Will a jeep 4.2 motor and 4.0 interchange?

Answer 1

Jeeps have the distinct honor of probably having the most engine options thatn any other vehicle. Maybe because Jeep owners in general like to fiddle around. So the 4.0 should swap easily in place of the 4.2 relative to other swap options. So while it is not totally direct- I am assuming you want to replace the 4.2 with the 4.0. There will be some conversions depending on what year & transmission in your current one. The computer will need to stay with the engine so if you get a 4.0, get the computer & wiring harness also. Then the bell housings may be different but they may be the same so check that. Then the clutch may or may not be the same. Different year Jeeps have different transmissions & Xfer cases so all that neds to match. The engines I believe are the same in length so that is a good thing. Go look at Jeep blogs & I am sure you will find some blogs from people who have done it & give you a better idea what obsticles you may encounter.