Differential fill plug ---help please
Thread Starter
Pro
Joined: Mar 2004
Posts: 584
Likes: 0
From: Okemos MI
Differential fill plug ---help please
I am looking for suggestions for removing my differential fill plug.
For anyone that has done this you know how tight the space is to work. I can't get a wrench on it. I have removed this square plug in the past with a 12 point 5/8" socket.
Not this time! the corners of the square are rounded enough that I cant get enough torque on it before it slips off. This time its really really tight.
I also tried a crescent wrench from the over the top and used a ratchet extension (in the hole at the end) to turn the wrench but it wont budge (cant get much torque on it)
I used penetrating oil, vibration and heated the diff case, still no luck...
Does anyone have any creative suggestions to remove this square plug.
is there such a thing as a square socket? or a specialty tool that will work?
Sears makes a "gator grips universal socket" anyone had any luck with that?
Thanks for you help..
John
For anyone that has done this you know how tight the space is to work. I can't get a wrench on it. I have removed this square plug in the past with a 12 point 5/8" socket.
Not this time! the corners of the square are rounded enough that I cant get enough torque on it before it slips off. This time its really really tight.
I also tried a crescent wrench from the over the top and used a ratchet extension (in the hole at the end) to turn the wrench but it wont budge (cant get much torque on it)
I used penetrating oil, vibration and heated the diff case, still no luck...
Does anyone have any creative suggestions to remove this square plug.
is there such a thing as a square socket? or a specialty tool that will work?
Sears makes a "gator grips universal socket" anyone had any luck with that?
Thanks for you help..
John
Last edited by Lotus76; Aug 22, 2009 at 06:42 PM. Reason: wrong socket size
Melting Slicks
Joined: Jul 2006
Posts: 2,285
Likes: 487
From: Salmon Arm, BC
I hate to tell you this.....I tried all of the above recommendations with no luck. I ended up pulling the rearend - drilling out the plug breaking some easyouts - drilling the plug out some more and eventually using a hammer and chisel to break apart the remaining plug...what a PIA
I had to get a pipe tap to chase the hole after as some damage was done to the threads.
While I was in there I looked over my rearend and discovered some badly worn parts - that led to a partial rebuild.
This all started by me changing the pinion seal......so be prepared
I had to get a pipe tap to chase the hole after as some damage was done to the threads.
While I was in there I looked over my rearend and discovered some badly worn parts - that led to a partial rebuild.
This all started by me changing the pinion seal......so be prepared
Tech Contributor
Joined: Aug 1999
Posts: 15,154
Likes: 3,959
From: Connecticut, USA
That plug is a 3/4" npt thread. Usually the 8 pt sockets work. If not hit it with a little propane and PB blaster and let it soak into the threads and try again. When I change the rear oil I just jack up the RH side on a small jack stand, slide under and remove the drain plug I installed, use the 5/8 socket and pump in fresh 80-145 Lucas.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Here's what I use and I've never rounded one or failed to get one loose. Its an Apex 5620 5/8"
http://westsidedelivers.com/previewi...odtype=product
http://westsidedelivers.com/previewi...odtype=product
Thread Starter
Pro
Joined: Mar 2004
Posts: 584
Likes: 0
From: Okemos MI
I got a 8 point 5/8" at sears and it worked GREAT! 
I need a new fill plug for next time...corners were pretty rounded. I put some anti seize on so I can get it apart easy next time.
Thanks for the help.
John
I need a new fill plug for next time...corners were pretty rounded. I put some anti seize on so I can get it apart easy next time.
Thanks for the help.
John
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