Why does the engine shake after an oil change?
2 Answers
Engine shaking after an oil change is due to high oil viscosity, increased mechanical resistance, and higher cylinder pressure. When selecting engine oil, pay attention to the following factors: 1. Choose engine oil based on the requirements of your engine. 2. Try to select multi-grade oil. Multi-grade oil offers advantages such as fuel efficiency, long service life, and high performance, providing better protection for the engine. Due to the characteristics of multi-grade oil, you may observe premature darkening or lower oil pressure compared to conventional oils, which is normal. 3. Some domestic engine oils are of quite good quality and are significantly cheaper than imported counterparts, making them a reliable choice. 4. If the engine is in good condition and the seasonal temperature is low, use oil with lower viscosity to ensure smooth oil flow. In high-temperature seasons or when the engine is severely worn, opting for higher viscosity oil helps form an oil film and reduces engine wear.
Engine shaking after an oil change may be caused by incorrect oil quantity or type. I've found some repair shops might use the wrong oil grade, such as oil that's too thick or too thin, leading to insufficient engine lubrication and causing shaking. If too much oil is added, excessive oil pressure can overload components; if too little is added, inadequate lubrication increases friction between parts. Another common issue is improper installation of the oil filter—a loose seal can allow air into the system, creating bubbles that disrupt oil flow. This results in unstable engine operation. I recommend immediately checking the oil level on the dipstick to ensure it's between the minimum and maximum marks, and verifying that the oil type matches the vehicle manual. If the shaking persists, return to the shop promptly to inspect the filter and overall system. Ignoring this could damage engine bearings or pistons, increasing repair costs, so don't delay addressing it.
