Tire wear

Your life is riding on those steers. I'd look at changing them and holding off on the drive tire if money is an issue. The alignment is a must. Have them check all of your bushings in the rear too. Otherwise, your alignment will be for nothing if there are bad bushings.

My 2 cents.

 

Agree
Alignment and bushings
And do not screw around with steer tires especially. If you want to run them out a little longer you can move them to drive or trailer tires if all the same size. As long as traction isn't an issue you can get away with it.

 

Just realized you said that one drive is nearly bald. Find a shop that sells used tires and get one that closely matches the others as far as tread depth is concerned. But DO replace the steers.

 

Find a good shop locally that specializes in truck suspensions and alignments so someone that knows what they are doing will check and look it over. It should be easy to figure out in about 15 minutes to a half hour of checking all wear components. Get it fixed ASAP then put new tires on. The vibration could be anything. Bad bushings. Out of round tire. Lots of things. You won't know until everything is checked. Don't waste your time and money at a T/A, Petro, Loves or some such other shop, those places are ok for changing tires but not much else.

 

That's worn like that from over inflation.

 

Can any one please help me with a little problem? I have a 1996 379 peterbilt with 425 cat motor its a 35 ton wrecker and when I pick up a truck or when I am on a small incline I go to take off and my truck starts hopping and jumping out of control.any clue what could be going on here.