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| | | | Joined: Jan 2013 Posts: 1,518 'Bolter | | 'Bolter Joined: Jan 2013 Posts: 1,518 | Wondering why there is a rear seal listed for torque tube applications? Can anyone shed any light on this? Is it to control the amount of oil spilling over the seal to the front u-joint enclosure?
Trying to wrap my head around this.
Thanks in advance,
Steve
1953 Chevrolet 3100261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY GalleryVideo of the 261 running1964 GMC 1000305 Big Block V6, sm420, the next cab off restoration
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | | | | | | Joined: Jan 2013 Posts: 1,518 'Bolter | | 'Bolter Joined: Jan 2013 Posts: 1,518 | I've seen that in the manual Tim. The sm420 has a seal in the transmission around the main shaft in front of the input yoke and I dont know why or what purpose it holds.
1953 Chevrolet 3100261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY GalleryVideo of the 261 running1964 GMC 1000305 Big Block V6, sm420, the next cab off restoration
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Sorry, sstock,
I have used a few open driveshaft SM420s in/on torque-tube trucks. I have "converted" open driveshaft SM420s to torque-tubes. I'd have to see a photo of what you are referring-to?
Maybe someone else will be helpful? | | | | | Joined: Jan 2013 Posts: 1,518 'Bolter | | 'Bolter Joined: Jan 2013 Posts: 1,518 |
Last edited by sstock; 01/20/2018 12:11 AM.
1953 Chevrolet 3100261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY GalleryVideo of the 261 running1964 GMC 1000305 Big Block V6, sm420, the next cab off restoration
| | | | | Joined: Mar 2011 Posts: 1,146 Shop Shark | | Shop Shark Joined: Mar 2011 Posts: 1,146 | This Rear bearing retainer uses the oil seal. That rear bearing retainer was/is used on 3/4 ton and 1 ton open drive shaft trucks. Here is a Picture of SM420 4 speed with a closed drive shaft (torque Tube) rear bearing retainer used on 1/2 ton trucks. No need for oil seal. The link http://chevy.oldcarmanualproject.com/parts/1929_54/220.htm you provided is showing a open drive shaft rear bearing retainer. | | | | | Joined: Jan 2013 Posts: 1,518 'Bolter | | 'Bolter Joined: Jan 2013 Posts: 1,518 | Thanks Jorb for you shedding light on this, I suspected this but had to be sure.
1953 Chevrolet 3100261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY GalleryVideo of the 261 running1964 GMC 1000305 Big Block V6, sm420, the next cab off restoration
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