1 and 3 prong neutral safety switches

[J-440]

 Does it matter which one I use as long as I have the correct harness to the starter relay?  What's with the extra 2 prongs anyway?  Thanks again.

[Ghoste]

The single prong style was used up to the 68 model year when the reverse light switch was part of the shifter.  With the 69 model the switch was incorporated with the neutral safety.  (automatics)

[gtx6970]

the manual valve lever inside the trans is unique to each style switch. you can't change the  switch without changing the lever inside the trans

[Ghoste]

What is different about the lever Bill?  I ask because when I bought my 67, it had the three prong switch boogered into the harness and everything worked fine.  That was the correct transmission at that time, later I changed to a later model trans and at first still had the incorrect switch in and a couple of years ago finally installed the proper single prong and wiring harness and it worked again.  Was mine a fluke or is there more to it?

[J-440]

 Thanks as usual.  I originally had a 1 prong and replaced it with a 3 prong. Did'nt know you had matching parts to each switch inside the tranny.  Those 1 prongs are hard to come by.  Any way that a more modern 3 prong would work without going into the tranny?

[Ghoste]

The connector at the end of the wiring harness is obviously a lot different but as I mentioned, I had a couple of bastardized variations in my car and they worked.

[J-440]

 Ghoste...how did you wire yours up?  Since my safety harness only has room for 1 prong I just stuck it in the middle post of the switch (gonna change that!!). Just wondering if I need any other wiring from that switch.

[Ghoste]

I didn't, mine was boogered in there when I got the car.  Furthermore, it wasn't even the right connector, just one that fit and functioned.  That was why I left it in until I was able to get the correct piece of the harness with a proper end on it before changing the switch.  Truthfully I think it was just wired in there so that one needed was doing all the work and the other two hung out doing nothing.

[J-440]

 Hey if it ain't broke don't fix it right?  Thanks and have a good one.

[John_Kunkel]

The 3-prong NSS will work in a single-prong trans but not vice versa.

[J-440]

 What about the statement made by GTX6970 about having the right interior tranny part that goes with the corresponding safety switch? 

[Ghoste]

Thats what John is saying.  The "interior part" in one (a trans originally meant to have one) will operate both style of switches but if the trans is meant to have the three prong, then that is all that will work.
This would explain why my 67 could use a three prong switch but it would also have to mean that the later model trans I installed had to be modified before I ever got it.

[J-440]

  I hear ya. Thanks for clearing that up. 

[Bob T]

Hi J-440, I had the same problem in my car when I got it, 68 single post wiring but it had been boogied up and bypassed the starter relay when it had a 69 trans put in it years ago I'm guessing.
I had a thread up on here to find out what should have been in place and it was quite helpful with good replies. Thanks DC guys  

However, I made my own version to get past the starter relay problem and since the wiring was missing inside the console ( cut off 1/2 way across the floor and tucked into the sill coverplate ) I made a new loom with different and better functionality.
Micro switch 1 for reverse lights
Micro switch 2 ( roller tip ) for trans inhibit sw

Only had the light bezels so I had to turn up some collars to mount and retain the lampholders. I then had to drill out the rivet and blue diffuser out of the shifter PRND12 housing and mount a blue LED from the east side because the switches sat too high for the standard fitting . Just get a blue tinge coming through on the letters, looks good, happy with the result all round , rather than messing with the trans switches ( limited availiability of parts out here )

Bob

[gtx6970]

John got it right.
I knew it was something like that

[John_Kunkel]

Here's a pic of the internal levers (roostercombs) and the type of switch they mate to; '66-'68 is in the center, '69 and later on the right. As you can see, the center contact in the 3-prong switch will still make contact with the two "ears" on the earlier roostercomb.

[terrible one]

Here's a pic of the internal levers (roostercombs) and the type of switch they mate to; '66-'68 is in the center, '69 and later on the right. As you can see, the center contact in the 3-prong switch will still make contact with the two "ears" on the earlier roostercomb.

John, is the one on the left pre-'66 then? I have a NOS neutral safety switch like the one on the left, always thought it was the '68 style until your post.

[John_Kunkel]

The one on the left is used on the '60-'64 pushbutton trans, the '64-'65 console/column uses the center switch.

[Ghoste]

Do the 64-65 and 66-68 style interchange from a functionality standpoint?

[John_Kunkel]

Yes, the fit and function is the same.

[terrible one]

Thanks for the extra info John