I'm frustrated and can't think straight. 2006 Silverado Ext 5.3L, 4L65E (not original), 2wd Truck came with a 3.23 gear. I've been pulling a 6000 lbs trailer for 4 years. I just swapped a new 3.73 in, looking for a little more take off power. Now it feels like I have less take off than before, with the same trailer. At first I thought the trailer brakes were hanging. That has been ruled out. Am I just being to gentle because I just completed the break in or is there something else I'm missing? Help a dummy!