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| | | | Joined: Feb 2003 Posts: 1,377 'Bolter | | 'Bolter Joined: Feb 2003 Posts: 1,377 | Just wondering if 2 speed rear ends and a 5 speed trans with o/d were available back in 37. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | If you find a two speed rear axle, the ratios will be 'slow and slower' which is not very useful. Modern rear axles with the correct wheel bolt pattern and modern 'trans will be useful at modern speeds, depending on your plans.
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.
| | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | The 1937 truck transmission was a 4-speed, that was all they offered back then. I believe 1939 was the first year Chevrolet offered a 2-speed rear (mechanical shift). I don't think Chevrolet put an OD transmission in a BIG truck until sometime in the early 1960's. Mike B  | | | | | Joined: Feb 2003 Posts: 1,377 'Bolter | | 'Bolter Joined: Feb 2003 Posts: 1,377 | I was just curious if those were available back then,would love to have a 37 big truck but would probably be too slow for me. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Depending on your engine, etc., an NP-4500 will bolt up to most anything, parts are available. Larger (Spicer 5553A) etc. are also available, both good OD trans.' A Brownie aux. trans' is also an option. If you have torque tube, it would be easier to convert to open driveline.
Your '37, you didn't say what size, can handle modern running gear, power steering, power brakes, wheels, while keeping sheet metal original.
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.
| | | | | Joined: Feb 2003 Posts: 1,377 'Bolter | | 'Bolter Joined: Feb 2003 Posts: 1,377 | If I ever build one it will be with a 261 and a trans with o/d and maybe a two speed rear. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | GMC 302's wiil also provide adequate power.
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.
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | GMC 302's wiil also provide adequate power.
Ed Would it fit OK with the original Chevrolet truck radiator placement? | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | GMC engines are about 3" longer than Chevy engines. Many on here have fit GMC engines in Chevy trucks, however.
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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