I have just replaced all the bearings and seals in my 1968 Chevrolet C60 dump truck. I want to change the gear oil in the differential which is a GM3873551 that when Googled says it is a T170. Can anyone tell me how to drain the oil and how much oil does it hold? I am assuming it is 90 weight oil. I have read that you are suppose to fill the differential and then jack the truck up on each side to allow the oil to run over and fill the bearing wells and then top it off again. I don't see a drain plug on it anywhere. Thanks for your help.
I have the T170 also. I just changed the fluid in mine. It was about 1 gallon. I was using a hand pump on a smaller container to pump it in. The pick up tube didn’t reach the bottom of the quart container I was using but 2+ gallons seems like a lot.
It looks like the only way to really drain this thing is to take the bolts off the from. I was just told to be careful because of the 2 speed selector on it. Most of mine drained out when I changed the seals I left it as such. I have a small leak on the front side but I’m just dealing with it for now.
