The oil filler cap won't come off my Jeep TJ and ratchets in the wrong direction.

According to the Jeep Service guy I talked to, the stock ratcheting oil filler caps usually break ater about ten oil changes. I guess I'm lucky that mine lasted 15 oil changes. The spring is strong enough to provide enough outward force to keep the male teeth engaging with the lower cap. The plastic eventually bends and allows reverse ratcheting.

Procedure:

  1. Buy a new oil filler cap from your favorite auto parts store. While a ratcheting cap is better to prevent overtorquing and damage to the cover, as long as you don't monkey-fist it, you should be fine with a non-ratcheting cap. Either way, they are all $7.00 or less.
  2. Pry off the upper half of the stock cap. See the tabs that hold the upper half to the lower half. Just pry around the edge of the cap, and it will come off with very little force. (A gloved hand should be sufficient)
  3. Use a wrench to loosen and remove the lower half of the filler cap.
  4. Install the new cap, and throw the old junk away.