Finding and fixing a very common auto tranny leak

[Meep-Meep]

This is on my 69 Dart GTS convertible. I stopped driving it a couple of years ago because it was gushing fluid from what I thought was a converter seal or something but didn't look into it until recently. The car needed other work so I just parked it. Looking into the leak issue more seriously I noticed the shift selector shaft was loose but not as loose as I have seen. Still, I decided to remove the valve body and trying a repair before proceeding with tranny removal. Well, looks like I got lucky and the thing stopped leaking!

What I did was put the VB in a mill, found the center of the shift shaft bushing then drilled it oversize. From a piece of bushing bronze I made a bushing and pressed it in the VB then drilled the bushing slightly undersize (about .020"). The shift shaft went in the lathe and I adjusted it in the chuck until I had the least amount of runout then took some cuts until I got a clearance of about .002". The result is a nice fit to the bushing and no leak! ..And me driving the car again!

 

[super-bee_ski]

Holy Cow!
Great troubleshooting AND great engineering resulting in a GREAT FIX!

I will bet, a good tranny shop might not have found it!

Good job Meep-Meep!

 

[69a100]

Don't ya love it when a plan come together, or in this case, something like that?

 

[moparjohnny]

great catch,would you say that most vb will have this problem after years of usage?would a new vb be in line for most trans or a fix like you made?most people are not as good as you with things of this nature,i know i could not do it,that why i said maybe buy a new vb if not to expensive.

 

[Meep-Meep]

great catch,would you say that most vb will have this problem after years of usage?would a new vb be in line for most trans or a fix like you made?most people are not as good as you with things of this nature,i know i could not do it,that why i said maybe buy a new vb if not to expensive.

Yes, that shaft takes a beating over the years. The detent ball has a pretty hefty spring and puts pressure on that bushing area, which after 45 yrs of use it ends up as it does. A new VB should fix the issue. ...It better fix the issue!

By the way, if any one is interested I can offer this as a service. Figure about $60.00 plus shipping. New VB seems to be about $200.00 or more.

 

[moparjohnny]

i will be interested in that meep, what i will do is find a spare one because my trans is not apart now and send it to you to fix and when i get my trans rebuilt just put that in. or is this part difficult to remove from trans maybe i can remove my self? this is a 727 bb trans. thanks

 

[GetX'd]

I'd call that a few steps up from shade tree ingenuity. Great thinking and great job. You saved yourself some coin with that fix.

 

[Greg Ducato]

That is a great fix, well done sir!

 

[Meep-Meep]

i will be interested in that meep, what i will do is find a spare one because my trans is not apart now and send it to you to fix and when i get my trans rebuilt just put that in. or is this part difficult to remove from trans maybe i can remove my self? this is a 727 bb trans. thanks

Not hard at all to remove. There is a big spring over the accumulator but if you know about it you won't get surprised. Pretty much anyone here can walk you through R&R-ing the VB. Also you may want to make sure your replacement VB will be compatible with what you have now. I'm not an auto trans expert (have rebuilt a few) but don't know all the little details. Or perhaps there is a VB that might be considered an upgrade to your car. Maybe start a VB thread?

 

[62 Dart Convertible]

Nice work Meep-Meep. If we were geographically closer, I'd ask you to be my go to guy for light machining.