Transfer case fill plug seized & head spun out!

[Ironring1]

Hi, all. I was about to do a transfer case fluid change on my 2002 Envoy. This is a used truck, and I've only had it a few months. I hadn't wanted to drive it much until I had done a transfer case fluid change.

Well, I jacked up the truck, undid the drain plug, and only after I had drained the fluid did I realize that the fill plug was completely seized into its hole! I thought that I had gotten it loose, but it turned out that it was my 10mm hex key socket spinning inside the socket on the plug!!! Now, I managed to get at least a litre of fluid into the TC by running a small air hose up through the drain hole as high in the TC as I could, then wrapped my oil transfer pump tube in a rag to seal the hole, then pumped in fluid. I measured what spilled out when I quickly removed the rag and put the drain plug back on, so I am confident that there is fluid in there.

My question is, now what do I do? I could take it to a shop if I have to, but are there any suggestions on how to get this thing out? I can't drill out the bolt, since there isn't enough room to get a drill behind it (and even if I could, I would be worried about getting chips inside the TC.) I had sprayed some liquid wrench on the plug, but it didn't make much of a difference. Will the shop even be able to get it out?

Thanks,
-Chris

 

[triz]

Probably one of the reasons people say to make sure you can get your fill plug off first. Try a bigger hex key first. Only other thing I could think is maybe try a pair of offset needle nose pliers and try to rotate it out. Hammer and screw driver to get it loose?

 

[Ironring1]

As soon as I realized it was stuck, I realized that I had made a big mistake taking the drain out first. I tried the fill for the front diff before attempting the drain for it, and it's pretty stuck, too. Rather than make a bad situation worse, I will take it to the shop next week and let them get both fill plugs out for me... If I had some decent welding equipment, I would weld some keystock to it, and from what I understand, the heat would loosen the plug, too. I am pretty sure that this is what the shop will do.

 

[IllogicTC]

Isn't that how life goes? You go outta your way to keep something nice and this happens, it's like feeding the birds just to have them poop on you.

Using a bit of heat to help ease the plug out, too.

If you manage to get it out, I'm sure you'll want a replacement one so you won't have to worry about the screwed-up hole next time. I believe the part number is 89059626. Hits on several GM parts sites like GMPartsDirect and GMPartsEast for like $5-7, but there is probably a S&H fee that would run that up to about the $12-15 range I'd figure. You may get lucky and find one on eBay or Amazon, too. Torque spec putting it back on is 20 lb ft.

 

[Texan]

Those type of plugs are pretty common on a lot of vehicles. It makes wonder if somebody
does not make a special tool (easy-out type) for this purpose. Add a little heat and it
might work. Just a thought.

 

[Mark20]

Would you heat the plug, area around the plug or both?

 

[Playsinsnow]

Would you heat the plug, area around the plug or both?

The plug very slowly. It will warm up around it and break the seam. Or move the heat if hot around the outer end, thread, to loosen has worked for me.

 

[Texan]

Just curious. Is the transfer case CI or Alum. Limit the amount of heat used.
I have a feeling the plug may be steel, but don't know.

 

[The_Roadie]

All that New Venture Gear stuff is aluminum.

 

[blazinlow89]

Its definitely aluminum. I think GM learned some lessons with galvanic corrosion.

A couple of solutions, if you have some of the torx bits, you may be able to get on to fit snug enough to get a few good turns on the plug. Or you could try the larger screwdriver as always.

 

[jsheahawk]

If you've really, really rounded out the hole, you can try carefully cutting a slot into it with a dremel. A screwdriver socket with some heat will probably get it out.

Silver lining: you will never, ever take the drain plug out first again.

Jared

 

[{tpc}]

This seems like an appropriate thread to ask this question in. For the fill plug, what size or what tool is the exact proper one to use? Just in case I ever get daring enough to attempt this, lol. I am assuming it is a 10 mm socket-ed hex key, but just wanted to make sure there wasn't a "special" tool for it. (Kinda like the special slotted 18mm deepwell socket I had to make for the coolant sensor, lol)

 

[Dad-O-Matic]

I am assuming it is a 10 mm socket-ed hex key

Correct. Some people use a 3/8" hex, but that is slightly smaller than 10 mm and you run the risk of rounding out the hole.

 

[jpimp]

heat it up...just be careful these aluminum transfer cases melt easily...don't ask me how I know, lol

Edit: for Bill05EnvoySLT below, to not clog up OP thread.
I didn't move the heat around enough and almost melted right through the front of the case LOL. Oops. It was close but I got the fill plug out and didn't completely ruin the case.

 

[Bill05EnvoySLT]

Correct. Some people use a 3/8" hex, but that is slightly smaller than 10 mm and you run the risk of rounding out the hole.

OK so a 10MM Torx or 10MM Hex ? I Think I have both but want to get this done too. (ill saturate the plug well before trying it. I would think on a 2005 it should not be that corroded

heat it up...just be careful these aluminum transfer cases melt easily...don't ask me how I know, lol

Im curious now??? how do you know

 

[davenay67]

Everyone has mentioned heat.

Also, use copious amounts of PB Blaster spray over a period of a few days. Additionally, you can shock the plug by lighly rapping on it with a hammer. Be careful around any aluminum parts.

A combination of PB Blaster, heat and a hammer will make even the most stubborn bolts yield eventually.

 

[MAY03LT]

On the other site, some folks would try using a little "L" shaped 10mm allen to get the check/fill plugs out. This is what I use, and in some cases I have to use a 1/2" drive ratchet to get a little more umph on them.

 

[C-ya]

OK so a 10MM Hex

Yes. I used the L-shaped hex, put I used pliers for leverage.

 

[Robbabob]

Those type of plugs are pretty common on a lot of vehicles. It makes wonder if somebody
does not make a special tool (easy-out type) for this purpose.

I think I read someone uses a 3/8" square drive.

That would be a hair under sized, but possibly hold enough surface area than a spinning 10 mm.

Edit:

OK so a 10MM Torx

I would stay away from torx for this... there's less surface the wrench will be touching than using a hex or even a 3/8 drive. Just my opinion. ~Opinions are like noses~ (put nicely)

Edit 2:

Yes. I used the L-shaped hex, put I used pliers for leverage.

Think that is what I used 14 months ago, before reading so much more. FILL plug definitely came off before drain plug (yup, learned that here on GMTN)!

 

[The_Roadie]

3/8" square is only for rear differentials. Others we're discussing are hex.

 

[Bill05EnvoySLT]

I think I read someone uses a 3/8" square drive.

That would be a hair under sized, but possibly hold enough surface area than a spinning 10 mm.

Edit:



I would stay away from torx for this... there's less surface the wrench will be touching than using a hex or even a 3/8 drive. Just my opinion. ~Opinions are like noses~ (put nicely)

Ok So my original TXT was asking about TORX or HEX as I was unaware which one it was, someone else replied quoting me with HEX and your quoting me with Torx
Just to clear this confusion up... ITS HEX 10MM I got this now
Thanks
Bill

 

[blazinlow89]

The torx bit input was from me. In the past when I have a hex bit that will not grab, I have been able to tap a torx bit in of a slightly larger size. Then turn slow. A torx bit in a hex hole does have less surface area to grab, however tapping in the next larger size can give something to get a few solid turns to help get the plug out.

A note of caution, you will need a new plug to replace the old one. You may also damage the torx bit beyond further use.

10mm is the correct size for the plugs.

 

[Ironring1]

The torx bit input was from me. In the past when I have a hex bit that will not grab, I have been able to tap a torx bit in of a slightly larger size. Then turn slow. A torx bit in a hex hole does have less surface area to grab, however tapping in the next larger size can give something to get a few solid turns to help get the plug out.

A note of caution, you will need a new plug to replace the old one. You may also damage the torx bit beyond further use.

10mm is the correct size for the plugs.

I agree about using a slightly oversized torx; I tried this but it still wouldn't budge... As for 10mm vs 3/8", the auto industry has been metric for quite some time. Of course, there usually is a close sae/imperial equivalent to most metric sizes, but the metric ones will be exact.

 

[The_Roadie]

As for 10mm vs 3/8", the auto industry has been metric for quite some time.

And strangely enough, even metric vehicles like this one use a 3/8" square recess, that matches socket set extensions, for rear differential drain and fill plugs. An odd holdout I never understood. I see 8 and 10mm square recesses for Japanese vehicles, and I haven't owned a European one recently.

 

[RayVoy]

The very best penetrating oil is a 50/50 mix of Auto Trans Fluid (ATF) and acetone.

As I said, mix it 50/50 and use a small spray bottle, or soft sided oil bottle. Let it sit for a few hours, or overnight and the plug will come out very easy.

 

[Texan]

The very best penetrating oil is a 50/50 mix of Auto Trans Fluid (ATF) and acetone.

As I said, mix it 50/50 and use a small spray bottle, or soft sided oil bottle. Let it sit for a few hours, or overnight and the plug will come out very easy.

Here I go thinking again. Is fingernail polish remover and acetone more or less alike?

 

[RayVoy]

Here I go thinking again. Is fingernail polish remover and acetone more or less alike?

Haha, yep, same thing...............stop thinking

 

[The_Roadie]

........stop thinking

More importantly....stop sniffing it!

 

[IllogicTC]

And strangely enough, even metric vehicles like this one use a 3/8" square recess, that matches socket set extensions, for rear differential drain and fill plugs. An odd holdout I never understood. I see 8 and 10mm square recesses for Japanese vehicles, and I haven't owned a European one recently.

Our speedo is still in MPH, too, and that's not even bringing up the PSI-measured oil pressure and fahrenheit readout on temperature.

The tensioner also uses a 3/8 recess to loosen it up, while my roommate's 97 Dodge you hook a metric socket up.

 

[Sparky]

And strangely enough, even metric vehicles like this one use a 3/8" square recess, that matches socket set extensions, for rear differential drain and fill plugs. An odd holdout I never understood. I see 8 and 10mm square recesses for Japanese vehicles, and I haven't owned a European one recently.

And those U joint bolts on the rear diff are SAE also. To add to the confusion. 7/16" or something like that. Any metric size I tried was sloppy.

 

[ddgm]

For what it's worth, only the USA, Myanmar(Burma) and Liberia still use the "English" units of measurement.
Canada, IIRC, changed to metric in 1974. So, 40 years ago, our system changed and I still do conversions in my head.
For 4 years now, I have lived 6 months in Ontario and 6 months in Florida and cope with the differences well as "English" was the system
I learned through my school years. Metric is a better and easier system to use and learn as everything is multiples of 10, the medical community
adopted it ages ago. However, it would be extremely costly to convert. Things like road signs, maps, gas pumps, etc. Luckily, on my Cadillac, I can just push a button and it switches between the two, same for my Garmin. My Saab 9-7x doesn't, but I leave it in Florida, so no biggie. My 2 cents. By the way, we even did away with our penny, so it will have to be my nickles worth.

Doug

 

[Mooseman]

Back on topic. If all else fails, take it to a shop and have them weld a bolt onto the plug. Both the bolt head and heat will help get it off.

 

[jsheahawk]

So what ended up happening, OP?

Jared

 

[Ironring1]

Hey, all. I thought that I would post an update. My local shop didn't charge me extra to remove the stuck plug, just the regular fluid change cost (less the actual fluid, as I supplied it to them), so it was a relatively painless mistake. The cost of a new plug was $15 (Cdn) after taxes. At that cost, I got a spare and put it in the glove box.

The guys at the shop I go to are great (Long Lake Automotive in Nanaimo), and run a great little operation. I have no financial association with them, but I like to give the local "little guys" a plug when I can to help them out.

 

[jsheahawk]

Hey, all. I thought that I would post an update. My local shop didn't charge me extra to remove the stuck plug, just the regular fluid change cost (less the actual fluid, as I supplied it to them), so it was a relatively painless mistake. The cost of a new plug was $15 (Cdn) after taxes. At that cost, I got a spare and put it in the glove box.

The guys at the shop I go to are great (Long Lake Automotive in Nanaimo), and run a great little operation. I have no financial association with them, but I like to give the local "little guys" a plug when I can to help them out.

I'm glad you got it fixed. How did they get it out?

Jared