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| | | | Joined: May 2005 Posts: 227 'Bolter | | 'Bolter Joined: May 2005 Posts: 227 | Hey,
Might be a silly question...Someone asked what transmission was in my 1965 Chevy C30. I told him it was a 4-speed, top loader with the granny gear. He said no, what was the make or name of the transmission? I have no idea I said...
Does anyone here know?
1960 Chevy Apache (C10)
1965 Chevy C30 Dump Truck
1966 Chevy C30 Tow Truck
| | | | | Joined: Sep 2015 Posts: 81 'Bolter | | 'Bolter Joined: Sep 2015 Posts: 81 | If it's the original transmission, it's a Muncie SM-420.
Steve
1946 1/2 ton
| | | | | Joined: Dec 2015 Posts: 2,063 Big Bolt Forum Moderator | | Big Bolt Forum Moderator Joined: Dec 2015 Posts: 2,063 | | | | | | Joined: May 2005 Posts: 227 'Bolter | | 'Bolter Joined: May 2005 Posts: 227 | If it's the original transmission, it's a Muncie SM-420. Yes... it is the original.. Thank you for the info. I do need to get some work done including re-banding of the hand (parking) brake and would be nice to know the name of the transmission!
1960 Chevy Apache (C10)
1965 Chevy C30 Dump Truck
1966 Chevy C30 Tow Truck
| | | | | Joined: May 2005 Posts: 227 'Bolter | | 'Bolter Joined: May 2005 Posts: 227 | Great information!! Thanks!!
1960 Chevy Apache (C10)
1965 Chevy C30 Dump Truck
1966 Chevy C30 Tow Truck
| | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | Bornco That is a fine gearbox,tough,have 3 in service 2 spares waiting. | | | | | Joined: May 2005 Posts: 227 'Bolter | | 'Bolter Joined: May 2005 Posts: 227 | Bornco That is a fine gearbox,tough,have 3 in service 2 spares waiting. I agree! I have 2 with one waiting as well. The 65 is a dump truck and I fear it will need work soon because something is broken inside as I can loose 3rd when shifting like the shifter jumps out of track. You then have to push the clutch in find 2nd then try for 3rd again. Also the synchros are starting to go and it pops out of 2nd and sometimes 3rd. I have a transmission guy I trust (and need to ask before he retires) but fear the cost to rebuild. Would love to get it fixed before I go back to the original owner's family to show them the truck.
1960 Chevy Apache (C10)
1965 Chevy C30 Dump Truck
1966 Chevy C30 Tow Truck
| | | | | Joined: Jul 2000 Posts: 2,193 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,193 | I rebuilt my SM-420 recently. Lots of how to videos on the net. As your transmission is a later model, you should be able to get new syncros.
The thing is heavy! My brother could change a car transmission in 10 minutes. I don't think he could do that with a SM-420!
Gord 🇨🇦
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1954 1/2 ton 235 4 speed
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Heavy is only a relative term, 465 are slightly heavier, NP-540 series are heavier, Eaton 610 are even heavier, etc.
Ed
'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.
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