Since frame-engaging lifts are the most popular style in light duty shops, here are some additional tips regarding their use:
- Never assume the lift swing arm restraints will keep the arms from coming out from under the vehicle. If the adapters aren’t placed on a flat, level surface, the horizontal force developed on the adapter pad can be greater than the vertical force applied to it. Swing arm restraints are only designed to resist 150 pounds of horizontal force.
- Take the adapter design into consideration. Does your lift have flip-up adapters, screw-type adapters or stacking adapters? Are the adapter surfaces steel or rubber? Are there features on the adapters that would inhibit lateral movement? Do you need to use extenders to prevent swing arm contact with sills, rocker panels, pipes, dams, steps or running boards?
- What about lifting on the spring hangers? Some vehicle manufacturers approve this in some cases. If you place the adapter on the spring hanger, does the spring rest on part of the adapter pad? If the leaf spring is on the adapter, the vehicle can walk right off of the adapter if it is rocked up and down. Due to the upsweep of the frame forward of the rear suspension on some long wheelbase vehicles, the front-most rear spring hanger may be your only practical choice, even though it is not ideal. If you select the spring hanger as the lift point, be sure the adapter is not supporting the vehicle on the spring itself and always use vehicle support stands.
- Never use blocks (wood or other materials) between the adapters and the vehicle lift points, even if the vehicle manufacturer recommends them. The use of blocks can only lead to instability.
- Never lift one end of a vehicle using only two swing arms of a swing arm style lift.
- If the adapter pads on the lift won’t reach the recommended vehicle lift points, use a different lift.
Let’s talk a little bit about vehicles lifted on the two-post, fore-and-aft, movable piston, wheel- and axle-engaging lifts. Some strange things are attempted on these lifts.
For example, a technician may lift only the rear of the vehicle to provide greater access to the front engine compartment. The concern here is that if the front wheels are free to roll on the floor, the horizontal forces applied to the rear jack are equal and opposite to the breakaway friction and rolling friction of the front wheels – which means the rear jack will be damaged. Chocking the front wheels only makes the situation worse. As the rear axle is lifted with axle adapters or, as the rear wheels are lifted with wheel adapters, vehicle stability becomes solely dependent upon the security of the engagement between the vehicle rear lift points and the rear lift adapters.
Another concern is when the front jack and the rear jack are set at different levels while supporting the lifted vehicle. This condition is potentially damaging to both the front jack and the rear jack. The out-of-level condition should be limited on any two-post, fore-and-aft, movable-jack, axle- or wheel-engaging lift to 3 degrees front to rear or, rear to front. In any case, the lifted vehicle should always be lowered onto the lift locks before the technician goes under the vehicle. As always, additional confidence may be gained by placement of vehicle support stands to enhance stability.
Your Safety Is Riding On It
If you think about what you’re doing and think several steps ahead, you’ll be your own best safety advocate. A little time spent thinking about the lift and the vehicle to be lifted can save your life.
ALI offers a number of lift safety materials. Member companies provide many of these materials with every new lift sold. They can also be purchased at the ALI Store at www.autolift.org. One popular resource is the Lifting It Right safety kit that includes a DVD hosted by Richard and Kyle Petty, the Lifting It Right safety manual, and a safety tips card to be posted on or near a lift.