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| | | | Joined: May 2009 Posts: 15 New Guy | | New Guy Joined: May 2009 Posts: 15 | I was replacing the carpet in my 1955 3100 and noticed that there was a slot for a 4x4 right above the manual trans shifter. I have 3100 emblems on the truck, it has a 4spd compound low tranny. My question is this a 4x4 that was modified or were all the cabs made with this slot? | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy SANJOSE55, if the slot you are talking about is to the right side of the shifter, it is probably a slot for a parking brake lever from a larger truck that had a propeller shaft parking brake, someone probably replaced the transmission cover plate with one from a larger truck. I think factory 4X4s started in 57, but I may be wrong about that. | | | | | Joined: May 2009 Posts: 15 New Guy | | New Guy Joined: May 2009 Posts: 15 | Thanks,
But the slot is to the left of the trans shifter. And the gallery had a 1955 4x4? The hole is NOT in the trans case, buy in the cab? | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | no one really knows exactly when GM started doing the NAPCO conversions themselves, late 50's sometime, the earlier ones [54+] were done at a 3rd party shop, sometimes a GM dealer .... there is no "slot" above the floor shift in any TF model, the 4x4 lever was to the right of the shifter, like so, no tellin over 50 years who modified yours, might have been for a winch control or a dump bed | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | You said "above", then said "left". There can be a foot starter hole, trans brake hole, previous owner holes, and brake fill hole. The 4 x 4 is not in the area you describe. Ist year for open drive shaft, don't think any factory 4 X 4 in that year. Is it a factory looking punch hole or a hack job hole? Like Red says, lotta owner add-ons like home made snow plow blade lift, aftermarket throttle linkage holes, oops! wrong place holes, etc. To be specific: No NAPCO 1/2T until 55 when open drive shaft started in them, before that 3/4 and larger had NAPCO. No one knows exactly when the 3/4 and up started. In 1955 Napco sold a kit to dealers for adding 4X4 to 1/2T.(only four holes needed to be drilled)the factory built 4 X 4's using NAPCO were 1956 for GMC and 1957 (as stated) for Chevy. GM redesigned their chassis in 60 with coil front on 2WD and leafs on 4WD and designed their own 4X4 system, albeit, still had devorced Xfer case like NAPCO. I think they used Rockwell xfer cases then NP 205..... But basically, no more NAPCO, Napco sold out to Dana which is Spicer.
Last edited by bartamos; 07/30/2009 12:36 AM.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Feb 2007 Posts: 513 Shop Shark | | Shop Shark Joined: Feb 2007 Posts: 513 | could it of been for a pto?
1949 Chevy 3600 Flatbed all orginal 1964 gmc 4000 1973 gmc 6000 2005 chevy duramax 4x4 1994 chevy 1500 Trucks are GM and Tractors are Orange "I don't measure a man's success by how high he climbs but how high he bounces when he hits bottom." - General George S. Patton | | |
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