I myself have a 98’ 4.0, 5speed, 4x4. My buddy just blew up his 07’ 4.0, 5speed, 4x4, and I bought the truck from him because the body is way better than mine. Anyways, I was wondering how hard it would be to swap my 4.0, Tranny, and Transfer case into the 07’ Ranger.

 

Mechanically it's a bolt-in swap, so that part would be easy. (Same engine mounts, essentially the same transmission and transfer cases, etc.)
BUT: You'll likely need to swap over all the harnesses, ECU, PATS, etc from the '98 and do a bunch of rewiring. In short, it would be a ton of work for questionable results: I mean you gotta love the old 4.0 OHV (my '99 originally had one too) for its low end torque and reliability but other than that it's really gutless -- the SOHC is the one you really want!

For arguably less work and a lot less hassle, search car-part.com for a good used 4.0 SOHC (there are loads of them around for cheap money), swap it into the '07. Then sell your '98 and you'll come out on top $$-wise in the end AND have a much more fun truck to drive.

Just my $.02, good luck!

 

+1 ^^^^

Welcome to the forum

The 1998 4.0l is an OHV engine, 2007 is a 4.0l SOHC engine, has 45 more horse power than the OHV so its a downgrade

In 2004 Rangers went Full Digital for cab wiring, this means the cluster and computer were a Matched Set, have to be used as a pair
Also many module differences
So ALOT of rewiring would be required because the 4.0l SOHC computer can't be used with the 4.0l OHV engine, and the 1998 computer can't be used in the 2007 as is


As amacadams said you would be way way better off buying a 4.0l SOHC replacement engine for the 2007 Ranger, and maybe selling your running 1998 Ranger as is