I know nothing of transmissions so that's why I ask. So please anyone amount and type for a six speed allison
The initial fill (no fluid in trans, lines, converter, or pan) 12.7 quarts. If you just drain and fill and replace the filter, 7.4 quarts. If you do a flush you will need somewhere around 12.5 quarts. The Hoot Method is a way of flushing everything out. This write-up includes Trans go jr. install also, but look here for
Hoot Method instructions:
http://www.duramaxdiesels.com/forum/showthread.php?t=16176&highlight=hoot+method
Or, you can simply drain the fluid, change filter, and fill it with Transynd, drive it for a couple thousand miles (at least 500 miles) and then drain and refill. This will put the trans in the 95%+ synthetic fluid range, which is how I did it. I would recommend using Transynd fluid if the trans is stock. Merchant Automotive also offers a good synthetic trans fluid for this trans. I used the Transynd in mine. Though I don't have a modified transmission, I have read that if you have aftermarket trans clutches, i.e. ATS, Suncoast, etc. you should use a good DEX III fluid.
Since you say you don't know anything about trans stuff DO NOT OVER FILL the pan. At operating temp 175* check fluid with truck running. When you look at the dip stick you will see the area marked "HOT" with hash marks on each side of the word HOT. Fluid level should be in the lower hash marks (the end toward the tip) not in the HOT area or the hash marks above it. If you over fill the pan it will run hot. It's worth it to drain some fluid out, if you do over fill (take out the plug, let some fluid drain, re-insert the plug, check. Repeat as required). Good luck.
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