buy both filters and take the one you dont use back, talk to the parts guy and let him know what you plan to do. I have never had an issue doing this before.

 

The deep pan refers to the 4L80 and not the 1000 Allison.

The Allison has an internal filter + an external spin-on.

The AC Delco parts lookup only shows 1 filter.

Vehicle: 2006 GMC Sierra 2500 HD 6.6L V8 Turbo DIESEL VIN:2,D New Vehicle
Group / Subgroup: Ignition/Filters / Filters & PCV

Auto Trans Filter Kit
Part Number: 24210956
Product Notes:
Auto Trans Filter Kit
All; Automatic Trans, 4L80-E, 4 Speed Trans, Transmission*
Per Vehicle: 1; Years: 2001-2006

Auto Trans Filter Kit
Part Number: TF329
Product Notes:
Auto Trans Filter Kit
All; Rear; 4 Spd; 4L80E/4L85E; 4WD; w/Deep Pan; w/o Pan Gasket; 4WD*; RWD*
Per Vehicle: 1; Years: 2001-2013

Auto Trans Filter
Part Number: TF920
Product Notes:
Auto Trans Filter
All; INTL; Automatic Trans, 1000, 6 Speed Trans, Transmission*
Per Vehicle: 1; Years: 2006-2006

Auto Trans Filter
Part Number: TF950
Product Notes:
Auto Trans Filter
All; EXT; Automatic Trans, 1000, 6 Speed Trans, Transmission*
Per Vehicle: 1; Years: 2006-2006

 

Rock auto is showing me two options for the allison 1000.

And i would love to buy both and return the one i do not use. But rock auto would not have it.

 

Buy locally and you have more options. Go to dealer with VIN and get the correct part.

Look it up at ►https://parts-catalog.acdelco.com/catalog/catalog_search.php