general trans questions

[oldcane]

Hi guys. New here and lots of questions so I have to start somewhere. Just got a '73 charger that has been built up a bit but didn't buy from the guy that did the actual build. He also told me the auto trans has been rebuilt. The problem we see is that it won't go into 3rd until you get close to 50mph. Doesn't feel at all like it's even trying, just happy to be in 2nd. So I guess my question is does this mean:

1-needs to be adjusted
2-has some sort of shift kit so this is by design
3-it's getting ready to explode
4-could be any of the above

I'm hoping the concensus is 1.

Thanks.

 

[racedodge]

your throttle pressure rod needs adjusted. i believe there is too much pressure being applied in the valve body, hence it is not wanting to release from one gear to another.

here is a test.... put it in drive and bring it up to 45mph and then let off of the gas.. if it shifts into drive/3rd.. your throttle pressure is too high.

you will need to adjust the throttle pressure (aka kickdown rod) either at the carburetor or at the shift lever shaft.

 

[oldcane]

Excellent. What I heard was.....it won't cost a thing. Thanks. We'll give that a try this weekend.

 

[YY1]

Be careful not to leave it too loose, easy to cook the 2-3 shift mechanism that way.

 

[oldcane]

Ok, not sure what that means. Can you elaborate so I don't?

I also forgot to ask is will it hurt driving it this way for a while this week? Like I said it seems perfectly happy and not trying to slip in and out of 3rd or anything. Or just put it in 2nd and drive around town?

 

[YY1]

I've lost two 727s to loose or missing kickdown. Starts slipping going into 3rd, then after a few days- 3rd is gone. Very important to get proper setting.

 

[TheGodfather]

727 Line Pressure

Ok, not sure what that means. Can you elaborate so I don't?

I also forgot to ask is will it hurt driving it this way for a while this week? Like I said it seems perfectly happy and not trying to slip in and out of 3rd or anything. Or just put it in 2nd and drive around town?

I'm pretty sure its choice #1 and the throttle pressure needs some adjustment. I had the same exact issue with my 69 Bee last year. I'd try to make the adjustment yourself at the kickdown rod near the carb. There's a screw adjustment there. Turn it clockwise a couple turns thereby shortening the overall length. Then take it out for a spin and see if that helps. If not...try a couple more turns till you feel something different one way or another. Some transmission shops do have line pressure gages to check this very sort of thing too. If you don't get a response; then someone may have put a "Max Wedge" or "Hemi" HP Govenor in the tail. That will change the shift point upwards greatly and isn't great for normal street useage.

 

[racedodge]

Ok, not sure what that means. Can you elaborate so I don't?

I also forgot to ask is will it hurt driving it this way for a while this week? Like I said it seems perfectly happy and not trying to slip in and out of 3rd or anything. Or just put it in 2nd and drive around town?

too much throttle pressure can cause your bands to engage without any slipping in between shifts (i.e. overlap). if there is major overlap, the transmission will want to be in two gears at the same time, this can cause pre-mature wear of bands and some componetns as well as large amounts of stress on components to include the rear sprag.

 

[oldcane]

Thanks everybody. We'll check it out.