LS Piston Oil Drain Back Jig

thingiverse

Stock LS pistons have inadequate oil drain cutouts; The small notches on the outside of the piston are often blocked by the lower oil ring. Especially after high mileage, carbon buildup in the small oil returns can cause piston rings to stick in place, excessive oil consumption, and carbon buildup on the piston skirt. A common modification is to drill oil drain holes in the lowest ring grove above the piston skirt, which help return oil scraped from the cylinder walls back into the oil pan. This is a simple alignment tool I made to ensure the oil drain holes are evenly located on all pistons. Simply align the witness hole on the jig with the dot on the the top of the piston, mark the oil drain locations, and drill using a 7/64" (or smaller) drill bit. Compatible with all 4.8L/5.3L LS engines with a 3.78"/96mm piston diameter.