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| | | | Joined: Jul 2018 Posts: 80 Shop Shark | | Shop Shark Joined: Jul 2018 Posts: 80 | so i have what i'm pretty sure is a sm 420. there are a bunch of numbers cast into it. on the cover, GM6, 591588, on the side is j 1860 which i think is date code for oct 18 1960?
then under that, the number 3 and under that, 3761930. there is also the letter T stamped in the side. in addition, there is a spicer box coming out of what i think is a PTO on the side.
any help would be great.
thanks | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | | | | | | Joined: Jul 2018 Posts: 80 Shop Shark | | Shop Shark Joined: Jul 2018 Posts: 80 | yes, that did. so why is there the spicer box bolted to the drivers side of the tranny? i'm guessing that is a pto? would it have been used to run something off the truck? can i just remove it and find a cover for it?
thanks | | | | | Joined: May 2015 Posts: 11,028 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,028 | You can remove that PTO and get a cover for the opening. The bolt pattern has been the same for ages. I think I've seen new covers for $10, but you could browse the junkyard and probably find one off a dead tranny for next to nothing.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | Or just make one from a piece of flat stock metal. Mike B  | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | When you remove the PTO, label it as coming off a 420, otherwise it will be useless to someone who wants one. PTO's are very hard to identify if off the trans. Could even put # of teeth and pitch(straight or helix) of the drive gear on it.
Ed
Last edited by EdPruss; 01/14/2019 2:23 AM.
'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: Jul 2018 Posts: 80 Shop Shark | | Shop Shark Joined: Jul 2018 Posts: 80 | | | | | | Joined: Jul 2014 Posts: 1,289 Moderator for Tons o' Fun , Co-Moderator Driveline Forum | | Moderator for Tons o' Fun , Co-Moderator Driveline Forum Joined: Jul 2014 Posts: 1,289 | You can purchase a PTO cover from Novak (see tclederman's earlier post) . Its Novak part number K-PTO , list for $41.00 . Enjoy!
Ron - - Dusty53 1954 Chevy 3604In the Gallery Forum "You can't dance with the Devil and then wonder why you're still in Hell."
"They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel." | | | | | Joined: Oct 2017 Posts: 214 'Bolter | | 'Bolter Joined: Oct 2017 Posts: 214 | When you remove the PTO, label it as coming off a 420, otherwise it will be useless to someone who wants one. PTO's are very hard to identify if off the trans. Could even put # of teeth and pitch(straight or helix) of the drive gear on it.
Ed Are the PTO's sought after?
1953 Canadian GMC 9314 w/ (factory) Chevy 235
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | People with big trucks, in particular, might one one. If you have one, and you know what type/year transmission it came out of, post a Parts For Sale listing in the Swap Meet. | | | | | Joined: Oct 2017 Posts: 214 'Bolter | | 'Bolter Joined: Oct 2017 Posts: 214 | People with big trucks, in particular, might one one. If you have one, and you know what type/year transmission it came out of, post a Parts For Sale listing in the Swap Meet. I don't at the moment, I'm just waiting to hear back from the seller of an SM420 that has a PTO on it. I wouldn't want the PTO which is why I asked.
1953 Canadian GMC 9314 w/ (factory) Chevy 235
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Put a tag on the PTO - containing information (if available) about the transmission
- type of transmission
- vehicle type and year it came on/with
- year of the transmission (if you can ID that)
- any casting code/date on the transmission | | |
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