Autopsy on dead slide out motor/gearbox
A few weeks ago on our next to last night of our 3+ month trip the slideout motor on the living room drivers side slide crapped out. I could hear the motor running, but no movement in the slide. Got out the tools and loosened up the trans torque fittings and rolled the slide back in so we could travel. Since repair parts are not offered by newmar, I ordered a new motor/gearbox and installed. All is well. Yesterday I had some time so I took the old,failed unit apart.
What i found was one of the gear shaft roller bearings failed, allowing the gear shaft to wobble, causing it to bind and break a tooth and then jam which then caused the PLASTIC gear that is driven by the motor to be stripped of teeth resulting in the motor just spinning.
For a low speed, high load application I would have thought bronze bushings would have been a better choice. And the use of a plastic gear is questionable. Sure, it could protect the rest of mechanism by stripping out the teeth , but why, since there are no replacement parts available anyway. I would think a better way would be to have a metal gear and shear pin.That way, the user could repair it, if needed. Anyway, the culprit was the roller bearing. You can see in the pic, the only thing left in place was the outer ring, the rollers scattered about and the cage was busted up. Here's a few pics showing the remains of the bearing, a couple rollers, the chewed up plastic gear. ... and it was only $1129 to buy a replacement unit.
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2013 DS 4338
2015 F-150 toad with kayaks,bicycles and a Harley in the back
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