So every time I go under the bus, I jack from the jacking plates on the axle. I take cribbing with me so there is something to hold her up if something should go wrong. I also crib up the axle. I just got finished with new wheels, drums and brake linings and I blew out an airbag. So how do I jack up the body to get in between the axle and frame? (1962 PD4106)
Jack it up normally under the axle, crib and remove tires.
In the maintenance manual, the body support points are illustrated.
Remove axle cribbing and crib under the body support points.
Lower the axle to settle the body on the cribbing, lower the axle further as required to access/re and re the air spring.
You already know to crib the axle while doing the work.
(Safety first: Jacks are to lift/lower, Jacks are NOT for holding things up while we work)
reverse course.
happy coaching!
buswarrior