Neglecting to change your car's oil is about the worst thing you can do for your engine. Motor oil is the lifeblood of your car, cleaning out debris and particulates as it circulates through all the pipes and crevices of your engine. So having fresh oil is vital. Go tens of thousands of miles without changing it, and really bad stuff can happen.
Here's the proof. The I Do Cars YouTube channel got the opportunity to tear down a 2.3-liter EcoBoost inline-four taken out of a Ford Ranger with 104,000 miles on the clock, filming the entire process for a long-form video.
Evidence of neglect appears early on. The timing chain cover is covered in varnish, a tell-tale sign of old, overused oil. Removing the valve cover reveals a level of sludge and debris that could only come from a lack of oil changes.
Things get worse as the channel's host, Eric, digs deeper into the engine. There's a thick layer of sludge sitting at the bottom of the oil pan, and more varnish on the block, the oil pump, the camshafts, and the crankshaft.
Eric suspects whomever worked on this engine last dumped a bunch of oil-flush additive into the motor in an attempt to clean out the sludge. That had the opposite effect, loosening the sludge and clogging it in several of the engine's tiny oil passages.
That, according to Eric, is what eventually starved the engine of oil and caused it to spin a rod bearing. The damage was so bad that one bearing fused itself to the crankshaft, partially disintegrating.
After disassembling the engine, Eric references the Ranger's CarFax, which reveals no evidence of oil changes for the past 50,000 miles. So it's possible this truck was running on the same oil for the entire second half of its life.
Take this as a lesson. Please change your oil.
