I opened up a Fram Extra Guard to see how well the leaf spring sealed against the fiber end cap here:
https://bobistheoilguy.com/forums/t...-test-in-canister.386911/page-19#post-7008668
Even with a flat leaf spring and fiber end cap, the seal is not perfect, but it is far better than the rippled leaf springs.
https://bobistheoilguy.com/forums/t...-test-in-canister.386911/page-19#post-7008668
Even with a flat leaf spring and fiber end cap, the seal is not perfect, but it is far better than the rippled leaf springs.