Why is the drain in the Allison pan recessed? [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: Why is the drain in the Allison pan recessed?


Roegs
07-21-2004, 08:26 PM
I have changed the filter, but not the fluid yet. I was looking at it last night, and the drain seems to be recessed into the pan a good 1/2 inch. When I remove the drain plug, doesn't that leave the last 1/2 inch of fluid in the pan?


On all my previous trucks before this, I used a hand pump down the filler tube to drain and refill fluid a couple of times a year as kind of a poor mans way to keep fresh fluid in it (still dropped the pan and changed filter at recommended intervals). I pumped the fluid into a marked container, and refilled. It was really an easy process. Can I do the same with the Allison, or am I better to just pull the drain plug? Also, the recommended refill when pulling the drain plug is 7.4 quarts, does that include the filter? Thanks!

Amric
07-21-2004, 09:09 PM
7.4 quarts does include the filter.


It is recessed for protection from rocks since there is no shield under the Allison.