Hi guys. Im planning on changing my f&r diff fluid in the next few weeks and was wondering what size hex wrench it is? Any special compund I should put on the threads as well when re-installing? Truck is a '96 D1 with 127,xxx miles.

Thanks!

 

It's a 1/2" square, like on a 1/2" driver. I've never put anything on the threads. Get a nice fluid pump to put the new fluid in, like this:pump . Don't bother with the ones that screw onto a bottle, everything just falls over and spills under your truck and on you. Remove the fill plug first so you don't drain the diff and then discover you can't remove the fill plug for some reason.

 

Just torque it back up as per the shop manual, the plugs are easy to get going with a 1/2" breaker bar.

 

Nice. Thanks guys. Thought it was a hex socket for some reason. Do they sell sockets that are 1/2 square or do I just use a 1/2 socket wrench?

 

you can use a 1/2 in. socket wrench, if you plann to do your transfer case fluid too i would say get a breaker bar with a 1/2 in. head so you can do the t-case and you can use the same bar for your Diffs too

 

Perfect, thanks!

 

You will also need a 1/2 inch wobble extension for your transfer case, 4-6" long will suffice.

 

I could not get any kind of wobble extention into the limited space allowed for the Transfer case, I just used a 1/2 inch ratchet and removed the ratchet before it got trapped between the plug and the E-Brake Drum.

 

i had a serpentine belt tool i borrowed from a mechanic and it worked perfectly, but there are many ways to get that fill plug out. it is whatever works.

 

I have a wobble extension kit from Harbor Freight that had an extension in it that fit perfectly. Mine was in there good too.