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| | | | Joined: Jan 2014 Posts: 3,690 'Bolter | | 'Bolter Joined: Jan 2014 Posts: 3,690 | My 51 truck has a later open diff that I have recently identified as the 55-62 1/2 truck rear (with the board’s help).
Anyway, it leaks from seemingly every orifice, but is pretty scabbed over and not dripping much at present. I will tear down and reseal but would like to just drive it as it is for the summer.
I would like to clean up the vent so that it can do it’s venting thing. Was there supposed to be a hose attached like a more modern diff vent would have?
1951 3100
| | | | | Joined: May 2015 Posts: 11,122 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: 11,122 | Usually vents of that era were just a fitting with a small cap over the top. But there's nothing stopping you from attaching a hose and extending the vent up to the frame.
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 2019 Posts: 119 'Bolter | | 'Bolter Joined: Mar 2019 Posts: 119 | Make sure that the vent is really venting. Over time dirt can build up in the cap and plug it. The cap should be free to "wiggle" on the stem that fits into the axle housing.
Rusty
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | If the vent is stopped up, it will force oil out any lower orifice every time it gets warm, until it is all gone.
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: Nov 2021 Posts: 1,258 'Bolter | | 'Bolter Joined: Nov 2021 Posts: 1,258 | You're lucky. My vent was completely gone when I got the truck. Not sure how long it was gone for, but I found rocks in the diff when I opened it and the oil may as well been tarsand.
I used a brass barbed fitting and pounded it in the hole. I am going to do a simple hose up to the frame with a coil to keep the dirt out. | | | | | Joined: May 2015 Posts: 11,122 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: 11,122 | You're lucky. My vent was completely gone when I got the truck. Not sure how long it was gone for, but I found rocks in the diff when I opened it and the oil may as well been tarsand.
I used a brass barbed fitting and pounded it in the hole. I am going to do a simple hose up to the frame with a coil to keep the dirt out. I've got that beat. Some previous owner put a pipe plug in place of the vent fitting. A guarantee of soaked brake shoes and gunk all over the differential. The hole should be threaded with 1/8" pipe threads.
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: Nov 2021 Posts: 1,258 'Bolter | | 'Bolter Joined: Nov 2021 Posts: 1,258 | Klhanson.
My hole was smooth. Thought about threading it, but then I saw the brass barb fitting at the hw store and said sold. | | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | JW51 If you put a hose on your vent need to fix it so muddobbers wont fill it up. Can screw a coarse stubby set screw in the hose so it can vent thru the threads. Or screen it somehow. | | |
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