Re: Oil pan removal
On the jeep 4.0L inline six, dropping the oil pan is a bit of a task.
Step 1 Disconnect battery negative terminal.
Step 2 Remove oil dipstick and put in safe place.
Step 3 Raise vehicle and mount on 4 jack stands.
Step 4 Remove oil sensor (if equipped)
Step 5 Remove plastic shield from bottom front of engine.
Step 6 Drain oil and replace oil filter.
Step 7 Disconnect exhaust pipe at back of engine.
Step 8 Remove starter motor.
Step 9 Remove the flywheel inspection cover from back of oil pan.
Step 10 Use floor jack with 2x6" wood on top and lift engine from vibration dampener just enough to relieve pressure from motor mount bolts.
Step 11 Remove the motor mount through-bolts to lift the engine.
Step 12 Lift engine as high as it will go safely still using 2x6" wood on top of floor jack
Step 13 Take new pan gasket and large piece of cardboard. Stencil around gasket and poke inside gasket holes with pencil through cardboard.
Step 14 Remove oil pan bolts and studs one at a time, degrease and clean them, then place in corresponding hole on cardboard stencil.
Step 15 Remove oil pan. You may need to use soft mallet and flat putty knife to break free. Slide out pan to the rear.
Step 16 Carefully remove all gasket residue from bottom of engine and oil pan. Careful not to gouge aluminum timing chain housing.
Step 17 Inspect inside of oil pan for metal specks or debris. (These engines are very well built. At 150,000 miles my 4.0L oil pan was visually clean). Wipe clean inside of pan.
Step 18 Insert round flat magnet (from Radio Shack) inside pan near drain (lowest part of pan) This will collect iron fragments from oil.
Step 19 Using methyl ethyl ketone or acetone, wipe clean all mating surfaces for new oil pan gasket.
Step 20 Apply RTV sealant as recommended by gasket manufacturer. make circles around all holes. Use extra sealant where rubber meets cork.
Step 21 Replace the 4 alignment studs in their corresponding holes. Replace nuts if removed. (earlier models may not have studs) Hand tighten.
Step 22 Place dab of RTV on all bolt threaded ends and install all 1/4" diameter bolts. Hand tighten.
Step 23 Place dab of RTV on all bolt threaded ends and install all 5/16" diameter bolts. Torque to 156 inch pounds.
Step 24 Torque all 1/4" diameter bolts and nuts to 120 inch pounds. Start from a middle bolt, then across, making an outward spiral pattern until done.
Step 25 Recheck all bolt torque, check oil pan drain bolt for tightness. Inspect for bulging gasket material (especially at front aluminum housing) Correct if needed.
Step 26 Allow several hours for gasket material and sealant to set. Over night is best.
Step 27 Refill oil and check for leaks. Correct if necessary.
Step 26 Do reverse of Steps 10 down to 1.