Another rounded transfer case bolt thread (1 Viewer)

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If you're not familiar with my few previous posts, I got my 80 in December and I've been lurking on this great site and baselining my rig since. It's not my daily driver but definitely my Costco and Home Depot mobile on the weekends right now. Looking to get it ready for some tame wheeling within the year.

I'm working on flushing the transfer case right now. I don't know when the last time the PO checked or filled it. The fill plug/bolt is a bit rounded. I've sprayed the fill plug a few times with PB Blaster. After, I've tried using a 24mm socket to remove it, but can't seem to get enough coverage on the head to turn it. I used a 24mm wrench to try and turn it and it seems to want to round it even more.

I ordered a 24mm rounded bolt remover, the kind that bite into the head, but I'm wondering if that might destroy the bolt and/or damage the transfer case if the socket gets past the rounded bolt head.

Has anybody tried one of these bolt extractors on the transfer case fill plug? Any luck? As for the other solutions to this problem, what's the order of preference? Heat first, then hammer and chisel, then lastly trying to weld a nut on there?

Thanks for the help guys!

Ps. I ordered the allen wrench type bolts from Witsend to replace when this saga is complete.
 
What has worked for me is to take your socket and grind the end of it down. There is a chamfer in any socket, and in this size hex it is nearly the height of the head of the drain plug. Grind the socket back enough to eliminate the chamfer and the drain plugs come right out.
 
Are you using a 12 point socket or a 6 point? 6 point is the way to go. If you have trouble finding one, buy a impact 24mm socket. They are most always black, and 6 point. If the 6 point doesn't turn it, and it rounds it off, then move on from there.

If you can weld, I would go straight to that, especially since you have replacements on the way. You probably already know, the case is aluminum, so be quick about the welding Good Luck!
 
If you can weld, I would go straight to that,
Do what's suggested above, just tack weld a nut to the fill plug and remove it. Then replace both the fill and drain plugs with the easy to remove Allen wrench plugs from Cruiser outfitters.
1588891733091.png



Magnetic Drain/Fill Plug W/Gasket - $6.25/each
OEM Allen Head Toyota Drain Plug With Magnet
Fits 1958-1/1990 Manual Transmissions - Use Steel Gaskets
Fits 1958-2018 Transfer Case Drain & Fill Plug - Use Aluminum Gaskets
Fits 1958-1997 Front & Rear Differential Drain & Fill Plugs - Use Steel Gaskets
Fits 1998-2018 Rear Differential Drain & Fill Plugs - Use Steel Gaskets
Fits 1998-2007 Front Differential Fill Plug Only - Use Steel Gaskets
Fits 2008-2018 Front Differential Fill Plug Only - Use Aluminum Gaskets
 
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Do what's suggested above, just tack weld a nut to the fill plug and remove it. Then replace both the fill and drain plugs with the easy to remove Allen wrench plugs from Cruiser outfitters.
View attachment 2298923


Magnetic Drain/Fill Plug W/Gasket - $6.25/each
OEM Allen Head Toyota Drain Plug With Magnet
Fits 1958-1/1990 Manual Transmissions - Use Steel Gaskets
Fits 1958-2018 Transfer Case Drain & Fill Plug - Use Aluminum Gaskets
Fits 1958-1997 Front & Rear Differential Drain & Fill Plugs - Use Steel Gaskets
Fits 1998-2018 Rear Differential Drain & Fill Plugs - Use Steel Gaskets
Fits 1998-2007 Front Differential Fill Plug Only - Use Steel Gaskets
Fits 2008-2018 Front Differential Fill Plug Only - Use Aluminum Gaskets

When these drag over enough rocks they work their way loose and can come out when wheeling. It's happened to me and a handful of other people I know.
 
When these drag over enough rocks they work their way loose and can come out when wheeling. It's happened to me and a handful of other people I know.
I'm sure that strange things like having your drain plug fall out after you've dragged it over rocks is possible. But i really don't see how a flush Allen style plug would come out any quicker then a hex head would if they were both dragged across rocks.
 
All I'm saying is that it happens.
They aren't "flush" ether.
In my old rock crawler the lip around the plug was ground down enough from rocks that the plug was able to work loose. I've also seen it happen on diffs that had all the lip around the plug.
I ran them in another crawler and never had an issue with them.
 
They aren't "flush" ether.

You're right, the replacement Allen head plug is not flush when installed, i just measured a brand new Allen plug, with a new, unused crush gasket, and it had an over all height of .220 thousands of an inch. Once install, and the new crush gasket flatten, the overall height of the Allen plug will be even a little shorter.

Then i measured the used factory fill plug installed on my truck, it measured with a used crush gasket at .275 thousands of and inch. That's almost a 1/16 of an inch difference in height, a difference where the old factory plug sticks up higher then the replacement Allen plug will.
 
Are you using a 12 point socket or a 6 point? 6 point is the way to go. If you have trouble finding one, buy a impact 24mm socket. They are most always black, and 6 point. If the 6 point doesn't turn it, and it rounds it off, then move on from there.

If you can weld, I would go straight to that, especially since you have replacements on the way. You probably already know, the case is aluminum, so be quick about the welding Good Luck!

The socket I’m using is a black impact socket, 6 point, and feels like it’s getting past the bolt. So should I try to grind down this socket?

Never welded before so that might be out of the question for me any time soon.
 
Do what's suggested above, just tack weld a nut to the fill plug and remove it. Then replace both the fill and drain plugs with the easy to remove Allen wrench plugs from Cruiser outfitters.
View attachment 2298923


Magnetic Drain/Fill Plug W/Gasket - $6.25/each
OEM Allen Head Toyota Drain Plug With Magnet
Fits 1958-1/1990 Manual Transmissions - Use Steel Gaskets
Fits 1958-2018 Transfer Case Drain & Fill Plug - Use Aluminum Gaskets
Fits 1958-1997 Front & Rear Differential Drain & Fill Plugs - Use Steel Gaskets
Fits 1998-2018 Rear Differential Drain & Fill Plugs - Use Steel Gaskets
Fits 1998-2007 Front Differential Fill Plug Only - Use Steel Gaskets
Fits 2008-2018 Front Differential Fill Plug Only - Use Aluminum Gaskets
Just replaced mine with all socket head plugs as shown.
 
You're right, the replacement Allen head plug is not flush when installed, i just measured a brand new Allen plug, with a new, unused crush gasket, and it had an over all height of .220 thousands of an inch. Once install, and the new crush gasket flatten, the overall height of the Allen plug will be even a little shorter.

Then i measured the used factory fill plug installed on my truck, it measured with a used crush gasket at .275 thousands of and inch. That's almost a 1/16 of an inch difference in height, a difference where the old factory plug sticks up higher then the replacement Allen plug will.

I'm glad you felt the need to measure everything to try to prove me wrong. On paper it looks great.
In some real life instances (not all obviously) what has happened to me and many others happens. Maybe not to you in an all stock 80, but it happens.
I'm not telling the OP to not buy them, but if his wheeling style is like mine, it's something to look out for.

Have a great day
 
I have ground down the chamfer of my 24mm along with a 17 and 14 for just such occasions.
It works exceedingly well for transfer case drain/fill as well as diff fill plugs.
I also never use 12 point anything, but I live in the northeast.
IMO, there is no need for the allen head drain/fill replacements for the transfer case or the diff fill plugs.
And the allen head diff drain plugs will absolutely walk out just as easily as the standard ones if you start dragging them over rocks. Been through that way too many times already.

20200508_100525.jpg
 
Also, to substitute for the 24mm, use a 15/16 hex socket and grind that down on the face. The 15/16" is slightly tighter than a 24mm socket.
 
I well jump in with my 2 cents on the Allen head fill and drain plugs.
My 80 is a dedicated Trail Reg Rock Crawler and get wheeled hard. For me when I was running the stock plugs the protection rings that are around the plugs got so ground down and into the plugs that you couldn't get a socket on the plug. Now that I have the Allen head Style I have always been able to get a Allen wrench in there.
I have never had one come lose or out on me.
I also added 3/8" plate to the bottom of both Diffs with built up weld around both drain plugs. This has held up well as the welds are much harder the the metal.
In a nut shell I like the Allen's better for hard core wheeling ;)
 
Also, to substitute for the 24mm, use a 15/16 hex socket and grind that down on the face. The 15/16" is slightly tighter than a 24mm socket.

Yeah, thinking now I should have tried that from the get go. This is a great tip.
 
Ok guys great success, not without a lot of cussing and deep breaths of course.

Winning technique was: 15/16 6-point deep impact socket, ground down with a hand grinder. Then tried to maintain as much positive pressure on whatever surface angle (it was definitely not on fully straight on the bolt head) was grabbing the plug head as I was torquing to break it loose. Was about to give up till it finally opened up for me.

Transfer case oil was dark black. Filled it with fresh Valvoline 75-90, buttoned it up with the new Allen type hardware and took it out for a well-deserved Saturday night spin.

Thanks everybody!

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Did you ever try grabbing it with some sort of pliers, vise grips, etc? It really looks like a pipe wrench would have done the trick pretty good as well. :meh:
 

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