How to sufficiently drain a 4L60e transmission.

tonyghkbve · March 25, 2014

I want to drain near 99% of the old ATF of my 2007 Silverado classic 1500 4.3 2wd truck. I had previously did a fluid (Valvoline DXRN VI) n filter (pro king filter) change on the truck at 30k miles, 4 years ago. The truck has about 53k miles on it now but this time I wanna do a complete service with DXRN VI and a WIX filter. So should i disconnect the AT cooler line from the top or bottom of radiator and let the truck drain all the fluid out before removing the pan the change the filter?

8.1HD/ALLISON · March 25, 2014

Only way to get all fluid out is to use a flush machine at a shop. Youll never get the fluid out of the torque converter.

Sent from my LGL86C using Tapatalk

CapitalTruck · March 27, 2014

You could do a complete fluid change by putting the lower cooler inlet hose in an empty bucket to collect fluid and the top cooler inlet hose in a container of fresh new fluid. The transmission should in theory suck the fresh fluid and pitch out the old fluid. However, having said all of that, it is normally not recommended that all the fluid be changed. A fluid and filter change (by dropping the pan) every 30k will do you fine. NO GM shop manual recommends doing a complete fluid flush. For what it's worth, I've got 183k on my original tranny (well, now my parents do) doing fluid/filter changes every 25k. And I have pulled some heavy trailers some long distances.

tonyghkbve · April 25, 2014

You could do a complete fluid change by putting the lower cooler inlet hose in an empty bucket to collect fluid and the top cooler inlet hose in a container of fresh new fluid. The transmission should in theory suck the fresh fluid and pitch out the old fluid. However, having said all of that, it is normally not recommended that all the fluid be changed. A fluid and filter change (by dropping the pan) every 30k will do you fine. NO GM shop manual recommends doing a complete fluid flush. For what it's worth, I've got 183k on my original tranny (well, now my parents do) doing fluid/filter changes every 25k. And I have pulled some heavy trailers some long distances.

And since you did that 25k ATF n filter change, has the transmission been very reliable at 183K with unnoticeable shifts?