Lights on dash

[sanford66]

Hey All. This may be a stupid ? but I saw a reference to this in another thread. What are the "Tandom Lock" & "Overspeed" lights for on the instrument cluster? the 66 I am working on has them but my other trucks don't. I'ts got me stumped. Thanks. Joe

[budden]

that cluster must have come from a 5 ton or larger truck

[hewlett2002000]

could you post a pic? id like to see it.
thanks,
John

[sanford66]

Hewlet- This is the only pic of it I have right now. You can see a small circular idiot light on the lower left next to the factory gauges. The other one is blocked by the steering wheel. Joe

[hewlett2002000]

thanks. i had a 62 cluster like that. thats why i asked.
john

[el greco]

I discovered both of these lights on my '62 a month ago when I customized the dash. I have neither of these systems though and the turck was bone stock when I got it.

The 1960 Truck manual states" The purpose of this overspeed warning system is to warn the driver of excessive engine speed in an overrun condition (such as during down hill operation when the wheels may begin to drive the engine)."

It goes on to tell you about the light and the vacuum sensing switch in the governor. It appears to me that the dashes came setup for all possibilities, kind of a module approach for the day.

I can't find the info on the tandem lock, but sounds like an axle related option to me.

Tony

[el greco]

Ok, I found the circuit diagram for the two-speed axle on page 9-58 of the same manual. It has a warning light that I assume is the tandem axle light.
On page 5-70 it talks about the two-speed axle electric shift system. I am pretty sure those axles only came on trucks bigger than 3/4, so they probably used that dash on all their trucks back then.

Tony

[sanford66]

Hey el greco- Thanks for the great info, helps a lot. Joe

[Brad54]

From what I can tell, it was more common for the big commercial trucks to have full instrumentation, and the Overspeed and Tandem Lock were built into those gauges.
For my '62 full instrument cluster (don't have a tach yet!) I took a parts cluster and switched one of the holes over for a turn signal indicator. The '60-'62 dashes had a single green indicator for both signals--it didn't have one for the left and one for the right.
Since I had to choose, I left the Overspeed indicator in there...When I get a tach, I'll hook a shift light to it and mount the shift light behind the Overspeed indicator, just for fun. It'll really be more of a joke if anyone else ever drives the truck.

-Brad

[63 & 64 Bowties]

Originally Posted by el greco

I discovered both of these lights on my '62 a month ago when I customized the dash. I have neither of these systems though and the turck was bone stock when I got it.

The 1960 Truck manual states" The purpose of this overspeed warning system is to warn the driver of excessive engine speed in an overrun condition (such as during down hill operation when the wheels may begin to drive the engine)."

It goes on to tell you about the light and the vacuum sensing switch in the governor. It appears to me that the dashes came setup for all possibilities, kind of a module approach for the day.

I can't find the info on the tandem lock, but sounds like an axle related option to me.

Tony

Tandem lock is used on 3 axle (10 wheelers) trucks only. In normal driving, only the front axle (second of three) pulls and the rear (rear-most) just "tags." For slippery roads or if you loose traction in dirt/mud, you flip a switch on the dash which activates the "power divider" and both rears pull.
I"m not smart, I'm just an ole "trucker."

[sanford66]

Thanks all! Joe