Drain Plug for diff.
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
There is no drain plug. To empty the oil you need to use a suction device to pull it out of the fill / level plug on the side of the diff. You can get most of it out that way.
Race Director
Joined: Apr 2011
Posts: 11,183
Likes: 3,335
From: North of Toronto - Ontario
5/8 square (8 point) (at least on the iron diff it is) what year is your car?
M
FWIW, one of those stupid multi-sockets (gator grip) will usually work if you can't find an 8pt, also can kind of get in there with a crowsfoot once you remove the passenger tire
M
M
FWIW, one of those stupid multi-sockets (gator grip) will usually work if you can't find an 8pt, also can kind of get in there with a crowsfoot once you remove the passenger tire
M
Last edited by Mooser; Mar 26, 2020 at 02:09 PM.
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Thread Starter
Instructor
Joined: May 2018
Posts: 116
Likes: 14
its a 79, 5/8 8 pt. sounds about right
Thread Starter
Instructor
Joined: May 2018
Posts: 116
Likes: 14
Race Director
Joined: Oct 2000
Posts: 17,102
Likes: 7
From: Fair Oaks, OK
Unless your car has seen nothing but harsh conditions for 40 years, the spare carrier is a breeze to remove. Getting it out of there will make the job a lot easier.
Thread Starter
Instructor
Joined: May 2018
Posts: 116
Likes: 14
Thread Starter
Instructor
Joined: May 2018
Posts: 116
Likes: 14
No i am not a points guy, and i had no idea how long the spare has been in place, also i do not intend on using it either (AAA). Initially when i had this brain storm of an idea to drain out the old and replace with new, i was under the impression it would a be simple extraction and refill, however i am discovering that i do not own an 8 pt. socket, and i must remove the spare if i don't. So i sprayed the spare tire hold down with PB blaster, and pray i dont strip the threads on anything. i will keep you posted either way.
Race Director
Joined: Apr 2011
Posts: 11,183
Likes: 3,335
From: North of Toronto - Ontario
not sure where you're located (consider adding your car year and at least rough location to your info) but if there's a harbor freight nearby they should have something called spline sockets, they will (should) work on square bolts, or check with a farm/tractor place, lots of old stuff had square head lag bolts
With the socket you just need to pull the passenger tire which you pretty much need to do to fill it anyway.
And if I may, when you go to fill it back up, run a needle through the bottle/hose that gets stuck into the diff, prevents it from accidentally falling inside
M
With the socket you just need to pull the passenger tire which you pretty much need to do to fill it anyway.
And if I may, when you go to fill it back up, run a needle through the bottle/hose that gets stuck into the diff, prevents it from accidentally falling inside
M
Race Director
Joined: Mar 2016
Posts: 14,351
Likes: 8,162
From: Napa Valley California
This is why I had a drain plug drilled and tapped into the housing when I had the center section built.
There have been a few threads from forum members who drilled and tapped a drain hole in their diff's with it still in the car.
Run a search, because it can be done.
Good luck!
There have been a few threads from forum members who drilled and tapped a drain hole in their diff's with it still in the car.
Run a search, because it can be done.
Good luck!
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
I found it rather easy to remove/replace the differential oil in my '79. I just used an open-end wrench to remove the square plug. It removed rather easily. Had it been frozen I would have just used some big slip-joint pliers as it's an easily replaceable part. If I recall properly it is standard a black iron plug with tapered (pipe) threads. You remove with a "transfer pump". They're cheap and easy to find.
The old oil will be utterly vile smelling and you WILL get some on you. Wear clothes you consider disposable as the smell lingers after washing(s).
Make sure you have the car fully raised. If you only lift the rear you will overfill as the proper level is even with the bottom of the fill hole. In the vein have some rags handy to immediately cover the fill hole when you remove the plug in the event it was previously over filled. If it was and you don't you will have a nasty, hideous smelling mess
The old oil will be utterly vile smelling and you WILL get some on you. Wear clothes you consider disposable as the smell lingers after washing(s).
Make sure you have the car fully raised. If you only lift the rear you will overfill as the proper level is even with the bottom of the fill hole. In the vein have some rags handy to immediately cover the fill hole when you remove the plug in the event it was previously over filled. If it was and you don't you will have a nasty, hideous smelling mess
Last edited by SwampeastMike; Mar 29, 2020 at 06:20 PM.
