Car - 1970 Dodge Challenger 340 4-speed. Chased an electrical Gremlin down to the reverse switch in the back of the trans. When I jump the harness switch, backup and dash reverse lights come on. However, when I plug in the harness, nothing. If I remove the switch and push it in with my thumb, everything works. I can see through the switch hole, that the reverse lever inside the trans it right up against hole. I confirmed that the linkage is adjusted properly, and when I manually push the reverse linkage as far back as possible, I can't get the switch to close. It's as if the little ball needs to be in another 1/8 inch or so. The switch looks like a factory part. Did anyone ever have this problem? Is there an improved or alternate switch that reaches a little deeper into the trans?

Did you try screwing it in with no gasket? I have seen where rebuilders use too thick of a gasket on them and it pulls it too far away from the lever. If you don't hear a physical snap or "clack" sound when you push the reverse lever into reverse there may be an internal problem.

Gus

There is no gasket to speak of. Just a tiny o-ring that I squished the crap out of. There is a positive snap when I put it in reverse. As mentioned, the lever is clearly visible in the hole and almost up against the case.

Even if it is properly adjusted, if there is still some adjustment left, I would shift the switch a bit more in the direction it needs to go to work. The worst that can happen is it won't work then (it may need a bit more movement), or the switch won't shut off, which means you need to adjust between what it was, and what it is now.

Sometimes everything has just enough slop to keep things from working. Then you need to add just enough adjustment to accommodate for the slop.

You might try a new style switch . I never compared them side by side for thread depth. You can get them from Passon, Brewers, Rockauto etc...

Gus

measure the depth of the hole with the trans in reverse and compare it to the switch if not too far off and
if you know anyone with a lathe they could likely trim it down. It will at least confirm the length of the switch is the issue which it likely is

Sounds like you're missing the spring that goes behind the ball in the switch. The spring is needed to keep the ball in contact with the lever. Without the spring the ball just bounces as it pleases in addition to nothing to make the contact in the switch work..

You could buy the new switch but I'd be pulling the side cover to find that spring - unless its laying on you bench somewhere !!

If the spring were out of the switch I would suspect the ball would also have fallen out Correct ?

The spring is there. When I push the ball in, it pops right back to the seated position.

You are correct he has no idea what he is talking about.

The switch should not have an o-ring on it. It should be a very thin gasket. This could be your problem.
Also, I recently tested an original switch and it worked by pressing the ball by hand. However, if I press it in too far the switch opened back up.

Mike - This is the one I used. It seems the o-ring is "new and improved" method of sealing the switch according to the description. I search the internet and they all have an o-ring. Also, I would suspect if its in to far and opens again as I shift into reverse, the light should come on briefly before going off. On another thread, Someone else had the same problem and they took the switch to a machine shop and had the face milled down. I would like to avoid doing this if possible.

F*** off !!

Take the reverse detent out. Put the switch in and see if it works.

READ THE ORIGINAL POST MORON ! He already confirmed the lever is going all the way and the detent is working correctly.

You can order the correct gasket from Brewers

I bet this new and improved switch is actually a switch for some other car that just happens to fit. "Sort of, almost, close enough, should work". Can someone measure an old switch and compare it to this "new" switch? Just for fun take the o-ring off and try the switch without it.

If you pull off the o-ring and screw it in does it work ?

ain't electricity problems fun ?

The o-ring seats in a bevel at the edge of the hole so its not really holding the switch out much . Pretty sure the switch housing is touching the trans case but worth a try.
Thanks.

I have a Ford with lots of similar problems. Part is probably made for a Torino or Edsel.