I have a 2005 Chevy Suburban 1500 4WD 5.3L with 187000+ miles. It has a really bad tapping/knocking sound. I think this is the infamous lifter knock, and was caused by infrequent oil changes and running low on oil about 100k miles ago.
I am planning to spray Berryman B-12 Chemtool into the lifters, and then run Motor Medic Motor Flush through the engine for 5 min, followed by an oil change.
The directions for the flush say that on high mileage engines to clean out the oil pan after the flush and before putting in the new oil. My Haynes manual says that to do this, I need to remove the front differential. This seems like quite an involved process, and I want to make sure this is advisable before I go down this road.
I consider myself a novice: I have changed my sparkplugs, replaced front suspension components (control arms, shocks, links, etc), changed the oil, etc. This would be my first time doing something like this.
If I go through this process (please comment on whether I should!), what else should I inspect/change while I have the oil pan off? Should I replace the gasket, oil pumps, etc?