Need help in adding sound to Athearn SD40-2 (Dummy Unit)

[Texas Zepher]

Cut some pieces of hollow cylindrical styrene to the right length and press the axles into that.  It comes in plenty of sizes so one will surely fit the 1/2 axles.

[rrinker]

 Your LHS can order the parts directly from Athearn, they're only a couple of bucks for a complete set of geared axles. Also suitable to replace cracked P2K axle gears.

                                    --Randy

 

[jamnest]

I have purchased several Athearn SD40-2 units on Ebay which I want to add sound only decoders.  The Athearn dummy units have the metal electical pick-up in the wheel set, but have solid plastic wheels.  I have purchased replacement 40" wheels from NWSL, however they are 1/2 wheel sets and need the Athearn wheel set gears, which I don't have, to replace the dummy one piece plastic wheels.

I intend to place a sound only unit in each consist as an inexpensive way to add sound to my locomotive fleet.

Can anyone suggest an inexpensive source for the Athearn wheel gears or suggest a subistitute?