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| | | | Joined: Jun 2017 Posts: 370 Shop Shark | | Shop Shark Joined: Jun 2017 Posts: 370 | I have a 1949 3600 with a SM 420 4 speed transmission.
How much gear oil does it take? Should it be filled to the fill hole?
Thanks Don
Can’t begin to tell you how much I hate the name Stovebolt.
| | | | | Joined: Feb 2004 Posts: 29,818 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,818 | With the vehicle parked on a level floor the oil should come to the bottom of the fill hole. That places the level just below the centerline of the input/output shafts and prevents leakage out of either end. The rotation of the gears (especially the big bull gear for 1st.) circulates the lube inside the case.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 1995 Posts: 5,723 24601 | | 24601 Joined: Nov 1995 Posts: 5,723 |
~ John A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult. 1949 Chevrolet 3804In the Legacy Gallery | In the Gallery Forum1973 IH 1310 Dump1963 Kaiser M38A12001 International/AmTran RE3000 "Skoolie"2014 Ford E-350 4x4 (Quigley) | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | For checking the fluid level: "With unit/transmission at operating temperature the lubricant should be level with the bottom of the filler plug hole [on the side of the transmission]."
"If the lubricant level is checked with the unit/transmission cold, the lubricant level should be 1/2" below the filler plug hole [on the side of the transmission]."
If you are filling a warm transmission after draining (many people do that, thinking/hoping the thinner oil will drain out better), use your judgement - I still fill to about 1/2 in below the filler hole on the side of the transmission, and then drive it and then check it after the drive. | | | | | Joined: Jan 2002 Posts: 2,841 'Bolter | | 'Bolter Joined: Jan 2002 Posts: 2,841 | I stick my index finger in the hole, then slightly bend the finger downward then back up. Check it. If I find some oil on the tip of my index finger, I'm good......well the truck is good. I find that filling it til it runs out the fill hole is just a little too much oil.
Craig My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
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