When cranking the steering wheel on a 2001 4WD (while in 2WD) to either extreme, the front end feels like it does when trying to turn sharply with 4WD engaged (in other vehicles, I haven't had the Blazer in 4WD yet.) It gets a bit jumpy.

Is this normal? Is something broken or worn?

 

it is most likely in 4wd and you don't know it. my blazer was in 4hi for a few days before i knew that my switch was telling my wrong. you should make sure it is not in 4wd. disconect the thing under the batterie and that should tell you or not

 

Right now it looks like the vacuum actuator is getting no vacuum ... how could it be in 4WD if the actuator's not engaging it?

 

The cable rusts up pretty good and freezes. If it was up north (which I assume it was based on your username) and parked over night while engaged in 4x4...it could very easily rust and stick in the engaged position.

Take out your battery, get to the vacuum actuator, get some pliers/vice grips on the cable, and give it a pull..or a push...see if it moves.

You might also want to check the tie rod ends, and the balljoints. They can give a bad ride in sharp corners if theyre on their way out.

 

Yeah, NH/PA vehicle prior to now.

I was checking out the actuator yesterday as I troubleshoot the flashing 4HI/4LO issue, the cable appears to move fine. Just in case I hit it with some of the lubricating+penetrating liquid wrench, range of motion didn't seem to change.

Tie rods and balljoints are probably original, I was planning on probably having to do balljoints sooner than later. Thing is though, this is only at low speeds, only sharp turns, and feels JUST like (to my recollection) 4WD lock/hop.

Guess we'll see how it feels after I get the vacuum switch to replace the dead one on my firewall right now, and can actually engage 4HI/4LO.

 

You know, 4WD may have been engaged or partially engaged after all ... since fixing the 4WD selector with a new vacuum valve and making sure the vacuum actuator actuates fully, the only real issue I seem to have with steering (other than a fair amount of play, but not horrible, will do front end rebuild eventually) seem to be power steering pump issues low power at low speeds/tight corners. No longer feeling 4WD lock/hop in the front end.

 

Good deal!