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| | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | speedometer adapter for 2 speed rear I believe, should have a vacuum or electrical connection to change ratio when the rear is shifted - I've always seen them on the back of the speedo
Bill | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 |
Paul,
Red IDed it.
My 54/55 GMC 2-ton COE has that type of adapter for the speedometer and two-speed rear-end. I think that Jim Carter sells a 9-foot-long cable with the wider end-cap needed for that switch (I hope it works).
I do not know how the 2-speed selector-switch attaches to the speedometer adapter but I will be dealing with it this summer as I put the painted COE sheet-metal back on top of the engine. Spanky will be my savior.
| | | | | Joined: Mar 2004 Posts: 6,236 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,236 | I agree it's a 2-speed speedometer adaptor. I'm not familiar with the older mechanical 2-speed linkage, could the dash mounted lever have been connected to the adaptor somehow? Mike B  | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | "Identify this part, and if you need one...you can have it!"
Paul,
If Red does not want it, I'll take good care of it (and pay for shipping).
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | I don't want it Tim, I've had 2 from TF big trucks I couldn't give away, finally went with a load of scrap  I think all of them had either vacuum or electrical switches that were connected to the shift mechanism [vacuum or electric] so when the rear gear was changed, the speedo "automatically" followed Bill | | | | | Joined: Jan 2007 Posts: 446 Shop Shark | | Shop Shark Joined: Jan 2007 Posts: 446 | Is the speedo adapter vacuum operated? If so, I'll take it if nobody else wants it Oops, I see tclederman beat me to the punch, LOL......Well, if tc changes his mind I'll take it | | | | | Joined: Feb 2004 Posts: 29,881 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,881 | There's supposed to be a small vacuum diaphragm or a cable from the shift selector to switch positions as the Hi/Lo selector is moved, IMHO.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 2011 Posts: 1,611 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 1,611 | Tim,
PM me your address.
Paul | | | | | Joined: Feb 2012 Posts: 84 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2012 Posts: 84 | That is the speedometer gear change for a 1946 or earlier Timkin 2 speed rear end. It is MECHANICALY shifted, operating off of the rod that runs from the transmission mounted shift lever all the way back to the actuator cable that moves the shift lever on the rear end itself. NO vacuum or electricity involved.
If you've got another, I could use a spare for mine! | | | | | Joined: Nov 2011 Posts: 1,611 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 1,611 | Sorry Chuck, Tim's got dibs on this one. | | | | | Joined: Nov 2011 Posts: 1,611 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 1,611 | Drydock, check your messages | | |
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