won't lock in park

[1972sportcustom]

I have '72 360/C6. When I put it in park it rolls away. A guy told me a tab is broken off of the steering column linkage and its not a hard fix but requires removal of the steering column. He was thinking the park stop is not in the transmission. I've looked briefly over the shift linkage but don't know where to look for this parking stop. Maybe what i'm looking for is broken off. Any help?

[70_F100]

Are you saying that the shift lever won't stay in the "Park" position?

Or, are you saying that the transmission won't hold the truck when you put the lever in "Park"?

[fordman]

yes it could be one of two different problems.

[FORDification]

If the shifter will not stay in the Park position on the column, it's internal to the column. I did some research on this a while back and posted a bunch of pictures in the following thread that will illustrate the problem and how to fix it.

http://fordification.com/forum/viewtopic.php?t=9096

[1972sportcustom]

I can shift the column into park just fine with a positive stop. The problem is the truck rolls away as if it is nuetral.

[SteveC]

Ill place my bet on the something is wrong internally in the transmission then. Most likely either in linkage or the parking pawl that holds the transmission in park is damaged or the ring it locks into is damaged. Untill you get it fixed make sure your parking brake works well

[1971ford]

First you need to find out if this is a linkage problem or a internal problem with the tranny.
There is a good chance that something is not right with your column/linkage setup so it simply isn't shifting all the way into park.

Just use your parking brake and call it good

[70_F100]

Ill place my bet on the something is wrong internally in the transmission then. Most likely either in linkage or the parking pawl that holds the transmission in park is damaged or the ring it locks into is damaged. Untill you get it fixed make sure your parking brake works well

I wouldn't drive it much, if any, until you find out exactly what's wrong. You may have parts inside that are loose that could get into places they shouldn't be.

The "Park" function of the tranny is very simple. There is a rod that is attached to the shift lever on the inside of the transmission that goes through a hole in the case into the extension housing. This rod has a cone-shaped end that, when the lever is moved to "Park", pushes a lever inside the extension housing that engages with a gear on the output shaft, providing a mechanical lock.

Possible causes for your trouble would be:

1) as 1971Ford said, check and make sure that the external linkage is functioning properly
2) the rod has come loose from the shift lever, the lever is broken, or the rod is bent or broken
3) the bolts have come loose that attach the guideplate for the rod
4) the parking pawl or the shaft it pivots on is broken
5) the parking gear is severely damaged

The only thing that may not be repairable without tearing down the transmission is replacement of the parking gear, and I can't remember whether it comes off from the front of the output shaft or the rear. Everything else is a piece of cake.

[1972sportcustom]

Thanks for all the advice and info! I'll check the linkage and throw to make sure there is the full extent of movement in the park position. After that I think I'll look at the transmission diagrams to understand more.

The good thing is no one ever wants to borrow my truck!

But I am getting tired of block chalking my wheels while out running errands. People give me funny looks. Especially the ones parked across from me in shiny new cars.

[SteveC]

I'm glad that 70_f100 can explain better than i can.
I'm still learning in school and don't have a lot of experience

[1972sportcustom]

Thanks 70_F100. I found the Parking pawl diagram on the tech diagrams. I think this is getting me closer.

http://www.fordification.com/tech/image ... atic06.jpg

[70_F100]

Thanks 70_F100. I found the Parking pawl diagram on the tech diagrams. I think this is getting me closer.

http://www.fordification.com/tech/image ... atic06.jpg

That's close, but no cigar...

Here's the one for the C6: http://www.fordification.com/tech/images/c6_02.jpg

I would almost be that the 380505-S clip (top center) fell off.

[1972sportcustom]

Thanks again 70_F100. This makes more sense to me. I will check it out hopefully this weekend.

If I am remembering correctly, as the truck rolls away, I can occasionally hear a tick, tick, tick sound, which is probably the pin (7D071) rolling over the parking gear (7A233) as it is not fully engaged.

So it could be anything: something has come apart, maybe just wear, or possibly inadequate throw. I'll check for external linkage connections and throw first.

If its internal to the transmission, it will have to wait for the upcoming transmission rebuild.

[fordman]

if its internal you can get to it from inside the pan. probably is where the problem would be at. but the tailhousing comes off pretty easily too.

[1972sportcustom]

Excellent! This website and contributors are awesome!