Replacement Turn Signal Switch for GMC's?

[GMCNUT]

Hey guys - I know this subject has been beat to death way before I got to this problem myself, and I did read Jolly's Electrical page etc, but need to ask for your opinions anyway.
My 66 Suburban turn signal switch seems to work as far as "clicking" into left and right positions, but after checking all electrical connections and grounds and making all that right, the turn signal switch only works in the Right hand position. When I go Left, the turn signal light on the cluster lights up but does not flash. So I have decided repairing or replacing the turn signal switch has to be the answer because the headlights and taillights work, and Right side turn signals work, and the Right side brake light works but it is the only one that comes on when I depress the brake even after ensuring the brake light switch and headlight dimmer switch are new, working and grounded, and the taillights are grounded. I would love to just repair my existing almost-fully-working original switch, so question #1 is: I have a 64-66 Chevy switch brand new in the box, and was wondering if any of you thought I could unplug the harness and plug it into my existing switch and fix it? seems like I remember the two witch types do not interchange wiring harness-wise?

I saw on Jolly's electrical page where a 63 Chevrolet turn signal switch will supposedly work in a GMC switch housing, so I ordered one, but unlike the 64-66 one, this one came with no horn contact or upper column bearing, and the plastic switch body is not the same as the 64-66 one, so despite the two looking so very similar, the horn contact and bearing from the 64-66 switch cannot be used in the 63 plastic body (figures). So I seem to be upside-down here at the moment. Could simply be that I accidentally ordered the wrong 63 switch and did not notice I was getting one with no upper bearing, and simply need to order the upper bearing and horn contact assembly for it.

So I need to know if everyone else is just using these 63 Chevrolet switches, or if there is any hope of me simply using any of the above parts to fix my existing switch, or what - see pics below of the two switches I have.
Last option is to switch to a 64-66 Chevrolet Switch housing on the column, then the new Chevrolet switch would fit and eliminate this problem forever. Maybe that's the ticket - I do have a spare 64-66 factory automatic column switch housing I could use I suppose....thoughts? I hate switching GMC-specific parts out for Chevrolet stuff even though I do like and own several Chevrolet trucks - I just don't like cross pollinating if I don't have to

[AZKen]

This clearly states that it works with 64-66 GMC.
http://www.classicparts.com/1963-Tur.../#.VpGNTOlIg5s
I have never seen a switch that included bearing and horn contact. But I haven't seen everything.
Please explain what exactly does not fit. What can not be transferred from old to new. The switch does fit 64-66 GMC as stated by the vendor if you have a 64-66 Stock GMC column to begin with and has not been modified or is not Chevrolet, etc.
The cancellor and upper bearing are sold separately.
http://www.classicparts.com/1960-66-.../#.VpGRA-lIg5s
http://www.classicparts.com/1960-66-.../#.VpGQwulIg5s

WHEN A BRAKE LIGHT FILLAMENT IS BURNED OUT IT IS ALSO THE TURN SIG AND WILL NOT FLASH AND SCREWS UP THE WORKS
That may be your only problem.

[GMCNUT]

Thanks Ken - so here's what I ended up doing - I didn't like that the 63 Chevy switch comes with wires colored differently than 64-66 but decided to try it anyway, and it did install fine and I re-used the original upper column bearing from the GMC switch to fix that issue. 64-66 reproduction switches come with this bearing and horn contact but apparently the 63's do not. So after installing this switch, my brake problem was solved, but now when I turn on the Right side turn signal, BOTH rear lights flash - the drivers side flashes normally in the left position. I can only assume this means the brand new turn signal switch is faulty out of the box and there is likely no fix other than to order and install yet another just like it.

[AZKen]

Don't worry about wire colors. Hook up the correct functional wires together. Also some switches have 6 wires, some have 7. The seventh is for emergency flashers. Make sure that you don't have that included in your wiring. I am SURE that you are very close to getting it fixed as you have it now. I would not abandon what you have done until you check and double check the hookup. I would NOT assume the new switch is defective. Your problem (if all bulbs are good) is probably a mix up of wiring due to the colors. You need to absolutely write down each color of wire for each unit and what it does. Then check your wiring carefully. Take it slow on a good, peaceful, quiet day. Let me know. Both rear tails can only flash if they are wired wrong. Your rear left must somehow be hooked to the right. Let me know if your flasher has two or three blades. Until you have convinced yourself that you have done something wrong you will not find it. Forget thinking faulty parts until you are exhausted and 100% sure. I say this as your friend and personal motivator.

[GMCNUT]

Ah ha - thanks Ken - that 7th wire thing sounds interesting....let me check. So the 63 switch came with the usual ribbon of wires and they were pre-clipped in the usual C shaped connector housings in the order they are supposed to be for a 63 truck - so all I did was add the Grey wire for my auto column indicator light, and add the black wire for the horn to each of the only open slots where they belong. So not sure how it could be wired wrong - was thinking it had a messed up assembly in the top end when it was assembled at the factory, or has a blade touching something its not supposed to touch under the cancel cam where all the little brass contacts are set. Will check my ribbon and see how many wires there are. My flasher only has two blades

[GMCNUT]

Well, based on the attached picture above of the 63 switch I used, it only has the standard 6 wires, so not sure what to do here next....

[AZKen]

6 wires with a two blade flasher is OK. It does look like six wires. And I see the BLK for horn and GRY for indicator light as you said. Looks like 63-66 are the same wiring per this diagram. So the colors should, in fact, match. Follow the tail light wires from rear to brake light switch, to flasher and to turn signal switch to be sure it makes sense.
https://www.google.com/search?q=1963...frGk-YqQ9EE%3D
This is from Jolly's page. If you have not gone there, then go there and read where each wire goes and follow each wire all the way, to see where the problem is. He lists each wire below the diagram.
If you feel that the switch is defective it's your choice to send back, wait for a new one ,and try. I would check the new switch on the bench to see if it works at each lever position. After I checked all of the above.

[rtunison]

Hi gentlemen,

I saw your post about wiring a turn signal switch. I have done a lot of research on this and the Chevy's switch do not work on GMC's - and the switch needed is very specific to the 1963. The correct part number is 2440829 for 1963 "G" series. The switch wire colors are identical to the Main Wiring Harness colors of the truck.

In later years, GM decided to use GM part number is 2452507 for "F" model 1963 trucks. You can go to http://www.gmpartswiki.com/getpage?pageid=24576 to verify.

The only difference is the color of the wires. GM provided an "Instruction Sheet" in the box that details which color wire connects with the truck's Main Wiring Harness. Otherwise, the turn signal looks exactly the same!

Please see the attached scans.

I do have an extra NOS switch #2452507 that I bought on eBay several years ago for $149.94. Let me know it you are interested. Not looking to make a profit on this, just to cover what I paid.

Best!

Ron Tunison
Hartsville, PA
1963 GMC 1500 Fenderside 4x4

[GMCNUT]

Thank you Ron - so when you say the Chevy switch does not work in the GMC, let me clarify that my GMC is a 1000 series 1966 model, so the 1963 Chevy switch was recommended as a means of getting a switch that would fit the GMC upper column housing. This does work, and all lights work now, but when I click to turn on the Right turn signal, both rear lights flash. Its a brand new switch so not sure why this is. The old correct original metal GMC TS switch I removed would work in the right position prior to taking it out, and only the right side would flash as it should - so the variable and "what changed" here was me installing the 63 reproduction Chevy switch - thus, it has to be the problem. The switch I installed had all the wires pre-configured in the clips so I inserted them into the female under dash connectors with no mods and all the wires do correlate to the diagram you provided (thank you by the way). So I checked and the Green wire in the factory truck harness is indeed connected to the Violet wire from my new Chevy switch as shown for the right turn signal so this much seems correct. I think the problem is in the top end of my new switch - a buddy said they ordered and installed three switches in another guys truck before they got a good one that worked straight out of the box, so I may have got a dud here - can you post pics of the NOS switch and harness you have? I may buy it to fix this issue I have rather than buy another aftermarket one. I also have a 1963 Chevy that needs a switch, so if your NOS one is a 63 GMC switch and will not fit a 64-66 GMC upper column housing, maybe it will fit my Chevy?

[AZKen]

It is good to have that info Ron. I believe you are saying that for 1963 there is a problem with using a Chevy switch. The poster here is asking about 1966, I think. The vendor says his 1963 Chevy switch works for 64-66. Our Jolly page info says in 63-66 GMC used the 1963 Chevy switch. I do not know where the poster got his switch but it seems like it physically fits, connectors mate and operates mechanically. As far as operating correctly electrically, we are still working on that. I am sure that if the switch is not bad out of the box, it can be made to work electrically with minor rewire. Possibly with your info. If a switch fits in all aspects physically, accepts the bearing and horn parts, etc. It can be made to operate electrically. As I've said before, wire colors not matching is no sweat. Connect proper function to function on ANY electrical item in ANY truck. These switches are fairly easy to test for each wire's function.