Will a 1992 4.0 Ford Explorer motor and transmission fit in 1988 Ranger with 2.9?

No, a 1992 4.0L Ford Explorer engine and transmission will not directly fit into a 1988 Ford Ranger with a 2.9L engine without significant modifications. While both are Ford products, the engine bays, mounting points, and transmission configurations are different enough to make it a very complex and likely impractical swap. You'd be talking about major fabrication work including:

* Engine mounts: The 4.0L is a larger and heavier engine, requiring entirely new motor mounts.

* Transmission mounts: The transmission (whether automatic or manual) will also need new mounts.

* Driveshaft: The driveshaft will almost certainly be too short or too long and need replacement or modification.

* Exhaust system: The exhaust system will need to be completely replaced or heavily modified.

* Wiring harness: The wiring harness from the Explorer will likely need modification or replacement to interface with the Ranger's system.

* Cooling system: The cooling system may need upgrades to handle the larger engine.

* Steering components: Potential clearance issues may require adjustments.

The amount of work required would likely exceed the value of the Ranger, especially considering the availability of used 4.0L Ranger engines which are a much more straightforward swap. If you're aiming for more power in your Ranger, a 4.0L swap from another *Ranger* is a far more realistic project.