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front diff drain plug on too tight

10K views 20 replies 8 participants last post by  2010toyotafj46 
#1 ·
Re: Front Diff Plug :surprise
hi, went to help a buddy do diff fluid change on his 2007. the rear and transfer case went smoothly, but for the front were able to open the fill plug no issues but went to open the drain plug and oh boy!! it was on so tight, it just would not budge with even a breaker bar. even tried air ratchet which still would not get it to budge. It did strip the plug so now in a jam and dunno how to proceed?/
What are some options in this situation??
Thanks for your help.
 
#2 ·
That sucks! I had to once carefully weld a socket onto a drain plug In order to remove it. Not sure if you have access to other extracting tools...I found a set of cheap Harbor Freight wrenches that are made to grab the bolt head after they have been rounded off and it actually worked. Good luck!
 
#4 · (Edited)
This is the unfortunate consequence of just continuing to blindly apply ever increasing levels of force. When it became obvious that the plug was not going to turn with a reasonable level of force, it was time to stop, think and utilize some alternate process to break the threads free. NEVER USE A RATTLE GUN TO TRY TO REMOVE ANY DRAIN PLUG WITH A FEMALE HEX DRIVING RECESS!!

1. First, are you absolutely sure that you were turning the plug in the correct direction to unscrew it? Incredible as it sounds, more than once I've seen people get confused trying to loosen a fastener that's "inverted", and were turning it clockwise to try to remove it. MAKE SURE YOU'RE TURNING THE PLUG IN THE CORRECT DIRECTION!!

2. Depending on how badly you've "reamed" out the 10mm drive recess, usually a male T55 Torx driver bit (11.2mm across the "star") can be hammered into the plug and then used to unscrew it. The process of hammering the driver into the plug will usually help break the threads free, and it will unscrew relatively easily. This is usually 99% effective.

3. If the plug still doesn't unscrew using a reasonable amount of torque (no 2-foot breaker bar or impact wrench, please), use a propane torch to heat the diff housing immediately surrounding the plug. You don't have to get it excessively hot, just hot enough to expand the threads in the housing by a few thousandths of an inch. Hot enough to sizzle spit on a fingertip is more than hot enough.

4. Are you absolutely sure you were using a 10mm hex wrench and not a 3/8?"? There are probably more 10mm female hex drain "stripped out" by using 3/8" hex drivers than by any other cause. Make sure that you've got a high-quality 10mm hex driver, not some cheap, soft or undersize tool. Its too late for this plug, but its something to remember the next time you attempt to remove a plug with a female hex driving recess.
 
#12 ·
Thanks, Your advice worked as it took some doing and improvising, Here is what I ended up doing for anyone else with similar issue. First off I like to say that being a Farmer I have done my fair share of fluid changes on all kinds of Farm equip and vehicles and never have I come across a diff drain plug so tight. It seems whoever did the fluid change before me had to have used air impact gun with high torque to tighten the drain plug.
Now on to what worked. As suggested by Fjtest, I hammered in a impact torx T55 into the striped hexagon 10 mm hole, it fit pretty tight and i was optimistic at this point it would work for sure. using a breaker bar when I applied pressure, I had to apply a fair bit as it would not budge and ended up striping it and making the hole bigger. Next I heated up the diff housing around the plug used T60 Impact bit and hammered that in and again no luck it striped even further as little chunks metal fell out. since I was past the point of no return, I decided to T-70 torx impact bit and hammered that in as the bit was lot bigger than T-60 it took a far bit of pounding to get it to wedge into the drain plug. Once it was wedged in good I decided to used an air impact gun to loosen it as manual leverage was not working for me.
:rocker::blueblob::clap: It working as It finally freed the plug.
So a big thank you to Fjtest and all others for their suggestions and ideas.
 
#5 ·
Thanks for very good advice. I was using a 10mm good quality hex wrench key and going counter clockwise. As I said earlier had no issues opening the rest of the plugs on rear diff, transfer case etc. when got to the front diff first tried just using the hex key handle when that did not work, tried a small piece of pipe about 1 foot long to exert more force on hex key. after used a 10mm hex socket with the breaker bar, no luck with that so finally tried air ratchet making sure always it was turning counter clockwise. This is my buddies truck and this was the first time he is doing all the diff fluids. its got 50,000 miles and he bought it used with 30,000 miles. seems to me whoever did the last diff fluid changes over tightened everything. also there seems to be lot of rust all around the bottom, like originally maybe the truck came from rust area.
I will try your suggestions of hammering T55 torx/ heating and see what happens.
Thanks for excellent advice. much appreciated.
 
#6 ·
I had a similar problem with my front diff. I had ordered a new plug and hex driver because i thought i was going to have to weld the driver onto the stuck plug. I ended up getting it off by smacking the breaker bar with a hammer . In your situation a welder may be required if the torx bit doesn't work.
 
#8 · (Edited)
these came way too tight from the factory. I had the same problem. First, go to a dealer and get a new plug and copper gasket. Spray it with liquid wrench or such overnight. Heat it up with a propane torch. Try hammering the next size socket in there. Between the torch, the liquid wrench, and the hammering, I was actually able to get the 10mm one to catch just enough to break it loose with not much force. Make sure you use a torque wrench to tighten new one on, I believe it is only 29lb/ft. Oh, make sure you put anti-seize on it too.
 
#9 ·
these came way too tight from the factory. I had the same problem. First, go to a dealer and get a new plug and copper gasket. Spray it with liquid wrench or such overnight. Heat it up with a propane torch. Try hammering the next size socket in there. Between the torch, the liquid wrench, and the hammering, I was actually able to get the 10mm one to catch just enough to break it loose with not much force. Make sure you use a torque wrench to tighten new one on, I believe it is only 29lb/ft.
would you know thw part number ?? thanks
 
#15 ·
Spraying Liquid Wrench on the plug won't accomplish anything because the threads are inboard of the copper gasket.
All I can say is I used Aerokroil on mine and let it sit overnight. The next morning I was able to get it loose. I can't prove that Aerokroil was the trick but it didn't hurt. Also, I have never had any luck with a propane torch when freeing a stuck bolt or nut. For me it has always taken a full on oxy torch or the heat from welding on a nut. Most of the time a good smack does wonders though.
 
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