Differential fill plug frozen - I need help

[David Schwarz]

I'm trying to change out the lubricant, but I can't get the bloody fill plug out. I don't want to proceed until I do. I'm pretty sure I have the correct location, but maybe I don't. What I'm trying to loosen is on the face of the differential facing the front of the car, about half-way up, on the drivers side. The only tool I can fit in the square hole is the drive for a 3/8" wrench. I've sprayed a couple of times with WD-40 and I'm about to go down and try again (waited about 20 min. now). Am I missing something here, I'm afraid to torque much harder for fear of stripping out the square hole

 

[what_stanger?]

yes, thats the fill hole..... retarded huh?

you could try some PB blaster, or try putting more pressure on the wrench...

but if you're really afraid of that, you can get a new differential cover/girdle that fills and drains through the cover......

 

[67390GTA]

If you can strip out the 3/8 drive on that plug then you are one hell of a man...you could try heating the thing up with a torch or by driving the car around. Just pull like a mofo on that ratchet or put a nice big breaker bar on it and pull like hell.

 

[88mustangGT]

mine was locked up there to, i ended up geting a new rear end and when the old one was out i went at it again and i ended up stripping the damn plug. i think if its stuck its probly stuck. there was no way in hell i could of got mine out while it was still in the car i used the handeld to my jack on the end of my ratchet and thats what finaly turned square hole round

 

[hllon4whls]

I'm trying to change out the lubricant, but I can't get the bloody fill plug out. I don't want to proceed until I do. I'm pretty sure I have the correct location, but maybe I don't. What I'm trying to loosen is on the face of the differential facing the front of the car, about half-way up, on the drivers side. The only tool I can fit in the square hole is the drive for a 3/8" wrench. I've sprayed a couple of times with WD-40 and I'm about to go down and try again (waited about 20 min. now). Am I missing something here, I'm afraid to torque much harder for fear of stripping out the square hole

Take a small wire brush and brush what threads are exposed. Then squirt with WD-40. Repeat. This has always worked for me.

May want to do the first step with a degreaser to get all the gunk out of theway.
Then add the WD-40.

 

[HISSIN50]

use a nice well fitting extension and a breaker bar. you will be controlled and can see if you start to strip. of course, this is after the good advice on cleaning and PB'ing the thing.
BTW, good thinking. glad you were smart enough to loosen that (or try) before draining. many have not and have war stories to prove it.

 

[David Schwarz]

Success!

Man that was a PITA! But I finally got it out. The effort was well worth it too - no more chatter from my differential (see other thread on differential noise). Now the rear end is smooth as silk, and I'm one happy camper