The hand pump method is very easy. I wouldn't spend the time or money to add a drain.
Diff Drain
Thread Starter
Pro
Joined: Jan 2005
Posts: 686
Likes: 62
From: San Jose Ca
Diff Drain
What's the current favored method to add a drain to the D44? I've got it out for a gear swap and want to be able to service it. I'm aware of the 1/8" drain between the pipes and I remember someone talking about intersecting the bottom cover bolt as an option too. Has anyone put a pipe plug in the cover instead? Does anyone have an opinion?
Scott
Scott
Last edited by MaxLean; Jan 18, 2008 at 01:57 AM.
Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
corvette clinic in sanford FL used to offer a "kit"...all it really was, was a template to make sure you drill the hole in the right place...it also had a tap and the right plug...see if they are still open...ask for chris.
and it STILL amazes me that GM didn't put a drain plug on it....come on...REALLY? no one ever believes me when i tell them there is no good way to service it.
and it STILL amazes me that GM didn't put a drain plug on it....come on...REALLY? no one ever believes me when i tell them there is no good way to service it.
Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
...but i wouldn't call that a "good" way to service it...you never really get all the gunk out of the bottom of the diff. i mean, imagine if you had to change the motor oil by hand pumping the old stuff out of the dipstick tube.
Instructor
Joined: Jul 2007
Posts: 181
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From: Boise ID
Go to a boat supply place like overtons or your local boat place they should have an electric pump that boaters use to suck the oil up from the dipstick tube they cost around $35. it takes about 10 minutes to suck the grease out of the diff and you can poke around inside the diff to get most of the crap out. Thats what I use. P.S. if it's cold drive it around for 15 or 20 minutes to get the grease warm so it will pump out faster and easier 
Instructor
Joined: Jul 2007
Posts: 181
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From: Boise ID
Instructor
Joined: Sep 2002
Posts: 105
Likes: 0
From: Orlando Florida
Since it is off the car, drill and tap in the correct location (not sure where that is) would be best.
I use a siphon pump from Home Depot hooked to a 3/8" drill to drain the fluid. The pump is about hand size and has a chuck end for connection to a drill motor. I installed clear tubing on each end (inlet/outlet) of the pump. You can make the tubing as long as you want to make things easier on yourself while doing this. Put the inlet end of tubing into the fill port and place the outlet tube into a drain pan.
I then use a cheap garden sprayer as a fill device. I modified the outlet tip by cutting off the spray nozzle and installing some clear plastic tubing (also from Home Depot) to the spray wand at the tip. I used zip ties to secure the clear tubing.
Then simply fill the sprayer with the lube of your choice (I use Mobil 1), pump up the sprayer and squeeze the handle. The clear tubing is to allow you to put the tube completely inside the differential and minimize spills. Clear tubing lets you see the fluid flow to ensure things are going OK.
This works good for manual trannys as well.
Later ... Larry S.
I use a siphon pump from Home Depot hooked to a 3/8" drill to drain the fluid. The pump is about hand size and has a chuck end for connection to a drill motor. I installed clear tubing on each end (inlet/outlet) of the pump. You can make the tubing as long as you want to make things easier on yourself while doing this. Put the inlet end of tubing into the fill port and place the outlet tube into a drain pan.
I then use a cheap garden sprayer as a fill device. I modified the outlet tip by cutting off the spray nozzle and installing some clear plastic tubing (also from Home Depot) to the spray wand at the tip. I used zip ties to secure the clear tubing.
Then simply fill the sprayer with the lube of your choice (I use Mobil 1), pump up the sprayer and squeeze the handle. The clear tubing is to allow you to put the tube completely inside the differential and minimize spills. Clear tubing lets you see the fluid flow to ensure things are going OK.
This works good for manual trannys as well.
Later ... Larry S.
Le Mans Master
Joined: Apr 2005
Posts: 6,413
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From: The Old Dominion
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Drifting
Joined: Jul 2003
Posts: 1,613
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From: Orlando FL
of course, but i still say its not the easiest way to do it...its not wrong, but not the best way...all i'm saying is that i would never imagine a tub designer making a bathtub that you had to empty by pumping the used water into the sink 
would it have killed GM to put a drain plug of the diff?
would it have killed GM to put a drain plug of the diff?
Drifting
Joined: Dec 2005
Posts: 1,313
Likes: 2
From: High Ridge Missouri
I installed the drain plug kit in my diff and am happy with it. The drill bit and tap included have washers welded at specific depths so you don't go to deep and damage your ring gear, but I guess if your doing this on the diff that's disassembled it doesn't matter.
By the way if anyone is interested in this they can have it for a few bucks you just have to locate a drain plug to go with it.
By the way if anyone is interested in this they can have it for a few bucks you just have to locate a drain plug to go with it.
Burning Brakes
Joined: Jun 2005
Posts: 1,188
Likes: 13
From: Wallingford Vermont
I added a drain to my diff years ago when I changed gears. I think I used a drain plug from an old oil pan (magnetic) . Figured a good spot on the cover that cleared the ring gear, then drilled and taped (NPT).
I know NAPA used to sell a kit for AT oil pans.
Trust me, this is alot easier than trying to suck out the old fluid . If you got the cover off there's no reason not to do it!
I know NAPA used to sell a kit for AT oil pans.
Trust me, this is alot easier than trying to suck out the old fluid . If you got the cover off there's no reason not to do it!
Thread Starter
Pro
Joined: Jan 2005
Posts: 686
Likes: 62
From: San Jose Ca
Well, thanks for all the advice guys! I ended up drilling and tapping for a 1/4" pipe plug just beneath the ring gear on the meaty part of the case just ahead of the flange. Looks like it'll work pretty well (it's bigger than the 1/8" plug that comes in that kit), but it's right above the left exhaust pipe! I'll have to drop the exhaust slightly to access it, but it's no biggie.
Scott
I ended up drilling and tapping for a 1/4" pipe plug just beneath the ring gear on the meaty part of the case just ahead of the flange. Looks like it'll work pretty well (it's bigger than the 1/8" plug that comes in that kit), but it's right above the left exhaust pipe! I'll have to drop the exhaust slightly to access it, but it's no biggie. Scott
Slingshot
Joined: Dec 2001
Posts: 3,817
Likes: 24
From: Charlotte NC
I installed the drain plug kit in my diff and am happy with it. The drill bit and tap included have washers welded at specific depths so you don't go to deep and damage your ring gear, but I guess if your doing this on the diff that's disassembled it doesn't matter.
By the way if anyone is interested in this they can have it for a few bucks you just have to locate a drain plug to go with it.
By the way if anyone is interested in this they can have it for a few bucks you just have to locate a drain plug to go with it.
