Damper Strut

Check for oil leaks.
Move the piston rod up and down to check that it operates smoothly without any hitch.
Piston rod play
Measure the play as follows:

Fix the outer shell in place and fully extend the rod. Set a dial gauge at the end of rod L [10 mm (0.39 in)], and then read the dial gauge indication P1 while applying a force of W [20 N (2 kgf, 4 lb)] to the threaded portion. Apply a force of 20 N (2 kgf, 4 lb) from the opposite direction of "W", and then read the dial gauge indication P2.

Fig 1: Measuring Play
Courtesy of SUBARU OF AMERICA, INC.

Play limit

(P ₁ + P ₂ ):

0.8 mm (0.031 in)

If the play exceeds limit, replace the strut.