Saginaw? Tranny question

[Chevy nutcase]

Guy I bought my 66 c10 from said this was a Saginaw 4 spd. I looked a bit for something like it but all the images that come up when searched show shift levers and linkage on the driver side. I need to get my reverse lights for Pennsylvania to say it's ok to drive and I'm having trouble locating where or if this thing has a reverse shift indicator switch. I really dont want to put the backup lights on a toggle. I'm pretty good identifying engines and auto transmissions, but manual gearboxes are Greek to me.

[cwcarpenter98]

That's either an SM420 or SM465 judging by the second picture

[VictoriaHardware]

I say 420.

The reverse switch is an external thing on top near the shift lever. Unfortunately very rare to find one of those. You're probably going to have to resort to a toggle switch, at least until you find the proper switch.

[Chevy nutcase]

Originally Posted by VictoriaHardware

I say 420.

The reverse switch is an external thing on top near the shift lever. Unfortunately very rare to find one of those. You're probably going to have to resort to a toggle switch, at least until you find the proper switch.

Yea after poking around a while I do indeed lack the option for a reverse switch so I'm thinking I have the sm420. Apparently only the last year of 67 was the only one to have this option. Now I really need a T5 lol. Toggle switch it is but I dont like it lol

[350TacoZilla]

Years ago I made a small bracket that held a cheapie horn button up beside shifter, when you put truck in R it would press up against the button. Days before cell phones so no picture but it was just a ugly L bracket basically. Nowadays there are more options for small momentary switches so I'm betting you could do it much cleaner for under $10.

[Chevy nutcase]

Originally Posted by 350TacoZilla

Years ago I made a small bracket that held a cheapie horn button up beside shifter, when you put truck in R it would press up against the button. Days before cell phones so no picture but it was just a ugly L bracket basically. Nowadays there are more options for small momentary switches so I'm betting you could do it much cleaner for under $10.

I thought about something like that. I wouldn't do anything exposed but if I can fit it under the shifter boot its definitely an option

[twoskies]

picture of switch on sm465, its broken but line shows where it is

hope this helps

[Chevy nutcase]

Yea I think mine is missing that. I also heard that even if its broken it has to be in place for the tranny to work.

[Accelo]

Originally Posted by Chevy nutcase

Yea I think mine is missing that. I also heard that even if its broken it has to be in place for the tranny to work.

That isn't true.
If you can plug the hole, so it doesn't leak, it will function without the switch.

[Chevy nutcase]

Well it would appear the chevy gods took pity on my plight. I was fully prepared to run a toggle for my reverse lights until I followed the existing wires up to the firewall and into the cab which I thought was odd because the column was not a 3 in the tree version and there was no existing toggle. I followed the wire under the mat and to the shifter and I felt the boot and there was more in there and I found this. Someone partially stripped the threads with the wrong thread nut. A fine thread 3/8 fit nicely with some med loctite and voila the lights work in all my searches I never saw this type switch. The other photo is one of a pair of helper springs. Wondering if there's a demand for these or if anyone local is interested in them.

[cwcarpenter98]

That's real nice you have the factory switch still in place and that it still works. For someone adding the overload springs to their truck, they would also need the plate bolted on to the trailing arm. You'll probably end up having to replace the u bolts once you remove the old ones though

[Accelo]

That's really cool. I have seen my share of these 4 speeds and don't recall this switch in this local. Typically I repaired newer versions. When the truck is shot and nothing else works the SM465's are still running fine. I suspect the transmission is original to your truck for the above reason plus the wiring and matching switch were still intact. Well almost anyway. I like it when a plan comes together.

Frankly I wish my state (Washington) had some type of vehicle inspection.
A while back there was a van in the turn lane of a 4 lane road with his top A arm laying on the road. It was still attached to the spindle and the tire. How long does it have to be knocking to fall off?
Cheers.

[Chevy nutcase]

Originally Posted by Accelo

That's really cool. I have seen my share of these 4 speeds and don't recall this switch in this local. Typically I repaired newer versions. When the truck is shot and nothing else works the SM465's are still running fine. I suspect the transmission is original to your truck for the above reason plus the wiring and matching switch were still intact. Well almost anyway. I like it when a plan comes together.

Frankly I wish my state (Washington) had some type of vehicle inspection.
A while back there was a van in the turn lane of a 4 lane road with his top A arm laying on the road. It was still attached to the spindle and the tire. How long does it have to be knocking to fall off?
Cheers.

State inspections are somewhat a good thing when it comes to the doofus you observed but in classic vehicles that are driven minimally it's a pain in the buns. Besides the reverse lights I had to fix my turn signal because it didn't cancel after turning, the one knob on my defroster was broke off thanks to pot metal design but thankfully I found a guy on ebay selling a rebuild kit with steel levers, all 4 drums and hoses were bad and the icing on the cake was a tiny chip in my windshield in my field of view. I had a guy here today to fix it but he said it was already repaired once so it cant be done again so next week I'm getting a new windshield to the tune of $300 installed. Yay more $$$

[geezer#99]

Is the windshield replacement required to pass inspection?
If not I’d leave it alone.
You might be in for a shock when the old one gets pulled out. And don’t damage the rubber. You might need it.
Possible the channel is rotted out.

[Accelo]

My truck likely wouldn't pass. The headlights need aiming after the rebuild and the speedometer just quit working.
Yes it's a PITA. However you likely fixed stuff you would have gotten to sooner or later.
I'm not real sure bout the defroster guess it could be considered a safety item.

When I was a kid I owned a 1956 Chevy. The window-shied wipers broke when I was in Portland OR and had a 50 mile ride to home. Stopped at Circle K and purchased some shoe laces. Popped out the radio delete plate and tied the strings to the cables for the window-shield wipers. My buddy ran the wipers, by hand, all the way home. 50 years later we still get a chuckle about that repair.
Wondered if that would pass? LOL

[Chevy nutcase]

Originally Posted by geezer#99

Is the windshield replacement required to pass inspection?
If not I’d leave it alone.
You might be in for a shock when the old one gets pulled out. And don’t damage the rubber. You might need it.
Possible the channel is rotted out.

Yes the chip made it fail inspection and I have no other option. The gasket will be destroyed when removed I'm sure of that thankfully the guy I go to has them in stock. I was suprised. It's in good enough condition that I'm hopeful the surrounding area isnt rusted. The goop sealing the roof is also in good shape. Fingers crossed. Pray for me

[sstock]

You have indeed a Muncie SM420 made from 1948 through 1967 and beyond for some military vehicles. In 1967 the top cover was redesigned to incorporate a reverse switch for the backup lights. Here is a picture of that.
One year only make it a pretty hard find. There was an external dealer installed switch that mounted next to the shifter base, though, like post number ten.

[cwcarpenter98]

Originally Posted by sstock

There was an external dealer installed switch that mounted next to the shifter base, though, like post number ten.

That switch was factory installed on the 66 trucks because of the mandate for reverse lights beginning in 66. It was used on the 60-65 trucks when optioned with reverse lights or installed at the dealer

[sstock]

Thanks for that clarification