Quick ?: Differential Fluid
Thread Starter
Melting Slicks
Joined: Sep 2002
Posts: 2,783
Likes: 2
From: Engineers do it better.
Quick ?: Differential Fluid
Is there a drain plug for rear end (1974: 3.08)? Or do I have to remove the cover. It does not leak so I don’t want to remove it. I was thinking if there is no drain plug, then I will just pump it out with a drill operated pump. Sound OK? Do I have to remove the spare tire to do this?
How much fluid/additive is required? 3 bottles of fluid and one bottle of additive? I am planning on sticking with what the General ordered.
Thanks in advance.
:cheers:
How much fluid/additive is required? 3 bottles of fluid and one bottle of additive? I am planning on sticking with what the General ordered.
Thanks in advance.
:cheers:
Drifting
Joined: Mar 2001
Posts: 1,411
Likes: 2
From: St. Louis, Missouri
Re: Quick ?: Differential Fluid (desi)
I used a cheap hand pump to drain mine. Removing the spare tire makes it easier to access the drain plug plus, it would be a good time to check out the tire anyway.
Instructor
Joined: Jun 2001
Posts: 174
Likes: 3
From: Ann Arbor MI
Re: Quick ?: Differential Fluid (Neo Fender)
I just changed the dif fluid on my '76. The plug was really easy to access by removing the rear passenger-side wheel. A $12 suction pump works really well to drain and fill.
Brian
Brian
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: Quick ?: Differential Fluid (desi)
I got to it without removing hte spare tire, but it was a tight squeeze...the plug is at the rear passenger side...mine had an orange triangular warning tag on it. I used the pump that I use to pump oil into it by attaching a longer hose to the end of it and sliding it up into the diff. I think it's 3oz of additive to the 80W-90 gear oil. I think mine took just over 2 quarts of oil. I mixed the additive up with the oil first by squeezing the entire tube into an empty quart bottle and added oil, then closed the cap and shook it up real good...just to evenly distribute the additive instead of waiting the first few miles before I can see if the tires still smoke :)
Melting Slicks
Joined: Jul 2002
Posts: 3,128
Likes: 3
From: Deltona (son of Deland and DAYTONA) FL
Re: Quick ?: Differential Fluid (desi)
I just did mine last weekend. Tookout he spare tire carrier, made it easier to get to the drain plug. It took just under 2 quarts of gear oil and one bottle of the GM addititive. I used a manual pump that is used for sucking the ooil through the dipstick on marine engines.
Racer
Joined: Feb 2001
Posts: 330
Likes: 0
From: Baja Oregon
Re: Quick ?: Differential Fluid (desi)
Thanks for the info guys....gotta luv this forum.
How about synthetic fluid? Any pros/cons?
Thanks again.
How about synthetic fluid? Any pros/cons?
Thanks again.
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Safety Car
Joined: Apr 2001
Posts: 3,581
Likes: 28
From: Spring, Texas
Re: Quick ?: Differential Fluid (desi)
Like most others above, I used a pump to extract the old fluid. My spare tire and cover were removed as well. It took 2 bottles of GM fluid + 1 bottle of additive.
Race Director
Joined: Mar 1999
Posts: 10,258
Likes: 1
From: Calif.
Re: Quick ?: Differential Fluid (desi)
[DEVO]You must pump it.[/DEVO]
I use a 4 oz. tube of a product called Equa Torque. It meets GM spec for posi additive and it's often available right off the rack in many parts stores. Then just pump in the 80W90 gear oil until it seeps out the bottom of the fill hole. Go for an easy ride around the block to mix it all up and you're golden.
I use a 4 oz. tube of a product called Equa Torque. It meets GM spec for posi additive and it's often available right off the rack in many parts stores. Then just pump in the 80W90 gear oil until it seeps out the bottom of the fill hole. Go for an easy ride around the block to mix it all up and you're golden.
Race Director
Joined: Mar 1999
Posts: 10,258
Likes: 1
From: Calif.
Re: Quick ?: Differential Fluid (Dwayne 76)
You're probably OK if it's not making noise. I don't know whether there's a recommended service interval. I do mine every couple of years. Why? I like the smell of gear oil. :D
Racer
Joined: May 1999
Posts: 268
Likes: 1
From: CT
Re: Quick ?: Differential Fluid (desi)
one bottle of additive should take care of it. You can put more in later though if its necesary, just be sure to drain some out first.
If you use synthetic fluid you shouldnt need any of the additive. Most synthetics are designed to work without it.
If you use synthetic fluid you shouldnt need any of the additive. Most synthetics are designed to work without it.
Melting Slicks
Joined: Oct 2000
Posts: 3,023
Likes: 2
From: TEXASTEXASTEXASTEXAS TEXASTEXASTEXASTEXAS
St. Jude Contributor
Re: Quick ?: Differential Fluid (71vettman)
Call me a lazy bastard, but this is one job I leave for the quicky-lube. Old diff fluid is nasty, smelly stuff and they suck it out for me and replace it with my Mobil 1 for $12. Money well spent, IMHO.
JB
JB
