I've had 2 Priuses 2010 lose the oil change door from the main protective panel under the car. Many have posted about this design flaw. My question is: Does the 2015 Prius also have this potential problem? I remember reading forum posts about the TSB regarding this issue on the 2010 which I was too late to take advantage of. I would rather address this now before my warranty expires on my 2015.
A few owners got the underpanel replaced; can't recall if there was any significant change with the new one. I've done all my own oil changes. With the first oil change I bent back that door. Well, tried to: couldn't believe what was happening, then entire panel was flexing, and it was obvious the plastic was too rigid to do this on an ongoing basis. From then on I've removed the entire panel at oil changes. Over 5 years, oil changes every six months, no problems. Also, have yet to need to replace any of the push-in fasteners. Whenever they're off, I wash them out with soapy water, sluice all the grit out of them.
I did replace mine. The new one had a different part # and the plastic "hinge" did seem a little "beefier." Like you, I've been removing the entire panel for oil changes to get a good look/see at everything else under there.
FWIW, the Toyota Repair Manual's description of an oil change makes no mention of the flap, says to remove the whole panel, AND the one ahead of it, which really makes no sense.
