Differential fluid change blues

[KathmanduCruiser]

Today, I started to change the oil on both diffs and the transfer case. I started with the transfer case, which went well. The old oil was looking really dark, but there was only a thin film of metal on the magnet in the drain plug. No problems on this one......

I started the rear differential next. The fill plug opened easily. The drain plug would not budge. I spent more than a half hour working on it. I sprayed blaster on it a few times and let it sit for a few minutes, but that did not help either. I was unable to open it. From me trying to unscrew the bolt, some of the sharp edges are looking less sharp. What should I do? Other than PB Blaster, I do not know what I can try on such stubborn bolts.

Now the front diff.... I tried opening the fill plug first. I tried to be careful with it, but it slipped right away. There is still some definition of an edge on the fill plug but only toward the end, and it will be very hard to get that out.

That is the trouble I am in. When I finally find a way to open the drain plug on the front diff (the one that slipped right away), I will replace with a new one. Same with the rear drain plug....

That is the problem though now - how to get it out?

Ideas will be appreciated.

BTW, I went with Mobil1 75w-90 synthetic.

 

[spressomon]

I don't think PB (or any other break free type of lube) will do you any good. Short of welding a throw away socket to the head of the nut and removing it...you'll need to use an Easy Out. FYI: I had dragged my rear end over a few rocks...bending the rear diff drain plug "protector" down onto the bolt head. A little work with a Dremmel or die grinder allowed me to get the socket on to remove the plug.

The front is tough if you are not using a newish sharp 10mm hex wrench; the best being the type that is attached to a socket so you can use a breaker bar.

 

[e9999]

aren't you glad you did the fill plug first....?

 

[Jim_Chow]

Assuming that you are replacing the crush washers with new ones, one toyota tech said if it's frozen, hit the bolt w/ a hammer first. This compacts the crush washer a little (hopefully) and unsticks the bolt.

 

[KathmanduCruiser]

aren't you glad you did the fill plug first....?

I understand the widsom behind removing the fill plug first. Thanks to the instructions in the FAQ.

 

[KathmanduCruiser]

Assuming that you are replacing the crush washers with new ones, one toyota tech said if it's frozen, hit the bolt w/ a hammer first. This compacts the crush washer a little (hopefully) and unsticks the bolt.

I did not even think that it might have been frozen. Tomorrow, it is supposed in the 40s, so I will give it a try again.And I did hit it a few times with the hammer. That did not help much. Maybe I was being too gentle though.

 

[KathmanduCruiser]

Short of welding a throw away socket to the head of the nut and removing it...you'll need to use an Easy Out. FYI: I had dragged my rear end over a few rocks...bending the rear diff drain plug "protector" down onto the bolt head. A little work with a Dremmel or die grinder allowed me to get the socket on to remove the plug.

Spresso, That is way too advanced for my novice-mechanic head. Now I know that the stupid looking thing surrounding the drain plug is called the protector and has a purpose though, hehe....

The grinder - that was to create enough space around the drain bolt to fit your socket, right?

I do not understand the part about "welding a throw away socket to the head of the nut.

The front is tough if you are not using a newish sharp 10mm hex wrench; the best being the type that is attached to a socket so you can use a breaker bar.

The 10mm hex wrench was just purchased today. The previous person who did the diff oil change might have over-tightened it.

 

[spressomon]

I did not even think that it might have been frozen. Tomorrow, it is supposed in the 40s, so I will give it a try again.And I did hit it a few times with the hammer. That did not help much. Maybe I was being too gentle though.

KC: I think he meant "frozen" as in "locked". There is a little give to those crush washers assuming the bolt has not been impacted on; good idea to try!

 

[KathmanduCruiser]

KC: I think he meant "frozen" as in "locked".

I really was taking the term literally.

 

[ppressle]

Could you get a pipe wrench on it? (It has been a while for me on that bolt)

 

[NMuzj100]

- PB Blaster overnight (it can take more than a few minutes for this to work into the threads)
- sharp taps with a hammer as suggested above
- then a little heat may be in order (Propane torch)
- a 24" breaker bar is also handy

 

[Jim_Chow]

I did not even think that it might have been frozen. Tomorrow, it is supposed in the 40s, so I will give it a try again.And I did hit it a few times with the hammer. That did not help much. Maybe I was being too gentle though.

By frozen, I mean seized due to overtightening, corrosion, etc. My front fill & drain bolts were really tight. Part of it was I couldn't get the car very high, so my 18" breaker bar was too long. Finally got it open w/ a standard 3/8" socket and bike seatpost as a cheater bar. Not enough space underneath to use my torque wrench, either. If I had a 2-post lift, it would be a breeze.