This Stillen pulley replaces the stock crank pulley with a smaller diameter and lighter weight unit. The belts are driven more slowly, diverting less power from the wheels. I side benefit is longer accessory life. These pulleys are not recommended for use in extreme conditions of where electrical requirements are high (like some of your 10 million watt stereo systems!). Instructions included, and the alternate belt listed must be used. 84-87 Turbos come in black only, 90-96's come in black, blue, or red. Specify model and color when ordering
You drive a truck :twak
Trucks have bigger tires, Spin the PS pump slower and watch your arms get bigger when trying to turn the wheel :banghead
If you ever off road :twak
Your Fan and Water pump will now go slower. Spin them slower and you'll Drive on the trail for 15minutes, then sit for 30 waiting for the truck to cool down to acceptable levels.
I bought a smaller crank pulley and did notice a minute difference in power, but mostly in the upper RPMs. After about 1,000 miles, I took it back off because (1) my battery went bad and (2) the power steering was not real predictable--but mostly bad when off roading or in a parking lot. I don't recommend the pulleys.
I've got a failry new pulley for a 5.0 and belt for it (with A/C) too that I don't need.