73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Electrical => Topic started by: ChrisD on June 08, 2020, 12:36:10 pm

Title: 1978 C10 manual transmission, backup light switch at steering column?
Post by: ChrisD on June 08, 2020, 12:36:10 pm
Hi,
i looked why the backup lights doesn't work. Looking at rockauto, they only offer me a switch which is for installing into the manual transmission.
But the Saginaw 3 speed under my truck don't have any switches or position where i could install any switches.
At the steering collumn near the firewall, i've found this switch:
https://www.directupload.net/file/d/5844/f5yaijes_jpg.htm
I#ve Felt with my fingers, if i switch to the reverse gear, a metal plate would push the switch, but this one is damaged and also there were no wires.
I also have to say that i also didn't find any wires near by the transmission, don't know where the switch normally is.

Is this the normal backup light switch in 1978 for a 3 speed?
If not, someone has an idea, from which car is my steering column?

I'm also not sure, if the 3 speed saginaw is the right transmission, because looking at gmheritage they only listed tremec or muncy transmissions. But with this i have to life with. It's not easy buying another transmission in germany.

Regards
Chris
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: zieg85 on June 08, 2020, 02:09:36 pm
The 3 speed manual shift on the column has the switch near the firewall.
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: ChrisD on June 08, 2020, 04:22:35 pm
The 3 speed manual shift on the column has the switch near the firewall.

Hi,
okay then, but is the switch at the picture the right one, or if not, do you have a picture of the build in switch?
Where can i buy the switch?
I haven‘t found it yet.

Regards
Chris
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: bake315 on June 08, 2020, 04:35:51 pm
That appears to be the right switch. You can find it on the first page of the diagram here:

http://www.73-87chevytrucks.com/techinfo/7387CKMans//Wiring/ST_352_78_1978_Chevrolet_Light_Truck_Wiring_CK_10_30_Only.pdf


Can you post any pics of the transmission itself?  It should be the SM465, if it’s a three speed.
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: ChrisD on June 09, 2020, 12:26:32 am
Can you post any pics of the transmission itself?  It should be the SM465, if it’s a three speed.
Hi,
thanks for your reply!
it isn‘t a SM465 because i have a column shifter.
I‘ll post the pictures later.
The switch at the right side of the wiring diagram is another one, because it has more contacts than mine.

Regards
Chris
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: ChrisD on June 09, 2020, 02:32:18 pm
Can you post any pics of the transmission itself?  It should be the SM465, if it’s a three speed.
Hi,
thanks for your reply!
it isn‘t a SM465 because i have a column shifter and i put new seals and bearings in it. So it‘s definitive a saginaw 3 speed ;)
I‘ll post the pictures later.
The switch at the right side of the wiring diagram is another one, because it has more contacts than mine.

Regards
Chris
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: zieg85 on June 09, 2020, 03:12:31 pm
This is a reverse light switch from a 84 on up 3 on the tree steering column
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: ChrisD on June 09, 2020, 04:18:37 pm
This is a reverse light switch from a 84 on up 3 on the tree steering column

Hi,
It looks exactly like mine!
Okay, now i only have to find this switch at a shop.
I directly looked at rockauto, they don‘t have it.
But with you information i can start my search.

Thank you very much!

Regards
Chris
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: zieg85 on June 09, 2020, 04:44:50 pm
no problem, glad to help.  I have 2 parts column and 1 complete should I decided to put my 86 C10 back to original instead of a 4 speed on the floor
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: Mike81K10 on June 10, 2020, 11:50:05 pm
Just in case your interested in the switch on the manual transmission I have attached a picture, The connector and wires for my switch run under the shifter cover, which of course is on top of the center floor cover that is not shown in the picture (its removed).
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: ChrisD on June 14, 2020, 12:22:47 pm
no problem, glad to help.  I have 2 parts column and 1 complete should I decided to put my 86 C10 back to original instead of a 4 speed on the floor

Hi,
thank you, if you don‘t need it any more, write me.

@Mike, thank you for the picture! Poorly i have a column shifter, so i need another switch.

Luckily, yesterday i‘ve found the original part number of the switch and with it a shop who sell nos parts. The GM part number is 329816 and the shop is https://www.hiltopautoparts.com/
So for now i can‘t do anything than wait till the package arrives.

Regards
Chris
Title: Re: 1978 C10 manual transmission, backup light switch at steering column?
Post by: zieg85 on June 14, 2020, 12:58:44 pm
My site supporter status has elapsed or else I would contact you.  Glad you found one, I was out of luck on a replacement shift collar.