The average of allsubgroups becomes the centerline for the lower plotting area. Average of Ranges Example Step 7 - Calculate the upper control limit (UCL) and lower control limit (LCL)for the averages of the subgroups. At this point, your chart will look like aRun Chart. Now, however, the uniqueness of the Control Chart becomes evidentas you calculate the control limits.
Ford Motor Company recommends that the Crown Vic limit its towing to a trailer with a gross vehicle weight of 1500 lbs or less with a tongue weight not to exceed 150 lbs. See HERE.
Class 4-5 Receivers. These receivers are the heaviest-duty trailer hitches that can be installed at the rear of a tow vehicle. A Class 4 hitch can carry 10,000 pounds and 1,000 pounds of tongue weight with a weight carrying hitch, or up to 12,000 and 1,200 pounds with a weight distributing hitch.Class 5 receivers can carry up to 14,000 pounds and 1,400 pounds tongue weight.eight distributing hitches are used in the same Class 3-5 receivers as a weight carrying hitch. Any vehicle with a Class 3-5 receiver can use a weight distributing hitch. There are a couple of key differences between these units and weight carrying models.