Hey i have a 2000 GMC Sonoma Zr2 susension extened cab short bed. Well Every time i back up and turn the wheel to go in a parking spot my steering wheel gets tight. I have to hit the throttle a little and it will some how break away from being hard to steer then it goes back to being hard again. I have repalced the Power steering pump with an advance pump and blew the seal in it and the hard steering returned. So i took the advance pump out and put a ac delco pump in and a new gm gear box. This made the truck drive real smooth but just the other day the hard steering came back. I want to no if anyone has this problem and if they have found away to cure this hard steering thank you.  

My first guess would be it's not the pump, it's something binding up. Have ya checked every joint? steering column, tie rod ends,etc? Is the truck lifted or otherwise modified?  

Have you checked to see if it in 4wd?? This can cause steering to tighten up a lot in a turn because the wheels cannot turn at different speeds needed and would feed back into steering.  

Well i have the new school push button 4wd set-up i miss the old school when you had to shift your truck into 4wd. I really dont think the truck is in 4wd beacuse the 2wd light is lited up and i cant feel the 4wd when i go back on the trail i have to put it in 4wd cause it starts to get stuck but you no with this new technogly who noes it may be thats it's in 4wd thanks. When i bought the truck it had 100,000 miles on it which meant it was due for a front end. I have replaced the front tie rod ends, pittman arm idler arm upper control arm the works. I dont no if it can be that but i would have to check it out. Do you think it can be in the Gear box..???? have you guys ever had this problem in you chevy's or gmc's. Is this normal cause my other buddy has a 1999 sonoma that locks up at under 5 mph and trying to turn. This just blows..  

never heard that one. new ps pump, new gear box, tie rods, etc. and you're on the 3rd ps pump? I still have to wonder if the truck has been lifted and something is binding up. Does it have a body lift by chance?  

Does it have automatic 4x4 drive or just push and pray 4x4 drive?  

well i have the push and pray 4wd haha. Um the only lift i no is the factory 3 in lift. thats it. I didn't want to lift it any more then that cause it's such a small truck and to lift it you would have to make everything bigger i get that.. But this really does suck. When i back up and make a sharp turn it give me resitance and the wheel will kinda lock up right now i'm around 1500 rpm but when i touch the acclerator and pump it up to 2500 rpm and the wheel kinda then makes the turn. then it locks up all over again  

If you have thoroughly inspected every joint for free and uninhibited range of motion, double checked the ps fluid level, no leaks, it's got a new gear box and it still hangs up yer runnin out of options. You might try to pop off the pitman arm and see if the wheel turns free when youre not pushing wheels back and forth. Try to get a priest to annoint it with holy water.  

i have a 2000 zr2 and my truck does exactly the same thing i have not been able to figure it out when im working the truck really hard though the power steering is like its not even there at all ive asked dealerships about it i got the standard nothing wrong with it so i learned to live with it  

are ya sure ya have power "stirrin" fluid?  not something else by mistake? i'm not tryin to insult yer intelligence, i'm just saying yer not breedin pandas here. only a few things it can be, it's not a complicated system, right?