Macpherson Struts

Had to replace right front strut in 2006 (both of course) at 40K miles. Same one needs replacement at 74K. Is this normal for a car that’s maintained well; e.g., tires balanced twice/yr. & alignments; no offroad driving or excessive speed bump encounters? Could there be some manufacuturer’s defect that’s causing this? (it’s 4 cylinder automatic) We use a certified Toyota mechanic who uses Toyota parts. Thanks for any input.

Duplicate, go here http://community.cartalk.com/posts/list/2157596.page