morning.

I ordered a new reverse servo piston and seal from ebay.

[marklein]

Hopefully just an adjustment. You have to pull the reverse servo pin to remove the servo. That requires removing the valve body and extension housing. If that is needed, don't remove the servo pin completely, just push it back far enough to let the center drop down. Otherwise, the anchor for the other end of the band may fall down. You will probably find it just needs adjustment.

[robertob]

Broken band apply linkage.

Everything else looks fine - band has plenty of meat, drum is not glazed or scored. The low/reverse servo piston and seal even look pretty good, but I ordered a heavy-duty replacement already so might as well swap it out.

Going to call some tranny shops on Monday and hope someone has the parts sitting around.

[712edf]

Glad you found a concrete answer.

Bucky

[my5thmopar]

Broken band apply linkage.

Everything else looks fine - band has plenty of meat, drum is not glazed or scored. The low/reverse servo piston and seal even look pretty good, but I ordered a heavy-duty replacement already so might as well swap it out.

Going to call some tranny shops on Monday and hope someone has the parts sitting around.

Yup...I've seen that before. My book says the part changed in 1991 when it went from a 6 to 6.25 drum. Hum didn't know that. Gald you figured it out.

[robertob]

Glad you found a concrete answer.

Bucky

Me too, and I'm very glad it's something I can fix without dropping the transmission and pulling all the guts out!

Although as I was laying there with ATF running through my hair I was thinking that having it sitting on a bench upside down would be nice right about then.

[marklein]

I've seen that before . Rare failure, bands usually break before that happens. Just be sure you remember which way it came out. Only goes in one way. Glad it can be fixed in the truck, always a bonus when the trans can stay in the truck. If you cannot find said part, I'm sure I can find one.

[robertob]

Got it all back together and working. However, I discovered that there is no way to get that link assembled back into the trans between the case and the band. So after fighting it for 1/2 hour I filed off the tabs on one side of it so that I could twist it back into place in two pieces. I prodded at it with a pick and screwdriver and satisfied myself that it won't come apart once installed, but worst case if it does I have to pull the trans anyway.

I do notice that now for some reason the gear selector lever is much harder to move than before, if it doesn't get easier I'm going to have to drop the pan and vb again to investigate. Maybe I got something crooked in the shift detent

And it still bangs into reverse, which makes me cringe every time.