GM-GMC: draining converter on allison transmissions, allison transmissions, ford f250

Question
Is there any way to drain the converter of old fluid in preparation for installing new synthetic fluid. The vehicle is a 2001 Chev. 2500 4 W/D with allison 1000 series Trans. Previously I owned  Ford F250 with a 7.3 Diesel. the transmission was easily drained as well as the pan via accessable plugs.

Answer
I remember seeing a procedure for drilling and tapping a converter drain plug for some transmissions, but I would not recommend it for non-mechanics.  The risk of destroying the converter is high if the modification is improperly performed.

So, no, there is no way to drain the converter on your vehicle without removing it.  Even then, it is difficult to get all the old fluid of the converter.

You might check with an Allison dealer for the draining procedure, but I believe that the dealer will tell you that the converter would have to be removed.