I'd be careful with those aftermarket "power chip" boxes. Most of them are fake or do little, the ones that do something can have dangerous side effects. Case in point...on a diesel it may just increase the wastegate opening point which will allow more boost from the turbo and therefore more power, but at the added expense of heating up the turbocharger more and possibly causing other problems nobody thought of when they made that "power chip" and started marketing it on Ebay.
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'88 Pathfinder: 6" of lift, 33x13.50 Swamper LTB's, Rancho 9000's, L&P Stage 3 steering system, K&N, Pacesetter headers and 2.5" exhaust, Lock-Right locker, 110A alty and electric fan swap, dual batteries, 700W+ worth of PIAAs, etc.