Changing Differential Oil...
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Le Mans Master
Joined: Mar 2006
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From: E. Amherst NY
Changing Differential Oil...
'86 L98, D36. I want to change the gear oil in the rear end before the drag strip opens back up.
Instead of dropping the differential to drain it, I was hoping to use my vacuum oil changer I use for the boat. Planned on going in through the oil level screw and sucking it dry. Anybody done this before?
Instead of dropping the differential to drain it, I was hoping to use my vacuum oil changer I use for the boat. Planned on going in through the oil level screw and sucking it dry. Anybody done this before?
Le Mans Master
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I know people have recommended sucking it out, I personally just drilled a hole in the bottom and tapped it then plugged it. The vacuum method should work though. Just make sure you get the hose as low as it can go to get as much of the old oil out as you can.
Team Owner
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From: Lacey WA RVN 68-69
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Sucking the old fluid out is the best way. Unless you are sure where to drill, it can be a big "Oh S***!" if you drill in the wrong place 
.
The accessory catalogs used to carry a kit to install a drain plug and came with a template to show exactly where to drill. Don't know if they are still offered, but you can get 95% of the old fluid out even by using one of the Harbor Freight $5 hand pumps. And you use the same pump to put the new fluid in along with the GM additive.
.The accessory catalogs used to carry a kit to install a drain plug and came with a template to show exactly where to drill. Don't know if they are still offered, but you can get 95% of the old fluid out even by using one of the Harbor Freight $5 hand pumps. And you use the same pump to put the new fluid in along with the GM additive.
Thread Starter
Le Mans Master
Joined: Mar 2006
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From: E. Amherst NY
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I used a fluid pump I got from Harbor Freight Tools. It attaches to a 1/4 inch drill. Similar to the ones they carry in the J.C. Whitney Catalogs. Works well and it's reversible, too. 
http://www.jcwhitney.com/Auto-Parts/...FQETGgodXWjN5g
http://www.jcwhitney.com/Auto-Parts/...FQETGgodXWjN5g