Service of the landing gear transmission should be done at annual and is covered in section 6-44 of the PA24 service manual. Lubrication and inspection is key. The dura transmission pictured above is lubricated with MIL·G·23827 (Aeroshell 7) and the dukes transmission requires the Dukes lubricant. (see here on instructions for making your own) Special attention must be given to the end play and security of the transmission bearing and lead screw end play. If either of these are out of tolerance the transmission must be replaced. New transmissions are nearly impossible to find and serviceable used ones are also pretty rare. An owner-produced option is likely your best bet. Matt Kurke at www.comanchegear.com is the expert and has a better than new owner produced option. You might also discuss with your A&P/IA an owner produced repair of your existing transmission. Since there is no approved repair procedure not all AP/IA’s are comfortable with this option.
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