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| | | | Joined: Jan 2020 Posts: 431 'Bolter | | 'Bolter Joined: Jan 2020 Posts: 431 | I see a square plug on the rear differential, I'm guessing that's how I drain it. My questions are:
1. What oil type goes in it
2. Is there a fill cap on the top somewhere?
Thanks! | | | | | Joined: Feb 2019 Posts: 4,512 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,512 | The plug your seeing is for filling. You drain it by loosening and prying open the bottom of the cover. Once drained, remover the cover, clean out the gunk on the bottom. Inspect or replace the gasket , then reinstall the cover.
Fill to the bottom of the fill hole. I use 90 weight multi-purpose gear lubricant. If you have a posi rear I believe you will also need some type of additive.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | | | | Joined: May 2015 Posts: 11,164 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: 11,164 | You MAY be able to drain the differential by removing the lowest bolt from the cover. That works on a 47-55.1 1/2 ton. If that works, there's no need to mess with the cover gasket.
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: Jan 2020 Posts: 431 'Bolter | | 'Bolter Joined: Jan 2020 Posts: 431 | Thanks, guys! Isn't there some letter/number combo on the differential to tell me if it's a posi? Or do I have to just jack the thing up? Dang Frankenstein projects  | | | | | Joined: Feb 2019 Posts: 4,512 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,512 | Or do I have to just jack the thing up? That would certainly be the easiest way to tell. If you can find some numbers on the rear, post them and I’m sure our collective will be able to tell you what you have.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | | | | Joined: Jan 2020 Posts: 431 'Bolter | | 'Bolter Joined: Jan 2020 Posts: 431 | That would certainly be the easiest way to tell. If you can find some numbers on the rear, post them and I’m sure our collective will be able to tell you what you have. Will do- thanks! | | | | | Joined: Jan 2020 Posts: 431 'Bolter | | 'Bolter Joined: Jan 2020 Posts: 431 | I ran out and quickly checked the sides of the carrier, no numbers found yet but on the left (driver) side are 3 horizontal lines, and on the right (passenger) side are 3 vertical lines. I'm going to look at the base of it within the hour. | | | | | Joined: Jan 2020 Posts: 431 'Bolter | | 'Bolter Joined: Jan 2020 Posts: 431 | Can't see the numbers. I'll have to wait until after work when I can get some grungies on. | | |
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