Converting from 3 spd manual to auto-have wiring ?

[69lemans]

I'm slowly accumulating parts to do the conversion. Have a choice between a TH350 or a 200-4R,I'm leaning towards the overdrive trans. I'm wondering if it's possible to wire up the neutral safety switch from the existing wiring harness,or will I need to change out the harness . Any help/tips appreciated

[big_al_71]

When we converted mine to auto from a 3spd manual that was one thing that we overlooked a neutral safety switch. I am going to subscribe to see what the answer is....

[Shon]

What shifter are you going to use? Normally there is a safety switch with it that you connect your current wiring to and it works just fine.

[JimKshortstep4x4]

You can modify the existing harness rather easily.

I located the purple #10 wire that goes to the starter solenoid at the fuse panel. I then cut the purple wire and soldered a two wire pigtail with the right connector for the neutral safety switch to the cut ends. The pigtail is about 10" long which will reach the neutral safety switch on the auto column so the connector can be plugged into it.

The backup light wiring was in place and it had the right connector on it.

I can try taking a picture if you like.

Jim

[Smitty]

I did pretty much the same thing as Jim. With the exception I found the plug that fit the neutral safety switch for the automatic column and changed out the plug for the back-up lights and did the purple wire. I can go out and check after work tomorrow and might be able to take a pic and post it then. I swapped from 3 on the tree to a 700r4 trans.

[69lemans]

Yeah,I'd appreciate a pic if somebody can get one. I'll be using the column mounted shifter.Where can you get an indicator lens for a 4speed automatic?

[Smitty]

These pictures aren't the best. But the green wires with the L shaped plug are the backup lights and the other is the neutral safety switch wires. It's been years but it appears that one segment of the purple wire comes from the wrapped bundle under the dash and the other is attached to a post on the back of the fuse box. If you look closely at the back of the plugs you will notice a small tab on the terminal. If you push the wire into the terminal a bit and use a small flat screw driver you can flatten the tab and pull it out of the terminal, After which you just have to bend it back a bit and you can slide it into the receptacle and its just like new. No cutting and finding terminals that fit. It looks stock. I'm not sure but I think the receptical for the 3 speed reverse light is different that that on the auto column. The receptical for the safety switch part was probablly snipped from a stripped truck at a yard. I think the 4 speed inticator is available at Brothers, LMC, or maybe even from one of the board venders. But to get it to align you will have to go to LoKar lilnkage which can be adjusted. I have this linkage but haven't installed it yet. It you go to the FAQ section and find the post where someone suggested an index for FAQ's there are a couple posts that may offer you a better picture of how to do it. But if I managed it can't be that hard. It's just that my memory isn't always the best on some of this stuff.

[Smitty]

If there are any direct questions feel free to email me and I will try to find the answers.

[69lemans]

The purple wire basically goes from the ignition switch to the solenoid,is that right? Thanks for the info,I think I can get it now

[Smitty]

'69 I think your more likely than not right. But I didn't pull the fuse panel off to see which terminal I plugged into for power. If there is no rush I might be able to do it quickly Sun. morning and respond.

[JimKshortstep4x4]

The purple wire goes from the ignition switch to the fuse panel side of the bulkhead connector. It picks up again in the outside bulkhead connector and goes to the starter solenoid.

Jim

[Grapdawg]

Wow glad I found this thread im about to do the same and switch my 3 spd to a th350. Would I need to do the same thing if im going to be using a console sifter. I have made a custom console and plan on using a B&M shifter. What would I need to do?

[69lemans]

Originally Posted by Grapdawg

Wow glad I found this thread im about to do the same and switch my 3 spd to a th350. Would I need to do the same thing if im going to be using a console sifter. I have made a custom console and plan on using a B&M shifter. What would I need to do?

If your using a floor mounted shifter,you won't be able to use the neutral safety switch mounted on the column.Check the paperwork with the shifter and see if they offer anything.