diff fluid change...How to?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Easy, really.... you will need a small hand pump (I recommend the mighty-mite from Pepboys (about 10.00); a floor jack and jack stands; waste oil bin; assistant to hold hoses (just easier); big-assed pipe wrench.
1) raise car
2) crawl under car with big-assed pipewrench. On the passengers side of the diff, you will see a bolt with a tag on it. THAT is the target. Apply the big-assed pipewrench to the bolt and turn. You see, the bolt is tight, and space is limited, the big-assed pipewrench is quick and space efficient.
3) Using pump, remove all the old fluid.
4) Using pump, pour in 2 bottles of GM Differencial Additive. Yes, 2 bottles. That is the recomendation of Gordon Killebrew.
5) Top off with standard 75-90 gear oil (I think that's it, don't remember for sure, but it's something like that). when the oil starts dripping out, you know its about full.
6) reinstall bolt using big-assed pipewrench.
7) lower car, done.
I can do this in about 20 minutes. No kidding.
1) raise car
2) crawl under car with big-assed pipewrench. On the passengers side of the diff, you will see a bolt with a tag on it. THAT is the target. Apply the big-assed pipewrench to the bolt and turn. You see, the bolt is tight, and space is limited, the big-assed pipewrench is quick and space efficient.
3) Using pump, remove all the old fluid.
4) Using pump, pour in 2 bottles of GM Differencial Additive. Yes, 2 bottles. That is the recomendation of Gordon Killebrew.
5) Top off with standard 75-90 gear oil (I think that's it, don't remember for sure, but it's something like that). when the oil starts dripping out, you know its about full.
6) reinstall bolt using big-assed pipewrench.
7) lower car, done.
I can do this in about 20 minutes. No kidding.
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From: Almost all Skyline Cruises Vettes at Waterside 1-5
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Originally Posted by bogus
Easy, really.... you will need a small hand pump (I recommend the mighty-mite from Pepboys (about 10.00); a floor jack and jack stands; waste oil bin; assistant to hold hoses (just easier); big-assed pipe wrench.
1) raise car
2) crawl under car with big-assed pipewrench. On the passengers side of the diff, you will see a bolt with a tag on it. THAT is the target. Apply the big-assed pipewrench to the bolt and turn. You see, the bolt is tight, and space is limited, the big-assed pipewrench is quick and space efficient.
3) Using pump, remove all the old fluid.
4) Using pump, pour in 2 bottles of GM Differencial Additive. Yes, 2 bottles. That is the recomendation of Gordon Killebrew.
5) Top off with standard 75-90 gear oil (I think that's it, don't remember for sure, but it's something like that). when the oil starts dripping out, you know its about full.
6) reinstall bolt using big-assed pipewrench.
7) lower car, done.
I can do this in about 20 minutes. No kidding.
1) raise car
2) crawl under car with big-assed pipewrench. On the passengers side of the diff, you will see a bolt with a tag on it. THAT is the target. Apply the big-assed pipewrench to the bolt and turn. You see, the bolt is tight, and space is limited, the big-assed pipewrench is quick and space efficient.
3) Using pump, remove all the old fluid.
4) Using pump, pour in 2 bottles of GM Differencial Additive. Yes, 2 bottles. That is the recomendation of Gordon Killebrew.
5) Top off with standard 75-90 gear oil (I think that's it, don't remember for sure, but it's something like that). when the oil starts dripping out, you know its about full.
6) reinstall bolt using big-assed pipewrench.
7) lower car, done.
I can do this in about 20 minutes. No kidding.
On my 88 a standard Allen wrench removes and reinstalls the plug easily
seeya
Race Director
Joined: Jan 2002
Posts: 12,261
Likes: 85
From: O'Fallon Missouri
Originally Posted by jackdaroofer
When did GM change from an Allen wrench fitting to a pipe fitting on the diff? Just curious!
On my 88 a standard Allen wrench removes and reinstalls the plug easily
seeya
On my 88 a standard Allen wrench removes and reinstalls the plug easily
seeya
Don't screw up the diff plug with a pipe wrench, when it is designed to be removed with an allen wrench.
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
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You could still use a breaker bar (i.e. section of metal pipe) over the proper allen wrench and have the best of both worlds. That's how I removed my knock sensors using a box-ended wrench...
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