Question:
Why are there different pumps for 2wd and 4wd?
I'm sure that 4wd is harder to move because of the added resistance of the 4wd components.
I'm guessing it's due to the fact that 2wd has rack and pinion steering, while 4wd still has the old recirculating ball steering box.
Even so.... the 2WD and 4WD pump are listed as the same application on Rockauto. Since the pump just supplies the fluid under pressure, it should work for both systems.
Here is the pump. 1999 - 2006 Silverado.
http://www.autopartswarehouse.com/d...QQPower_Steering_PumpQQ19992006QQA120661.html
Fit note: 4WD, Crew Cab Pickup, 4WD, Without Luxury Edition Package (Y91), Crew Cab Pickup, RWD, Extended Cab Pickup, 4WD, Without Luxury Edition Package (Y91), Extended Cab Pickup, 4WD, Without Off Road Package (9G3), Without Sport Package (B4U), Extended Cab Pickup, 4WD, Without Sport Package (B4U), Without Luxury Edition Package (Y91), Without Off Road Package (9G3), Extended Cab Pickup, AWD, Without Luxury Edition Package (Y91), Extended Cab Pickup, AWD, Without Sport Package (B4U), Without Luxury Edition Package (Y91), Without Off Road Package (9G3), Extended Cab Pickup, RWD, Without High Output Package (B4V), Extended Cab Pickup, RWD, Without Spring Special (B2E), Without High Output Package (B4V), Extended Cab Pickup, RWD, RWD, Standard Cab Pickup