Serious vibration

Just rolled over 100K miles on 2014 Mack. Had a vibration and a couple bad tires on rear pull axle. Put new steering tires on and 4 pull axle tires. Still have vibration. Put 4 more on front axle, no help. Checked swing bearing and u-joints. All seem to be fine. Just for kicks I took a tape measure and measured distance from frame to outer wheel edge. On rear axle their is about 1/4 inch difference between left side and right side. Front pull axle their is 3/4 inch difference. I'm thinking this can't be right and probably causing vibration. Question is, how did it get this way and how do I fix it? Pull pulpwood. Rough roads in and out of woods.

 

Could be injectors, the Mack motors were notorious for eating them.
MP8?

 

MP 10. 455 HP. M Drive. I feel the whole truck shaking. Sometimes the steer tires.

 

Could be in rear itself.

 

Yes true

 

One inside pull tire was eaten up pretty bad. Had chunks out of it by the time I changed it. I'm afraid it's going to do the same thing to my new tires. Gotta find the problem.

 

Take it in to an alignment shop and see if rear axles are in alignment if its eating tires that bad shouldnt be hard to find by a reputable shop.

 

Jack: Your dog is barking up the wrong tree. The most mileage on rear drives I ever saw was on a Mack, over 300,000, at a company shop that did alignments on a schedule. The first one was worked on for days because the steer, front and rear drives all ran on a different center line from the frame. Found all the others were the same and off more than yours. Set up the front end and make sure the distance center to center of the drive axles is the same and the camel backs will work it out. You may not have camel backs but the offset still applies as long as all axles point in the same parallel direction your OK. Alignment does not normally cause vibration. Thank of out of round tires, budd rim or drum, on a hub pilot, with the clutch in or out, speed or RPM related, work done recently?

 

No work done. Truck has 104K miles, factory rims, no clutch, M-Drive transmission. 18 new tires. Sometimes vibration happens at 20 mph and sometimes at 60. Seems to smooth out at 70 mph.

 

Check the torque on all the suspension bolts. If something moved you'll see it when you're under there. Yes, it sucks, but I bought a 600ftlb torque wrench off a tug boat mechanic that paid for itself after the first use.