Can you take a 3.0 V6 out of a 88 4runner and swap it with a 4 cylinder? What kinda mods would you have to make?
If you are trying to save on fuel, this swap will only decrease the mileage, and cost you more than you intend to save on fuel. A 4 cylinder, pulling a heaver vehicle, will work harder and consume more fuel. If you have the cash, time, tools, and modifications,... anything can be bolted/welded/machined in to place.
88 year model has 2 engine choices, 22r (2.4 l4) and 3vz (3.0 v6), you can swap the engine and the transmission together. The 4 cyl engine is more reliable. However, smog is a different animal. If you plan to use for offroad only,upsize to a 3.4 is a better choice.
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