Trouble removing the rear diff fill plug

[Mbrooks420]

My rear diff has a pinion seal leak, which I can't take care of right now, (temporarily without a garage) so I planned on checking and filling as necessary until I came get this done. Problem is, the fill plug is TIGHT. I'm afraid of stripping it out. I only had a 6 inch ratchet on it, but it was SNUG. Do I just need to use a larger ratchet? I've had it off before, and I usually don't tighten things to the max.

Kinda freaking out. I really don't want to have to rush ship a $150 cover with a fill plug.

Help!

 

[96eb96]

Try some heat around the plug. Mine took quite a bit of force to get off, I think I ended up using an impact. I would try a 1' breaker bar. If you had it off before, it will likely come loose.
You can also spray it down with ATF/Acetone, penetrating fluid, etc. overnight.

YMMV if it rounds out or not, depends on how hard the tool is.

 

[swshawaii]

^ Ditto above. Penetrant, heat, and a breaker bar or short cheater pipe for leverage. 3/8" square drive plug rounds off easily and strips because it's shallow depth and soft metal. Clean threads, and use a couple wraps of teflon tape when replacing.

 

[koda2000]

I doubt you'll strip it out, but they can get rusted in there pretty tight. I'd use my impact on it to rattle it out, or stick a short socket extension in to and smack it a few times with a hammer to break the rust free. Don't be afraid to add a length of pipe to you 6" ratchet for more leverage.

Honestly, I've never found penetrants to be of much help in breaking a rusted bolt free. Once you can get something to move a bit they can be helpful, but you can soak the crap out of something for days and have no effect. Heat and/or impact works much better.

BTW - Those fill plugs (and drain plugs) are a tapered/NPT thread and don't need to be super tight to seal. Over tightening one in aluminum, like on a t-case, could crack the case. Not much chance of that on an cast iron diff case though.

If worse comes to worse and you can't get the plug out, you can always add a fill plug to the diff cover. Just make sure the location of the plug doesn't interfere with any moving parts.

 

[Mbrooks420]

I've had it out since winter, so it shouldn't be that rusted. I can't believe I over-tightened it. I'm going to try heating it up a little tonight and giving it a few good rapse cover with a hammer. I've got an 18 inch breaker, I just didn't have my 1/2 to 3/8 adapter. Since I'd have to yank the cover to add a full plug, I'd probably drop the $100 on a cast cover with fill and drain.

 

[96eb96]

I've had it out since winter, so it shouldn't be that rusted. I can't believe I over-tightened it. I'm going to try heating it up a little tonight and giving it a few good rapse cover with a hammer. I've got an 18 inch breaker, I just didn't have my 1/2 to 3/8 adapter. Since I'd have to yank the cover to add a full plug, I'd probably drop the $100 on a cast cover with fill and drain.

DR3Z4033B, $70 bucks shipped on ebay. Not bad

 

[Mbrooks420]

https://www.amazon.com/gp/aw/d/B00F...tial+cover&dpPl=1&dpID=41UfVtwVhRL&ref=plSrch

Was looking at that one, but I'll check the other out.

 

[boominXplorer]

A factory 02+ irs rear half can be cut up and made into a cover with a girdle with drain and fill plugs. Probably find one of these pretty cheap.

 

[Mbrooks420]

Anyone know the size? 1/2NPT?

 

[Mbrooks420]

Well, I got it out. I cleaned it really good, and found a 3/8 drive with a sharper square. Hammered it a few times, and twisted it out with my breaker. It's pretty chewed up.

Ended up finding one, after 4 calls. Auro store workers are nearly useless these days. Stopped at an Advance on the way to Lowes on the offhand chance I could find one myself, and was asked if I needed help by a girl in her early 20s. I asked for a 1/2 NPT, and she walked right behind the counter and grabbed it. Shocking. This one has a tight fitting Allen head that I feel a little better about. $50 later and I'm rolling again.

 

[swshawaii]

Great to hear! For future reference, DMP Fasteners has stainless magnetic NPT plugs for a reasonable price.
http://dmpfasteners.com/shop/1-2-npt-pipe-plug-stainless-with-magnectic-tip-3764

Used them to replace the steel drain and fill plugs supplied with the Moser 8.8 cover.
http://dmpfasteners.com/shop/an-fittings-and-hose-1647/xrp-fitting-349/pipe-plugs-2528/