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| | | | Joined: Feb 2018 Posts: 116 Shop Shark | | Shop Shark Joined: Feb 2018 Posts: 116 | I found a 1948 2 ton parts truck. It has the 5 window cab and even the original radio in it! What I'm curious about is that the shifter has a button/switch on it like a hi/lo but the hi/lo switch is in the dash. What else could it be? | | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 |
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
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| | | | | Joined: Feb 2004 Posts: 29,750 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,750 | Is the 2 speed rear end vacuum or electric shift? It's possible the rear end has been upgraded to electric, and the dash button for the vacuum shift axle was not removed.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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| | | | | Joined: Feb 2018 Posts: 116 Shop Shark | | Shop Shark Joined: Feb 2018 Posts: 116 | I'll have to look at it again. It looked like the diff shifter still had the vacuum lines connected. Did the SM420 ever have a reverse lockout? | | | | | Joined: Feb 2018 Posts: 116 Shop Shark | | Shop Shark Joined: Feb 2018 Posts: 116 | Or possibly an overdrive? | | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | IF you have a SM420, the answer to both your posts above is...NO. Is the gear shift knob red and it can be pulled up and down or is it a flip lever connected to a metal rod going down to the transmission? Pictures would help. Mike B  | | | | | Joined: Feb 2018 Posts: 116 Shop Shark | | Shop Shark Joined: Feb 2018 Posts: 116 | It's a flip lever with a rod. Sorry, I didn't remember to take pictures when I saw it. I'll have some posted up soon.
Thanks for the help though! | | | | | Joined: Jul 2004 Posts: 2,987 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 2,987 | Sounds like a reverse lock out. | | | | | Joined: Jun 2018 Posts: 46 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2018 Posts: 46 | Probably a dumb question but are you sure the hi-low switch is in the dash? Would make more sense for the dash switch to be pto or something else.
Stuff I’m gonna work on, I swear
1963 C30 flatbed
1961 Apache 30 (parts, no title)
1960 GMC Big Bolt
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| | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy Fitzy440 and guys, it sounds like you are describing the reverse lockout lever that was on the sliding gear transmissions, those transmissions were used up to the 1947 model year, are you sure this truck is actually a 1948 model? | | | | | Joined: Feb 2018 Posts: 116 Shop Shark | | Shop Shark Joined: Feb 2018 Posts: 116 | That is what the owner said. The truck is partially covered in a junk pile so I haven't been able to get to the serial number. We are going to go back up this weekend and try to uncover it and get some pictures. Like I said, it is a parts truck. Not the best looking. | | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | I agree with 3B...sounds like the old Crash Box transmission with the lock out switch. Mike B | | | | | Joined: Feb 2018 Posts: 116 Shop Shark | | Shop Shark Joined: Feb 2018 Posts: 116 | | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 |
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Could be a 47.
In any case it's lockout for reverse on the older model transmission | | |
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