Differential and Transfer Case Drain Bolts--Size and Type?

[eduJ]

I'm thinking of servicing my transfer case and differential fluids on my 98 Qx4 4WD. I did some research and looked underneath the vehicle. It seems like the bolt is a square bolt and not a hex key type bolt. What is this bolt called and what size socket should I purchase as it doesn't seem to be all that popular.

I recently purchased a socket set with 3/8 and 1/2 ractchets made by Stanley. Do I need a breaker bar or can I just heat up the bolt like others on this forum has suggested? Further, will I need a torque wrench to torque the bolt when I put it back in or can I just tighten it as much as I can? I can't see myself being physically able to torque a bolt to 80lbs in that position, which I believe is the spec?

Thanks in advance.

[asnorton44]

I cant remember the size but the transfer case drain bolt was easy; but the fill hole is at an awkward angle so I needed a pump to get the fluid in.

[Chuck Tribolet]

Socket needs to be 13mm square male. Some folks have made do with a 1/2" breaker bar, but some have also rounded out the hole that way.

Harbor Freight sells a set of metric square 3/8" drive sockets, which I did not buy because I want 1/2" drive (it can take a LOT of torque to undo those plugs) and tend to buy better quality stuff than Harbor Freight.

http://ultimatetoolco.com/13mm is a VERY nicely made (Snap-On quality) but pricey part which I have and have used. I later discovered I had a box wrench thing from my 240Z days but it's no longer made (maker is still in business).

ALWAYS remove the fill plug before removing the drain plug.

Chuck