I did the Gear Box oil change with Royal Purple Synchromax yesterday night and I have to say that the shifts are smoother (especially when down shifting for some reason, and my forth gear that use to be rough is now pretty smooth).

I drained my old gear box oil (50800 miles on it) and it was not too bad (a little bit dark tho) and I tried to filter it to see if I would find some debris. I did find a few but nothing really big. I filled it back in with ~3.2 quarts before it starts overflowing. How much did you use Rocket254?

What about you? What were the main difference you've noticed after changing the oil?
Nice writings to both of you moosestang & Rocket254! Thanks

 

I must have really let mine drain out for a while as I put in 3 full bottles and then nearly half of another before it dripped out of the fill plug. At normal operating temperature, I'm afraid that a placebo effect may be in play. I'm not sure it actually helped that much but I'd like to think it did. Now cold weather is a different story. Last winter, my gearbox was a pain in the *** in the morning. Now it is a lot smoother.

Overall, I'm just glad I did the swap. It was/is peace of mind knowing that I have fresh fluid in there. Glad your swap out went well.

 

Just an observation. There's nothing wrong with Moose's method of going through the shifter opening, but if you get about a foot longer piece of tubing, it's very easy to route it up through the engine bay next to the battery. Just for those who might not want to risk getting any fluid on their interior.

 

I just used a pump. It worked for me.

 

I just wanted to add something to moosestang's thread:
When you take the Drain plug and the fill in plug out you can notice that they put some red Loctite on the thread. When I put these plugs back on I added some more red Loctite to make sure it was sealed and to prevent from any leak.

 

I never noticed that. Might have to check my transmission for leaks...

 

I noticed the Loctite but didn't have any available to put back on. I tightened the heck out of that plug. Hopefully, I'm ok...

 

I'm pretty sure y'all are ok as long as you tightened the plug good, I just wanted to point that out for the people who are planning on doing the gear box oil change in the future