There have been reports of loose intake bolts on some of the 90’s 4.0L’s.

Check:

  • Check for loose lower intake manifold bolts.
  • Pull your #5 plug and check it out. If you see the fuzzy head or have some oil present around the sides of the plug, then bingo.

The 1993-1994 have this problem very often. Usually, you can fix it by simply tightening the bolts (in the proper sequence) and torquing to 21-25 Nm (15-18 ft lb), but sometimes you need a new gasket.

Do you notice a loss of oil with no leaks? Say 1-quart every 1500-3000 miles?

This is a simple fix…you will need the following:

  • 1/4″ Socket Drive
  • 6″ extension
  • Short wobble adapter (the broken neck socket adapter)
  • 10mm socket

Follow the pictures below for the location and proper tightening sequence. Most should be able to solve the problem by simple tightening, but some may need to replace the entire gasket as it may be shot. Make sure you follow the sequence for tightening!

Ford 4.0 OHV intake install diagram

Ford 4.0 OHV lower intake manifold bolt tightening sequence

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Jim Oaks is the founder of TheRangerStation.com, the longest-running Ford Ranger resource online since 1999. With over 25 years of hands-on experience building and modifying Ford Rangers — including magazine-featured builds like Project Transformer — Jim has become one of the most trusted authorities in the Ford Ranger off-road and enthusiast space. In 2019, he was loaned a Ranger FX4 by Ford Motor Company to test and document across the TransAmerica Trail. Jim continues to inspire and guide Ranger owners around the world.