Differential Allen Drain Bolt Buggered

[Gebo]

Trying to drain the front differential and the allen fitting has been buggered to the point that I can't get the drain plug out. What are some options?

I read where one guy dremmeled a square hole for a 3/8 ratchet extension to fit in. I could go to a muffler shop and have them weld a 3/8 extension to it.

 

[StevieC]

Do you have a picture to show us?

 

[Warstud]

Can you make the hole bigger to where the next size Allen Wrench will fit in ?

 

[Gebo]

Not tonight. I just got in the bed. I'll be back.

 

[StevieC]

Originally Posted by Gebo
Not tonight. I just got in the bed. I'll be back.


Ok... The reason I ask is because sometimes you can hammer in a Square Driver like a short extension into the messed up plug nice and tight which will allow you to take it out before resorting to welding a bolt onto it and doing it that way.

 

[clinebarger]

Find a appropriate sized TORX & hammer it into the Hex. If possible use a Impact & vary torque 'til it breaks free. OR it strips out the Hex completely & drive a larger Torx socket in.

First rule of differential service......Remove/Break loose the FILL plug first!

 

[mcwilly]

Originally Posted by clinebarger
First rule of differential service......Remove/Break loose the FILL plug first!


The second rule of differential service is you don't talk about differential service... hmm or was that fight club?

 

[KrisZ]

If the head of the plug stick out, I had good luck using a pipe wrench to loosen the plug. Vice grips are another option, but only on plugs that are not too tight.

 

[CharBaby]

I usually tap the plug with a chisel straight on to cut in a groove. Then with said chisel, tap the plug in the direction(CCW) to unscrew it.

 

[Trav]

If its like the one in the picture use a cold chisel on the right side of it at about 4 o'clock and hammer it CCW.
Make sure to keep the chisel flat as not to damage the case, you may get a few nicks and scratches but you want to keep it to a minimum. Use heavy sharp hits and open the fill plug first.

 

[dlundblad]

Depending on the room, you could just drill a hole in it and use a bolt extractor.

x2 on removing the fill plug first.

 

[Lubener]

Use a suction gun in the fill plug.. I think you will be opening a can of worms by trying to extract that plug.

 

[biggusblockus]

I have recently dealt with two of these stripped Allen head plugs, both Fill plugs. One on my daughters Lexus RX330 and the other on my Scag Zero Turn mower hydro. Both were solved by driving a Torx bit into the plug with a hammer.

Soaking the plug with Deep Creep or WD40 for a few hours before seemed to help.

When it breaks free and unscrews it is incredibly satisfying!

 

[Gebo]

Here are the pics. And the filler hole is loose

If this will help anyone else, I will offer some advice. If you are ever in a position of draining your diffs, don't be too lazy to get your vehicle up on ramps. Especially when your car is in your upstairs garage and your ramps are outside the basement door and a hurricane is bringing you a lot of rain. Especially after your confidence is high with the ease you had in draining and filling the rear diff and transfer case. It was so wonderful to use those gear fluid bags! Just insert and squeeze. No mess, no fuss.

It can be problematic when you use your left leg to push on the ratchet because you don't have enough ground clearance for a breaker bar and your foot keeps slipping off the ratchet and send the ratchet flying back to the rear differential area. Say 4 times?

 

[Gebo]

Originally Posted by biggusblockus
I have recently dealt with two of these stripped Allen head plugs, both Fill plugs. One on my daughters Lexus RX330 and the other on my Scag Zero Turn mower hydro. Both were solved by driving a Torx bit into the plug with a hammer.

Soaking the plug with Deep Creep or WD40 for a few hours before seemed to help.

When it breaks free and unscrews it is incredibly satisfying!


That day is coming....soon!

 

[Gebo]

Originally Posted by KrisZ
If the head of the plug stick out, I had good luck using a pipe wrench to loosen the plug. Vice grips are another option, but only on plugs that are not too tight.


I can barely get vice grips in there. You can see the results on the rim of the bolt.

 

[Gebo]

I think I will try the torx method first. Then the square extension.

Trav, you are my "go-to" man but that chisel thing....I'm not sure my testicles are big enough for that method as of 7:16 am this morning. Although there may come a time that I "Get mad at them eggs!"

Cool Hand Luke...

 

[BMWTurboDzl]

I guess this means the diff fluid is lifetime fill. too soon?

 

[CharBaby]

Originally Posted by Char Baby
I usually tap the plug with a chisel straight on to cut in a groove. Then with said chisel, tap the plug in the direction(CCW) to unscrew it.

Originally Posted by Trav
If its like the one in the picture use a cold chisel on the right side of it at about 4 o'clock and hammer it CCW.
Make sure to keep the chisel flat as not to damage the case, you may get a few nicks and scratches but you want to keep it to a minimum. Use heavy sharp hits and open the fill plug first.

Originally Posted by Gebo
I think I will try the torx method first. Then the square extension.

Trav, you are my "go-to" man but that chisel thing....I'm not sure my testicles are big enough for that method as of 7:16 am this morning. Although there may come a time that I "Get mad at them eggs!"

Cool Hand Luke...


Well, Trav & I have both said it and trust me, it works fine and without much hassle or damage.
I had to do this on my wife's Lexus. If you damage it, get another plug at the dealer. They're cheap enough!

 

[Omahaug]

I've ruined a rear differential drain plug like this before. This happens especially if you don't have the allen all the way in there (if for example there's rust or scale build up in the bore of the hex), then you're very quickly on the route to stripping it like this. It then no longer "bites" and just turns in place. In my case I used a 25 inch breaker bar and an 18 inch ratchet and it still wouldn't budge. I would put a huge amount of pressure on the bar and it would just flex, it eventually stripped. So now I had both the fill and drain stuck but the drain was stripped.

Want to know how I got it out after I stripped it like your picture shows?

I got an allen socket of a slightly smaller size (for example in SAE when the original size was metric). That let me get a little deeper in to get some more grip on the faces of the hex I hadn't ruined, this was just so that it would be less likely to "turn" itself out. Then the most important part was I hit the drain plug with my MAPP torch (yes that cheap 65.00 one from Home Depot).

After hitting it with a MAPP torch I was able to unscrew it with a regular 9 inch ratchet without having to push on it even a fraction of how much pressure I put on the breaker bar that made the breaker bar flex. That's how much of a difference that torch made. I find that in almost every case I need heat, the MAPP works just fine. Then I torched the fill plug that wouldn't come off before, guess what? Same result, came right off.

For the front differential I learned my lesson on the rear, tried a little bit of pressure, no give, stopped right there and hit both the fill and drain plugs with the MAPP torch, out they came without stripping anything that time at all.

So I don't even bother without the torch on those things any more, it's a waste of my time. The other advantage of the MAPP torch is it heats the drain plug enough to break whatever corrosion is holding it in place but not hot enough to destroy the magnet, since intense heat affects magneticity or even causes certain magnets (like the dark gray ones they usually use on OEM drain plugs and pans) to shatter.