I just did mine, on my 603. There the same, the one closer to the top just looks bigger because it has been streched for 15+ years. Mine were original as far as I know and were in ok shape. Changing them every oil change is probably overkill. I would say every 5 years sounds about right.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200