There is one basic Piper part number covering the two manufacturers; they are interchangeable.

A suggestion for easy determination of which transmission manufacturer you have installed; click on each photo below, print them and take to your airplane for comparison.

The photos below show you how to identify the differences between the manufacturers; there are a few ways besides the above illustrations. The Dukes uses 6 countersunk screws holding the end plate to the housing; the Dura uses 5 non-countersunk 10-32 screws. The Dura must have the bearing retainer; the Dukes design does not require that band-aid. The Dura has 4 holes, 2 used for the motor mounting; the Dukes uses either a slotted design [above] or one with 2 holes, one hole per leg [below]. The Dukes photo above shows the slotted design. So there you have it again, more information than you really wanted to know.

Contact me with any questions about availability or servicing these transmissions.

Dura Transmission

Dura Transmission – most common type

Dukes Transmission

Dukes Transmission – more durable type


Dukes with 1 hole per leg – note hole offset aft of centerline


Illustrating “clock” position of mounting plate

Service Letter #447

Notes and Repair Information

The Dukes transmission [without motor, brake, and release arm] can be overhauled at Dukes, Inc for approximately $3,200 which is the latest quote I have from them; I no longer keep a Dukes overhaul on the shelf for exchange. However I do have exchange Dukes units available [not Dukes, Inc OH]. See the parts for sale page. If you choose the Dukes Inc repair, your transmission will be returned overhauled but they [Dukes] do not consider cosmetic improvement of the tube and release lever a part of their service, because they supplied the transmission to Piper without that component. I have the tube and release lever done separately; you may likewise.

Dukes, Inc says that they have never released a repair or maintenance manual for these transmissions. They continue to say, therefore how can anyone else claim a repair on an 8130 referencing what manual? So if this is accurate information, then the only approved repair facility for the Dukes transmissions is Dukes, Inc. I could be wrong on this opinion.

And if you aren’t bored enough just yet, there is a note in the Single Comanche Parts Catalog concerning the Dukes transmissions. It seems there was a bad run of actuator screw from serial number 919 through 1068 [see SL-650 above]. If you have one in that serial range you must replace it immediately.

If your Dura transmission has a loose bearing, you are probably out of luck. I usually have a Dura on the shelf for exchange. I am not aware of any facility holding an approved process to repair this problem except the facility in Michigan who charges about $3,300; some may be on the horizon. Again if your Dura has a bearing retention problem you had best find a Dukes to replace it before the supply dries up. The Dukes transmissions were demanding $2,250 in used condition, no motor. From there you’ll have to do an inspection and if the gears are bad, add another $3,200 to get it repaired at Dukes.

More recently these transmissions [without release arm and motor] are fetching nearer to $3,000 on the tail of the statement that Dukes quoted me $8,000 for new PMA transmissions.

Contact Comanche Gear

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