The Stovebolt Site Forums The Shop Area General Truck Talk 1937 Chev Speedo Cable question(s)

The other day I learned that the speedo cable in the '37 doesn't "like" the period correct 1937 gauge I am retro fitting into it and will not connect to it... (the present cable was attached to some new after market gauges which came with the truck but have now been removed)

After a look at an old broken metal wrapped speedo cable I have here I see that the end connecting to the speedo itself has to have a "large square end" on it (the terminology used in the Jim Carter's catologue) which looks to be about a 1/4" or 3/8" square brass tube piece on the end of the speedo cable...

I see from JC's catologue that the same cable was used 1937-72 BUT that the newer versions don't have the "large square end" on them...

Does anyone know if one of these newer cables would work and if the square end connector can be added in some way? Is there an adaptor available? Was the large square end used in any newer years more readily available from a FLAPS store?

Thanks in advance for your help...

~Trev

I'm not sure I understand your situation. The speedo cable in my 38 is similar to all I've seen in that it's square and about 1/8" across. I don't understand the 3/8" thing. Are you talking about the metal housing the cable runs in?

No tiny... that is just a metal wrapped cable...

I am talking about the "speedo" end of the cable (not the tranny end)...

The back of the gauge is much like a standard speedo except the square end of the cable fits OVER a square piece that comes out of the back/center of the gauge and then the end screws onto the gauge as one normally would...

Jim Carter's differentiates this kind of cable from the others (1937-72) with the "large square end" addendum I mentioned earlier so clearly there were two types... I just happen to be "lucky" enough to have the hard to get type (why am I not shocked?)

Yours sounds like a standard speedo cable... mine is basically one male end at the tranny and the "large square end" at the speedo is female... does that help?

~Trev

Trev, a pictures worth a thousand words!

You got me...

Ditto with the pics, maybe a truck speedo is different because I was referring to the speedo end of mine, not the tranny end. The speedo end on my coupe is just like any other I've ever messed with, 1/8" square cable that fits in a like hole in the speedo & the cable housing screws to the speedo base.

I have a call in to the local place I bought my king pins for my '36 and they're trying to figure out if they have the right cable or not as we speak... hopefully they do...

I guess the '37 and '38 speedos are quite different based on what you've said, tiny...

Mine has the typical screw on connector but it is what is in the center that makes it different... the '37 speedo has no hole... instead in it's place is a square piece that sticks out of the center of the gauge...

The cable goes over that, then the round screw on connector slides down and spins onto the back of the gauge to lock the cable in place...

I can try to take a pic a bit later if the shop doesn't have what I want... at that point I'll be scrambling to get something that will work... the count down to my first show has begun... I have 2 weeks to get the '37 finished, everything working, get it inspected and licensed...

~Trev

I don't have a pic of exactly what I mean yet but I found this one on epay which shows the back of the speedo gauge (on the left)

If you look in the hole in the center you'll see that square piece which is what the center of the speedo cable mounts over...

Now does it make sense? Hope so...

~Trev

I hace a spave speed-o for 37-38 that uses the same big cable end only I think mine is the female to the one you pictured. I have to go look and see. The big cable may be something to do with the big trucks and/or the two speed rear axle. Joe

Apparently there are more speedo cables than I was aware of, Joe... especially if yours is different than those I mentioned, the standard one and the one with the end like mine...

As a footnote, VERY nice truck you have there... I hadn't seen it before but was very impressed by it... nice!

~Trev

I have the same issue on my wife's 39. I have contacted a gentleman in Nebraska. He may have two cables with the propoer ends for us. He should know by tomorrow if he has them and if they work. I'll keep you informed.

Vlad

I hope so... still looking for one...

The weird thing is a buddy of mine asked why I wasn't using the speedo cable out of my '36 since it is just parked anyway... I figured great idea, removed it, cleaned it up and it is healthy... HOWEVER while it fits at the square speedo end it does not fit in the tranny... the cable has a round end with two burrs on it and the turbo 400 tranny needs a square cable...

I guess it just goes to show if it ain't one damned thing it';s another!

Too bad I see Jim Carter's has them in the catologue but apparently don't actually have stock...?

We should contact Uncle Alvin (Achipmunk)...

There's a guy who knows where to find '37 parts like this and never seems to have ANY problem doing so...

~Trev

The Turbo 400 gear is plastic, so with a little work, you could get the cable to work. Trans mission shops sell the gears for a few dollars, so it might be worth a try. Could you drill out a piece of square bar stock and silver solder it to the end of small cable that fits the trans? just thinking out loud.... Joe