2 speed axle shifter

[Twatts44]

I’ve finally sourced a 2 speed axle and fitted it to my truck, originally it had a single speed axle.

Its a canadian built truck for the military, the twin speed for this year should have been a mechanical shift with a lever in the cab, does anyone have any pictures of the linkage etc?

Alternatively I may make it electric shift, any pictures of the actuator set up on later trucks?

 

I know I could go vacuum but that would be a lot more parts to find and there isn’t an abundance of parts in the UK!!

 

Tom

 

 

[Robert Harrison]

Im not familiar with  the  connection at the axel with the two speed but If it were I I would first look at fabricating a cable assembly.  Use silver solder on the ends come up with cable and shielding on line or use parking brake shielding coupled together. 

[rockingjd]

You don't mention your trucks year. I bought a parts truck a few years ago. The mechanical cable worked a vacuum switch on the firewall. The rear axle was vacuum controlled. The speedometer also had a switch that compensated for the 2 speeds.

[Twatts44]

I would say it’s about 1942, I’m not entirely sure.

I’m pretty sure the Canadian built military trucks had a completely mechanical shift system, not a vacuum, fairly sure they had a lever lever come up through the floor to operate the rear axle shift. 

[47 1.5 ton]

Plan on following your progress, hoping you go electric actuator! 

[MBSoPaB]

Tom, here's a pic of the vacuum actuator from a '47 farm truck.

 

Also, the lever in cab of a '41 mechanical 2-speed.

 

I'll see if I have any pics or parts of the old mechanical I took out of my '42 WFMA ~15 years ago.  They were brutally simple, nice formed steel hand lever, solid rod back to an intermediate dangling pivot from a frame crossmember, and another solid rod back to the mechanical 2-speed.  I can get specific pics of the latter from my buddy's '41, but it sounds like you've some decisions to make before I go randomly flooding your thread with pics.

 

Thoughts?

 

Brian A.

 

(MBSoPaB)

[Twatts44]

Hi Brian,

 

I reckon I'll go mechanical shift so any pictures/info you've got would be brilliant thanks ?

 

Tom

[MBSoPaB]

Tom, the following photos are from my buddy's '41 COE road tractor: the easiest thing in the yard to photograph without crawling around in the snow and slop.

 

Best,

Brian A.

[MBSoPaB]

Another 3 photos.

 

Brian A.

[steve s.]

 You have a nice looking truck. At one time I had a 1946 Chevy with a mechanically shifted two speed rear axle. It used a short rod from the bottom of the shifter to a bracket on the frame, and heavy flexible cable from that bracket to the rear axle. It worked very nicely, and the cable allowed for plenty of free movement between the cab, the frame, and the axle. Sorry, no pictures. . 

[Twatts44]

Brian,

Pictures are spot on thankyou very much, was going to fabricate something up anyway but is nice to see what it should resemble!

Will update with pictures/progress

[MBSoPaB]

Sounds like a plan!

I look forward to seeing your final solution, and am sure other owners to come will appreciate it being shared here on the forum.

 

About the only thing I feel compelled to add is that the shifter handle mounting is different between the COE (bolts to the base of the seat frame) and the conventional truck (bolts to a bracket on the transmission, under the floorboard).  That may not have been visible between the initial batch of pics and the later ones.  Otherwise, nothing fancy, all the ones I've dissected or documented have had simple angle iron and flat stock bracketry, clevise-type ends welded into straight lengths of ~ 5/8" or 3/4" OD tube.  The engineering of the pivots and joints appears to be ~1:1, as far as input and output movement in the joints; if it takes 3" of linear movement at the axle to make the shift, then it's 3" of linear movement at the shifter under the floorboard.

 

Hope your project goes smoothly!

Brian A.

(MBSoPaB)