I have a 2010 5.3L that has leaked a little oil for years, but recently it became quite bad. Oil was showing up all over the bottom and especially on the swaybar below the oil filter and the starter. I pulled the intake to check the oil pressure sending unit and cam sensor back there and they're dry. Since there was some oil around the manifolds, I swapped the valve cover gaskets. They were brittle and broke on removal. I pulled the starter to look at the crank sensor and it's dry. I pulled the front differential out and replaced the oil pan gasket. It was also brittle and broke apart in my hands. Looking in the starter hole and the torque converter inspection cover, it looks dry in there (so not rear main seal). It is leaking less oil, but we're still talking like a quart every 500 miles.
So is there anything left before pulling the transmission to replace the rear cover seal? At this point, the oil seems to be dripping only from the starter bolt. I will order the GM kit that includes the cover, gasket and rear main (12639250), unless there is a better option. Is it true no special tools are needed? It seems weird for all seals to fail at the same time. Maybe check the PCV system? I have older engines that never needed this. Is it from the truck sitting in Texas for many years?
So is there anything left before pulling the transmission to replace the rear cover seal? At this point, the oil seems to be dripping only from the starter bolt. I will order the GM kit that includes the cover, gasket and rear main (12639250), unless there is a better option. Is it true no special tools are needed? It seems weird for all seals to fail at the same time. Maybe check the PCV system? I have older engines that never needed this. Is it from the truck sitting in Texas for many years?