Should Engine Flush Be Used Before an Oil Change?

[Sylvia]

Engine flush should be used before an oil change. When changing the oil, purchase a bottle of engine flush additive, add it to the engine, let it idle for a few minutes, then drain the old oil before adding new oil. Otherwise, residual oil can reduce the effectiveness of synthetic oil. Engine oil, also known as engine lubricant (English name: Engine-oil), serves multiple functions for the engine: lubrication and friction reduction, auxiliary cooling, sealing and leak prevention, rust and corrosion protection, as well as shock absorption and cushioning. Below are the key functions of engine oil: 1. Friction Reduction: A sufficiently thick oil film separates the surfaces of moving parts, thereby minimizing wear. 2. Sealing: Engine oil forms a seal between piston rings and pistons, reducing gas leakage and preventing contaminants from entering. 3. Rust Protection: Lubricant adheres to part surfaces, shielding them from water, air, acidic substances, and harmful gases. 4. Shock Absorption: When cylinder pressure surges suddenly, intensifying the load on pistons, piston rings, connecting rods, and crankshaft bearings, the lubricant distributes this load, cushioning the impact. 5. Cleaning: High-quality oil carries away carbon deposits, sludge, and metal wear particles from engine components back to the oil pan, flushing contaminants from part surfaces through oil circulation.

[HectorLynn]

I don't think engine flush is absolutely necessary before an oil change—it depends on your car's condition and personal habits. My car has been running for over five years, and I rarely use flush additives during oil changes unless I notice sluggish engine starts or sudden fuel consumption spikes. In those cases, it does help remove some carbon deposits and improve new oil flow. But honestly, for new cars or well-maintained vehicles, flushes are mostly useless and just waste dozens of dollars. It's better to spend that money on premium oil instead. For older cars with severe carbon buildup, a flush might extend engine life and reduce failure risks. I mostly drive on highways to avoid frequent short trips, which naturally minimizes deposits and makes oil changes easier. Bottom line: don't blindly trust flushes—check your car's condition first.

[SanJoshua]

From a cost-saving perspective, I recommend not casually adding engine flush before an oil change. That stuff isn't cheap - a bottle can cost 30-50 yuan, plus additional labor charges for the oil change. If your car doesn't get driven much or is well-maintained, the engine internals will be clean enough that using flush is just wasteful. Last time I changed my oil, I skipped the flush step completely - the oil passages remained smooth as new and the engine had no issues. Of course, if your car is older or frequently driven in stop-and-go traffic with more carbon buildup, using a flush can help remove old oil residue and potentially prevent oil pump clogging, but that's a special case. For regular maintenance, honestly just changing the oil is sufficient - it's more reliable to consult with your mechanic for advice.

[LaRemington]

The function of engine flush is to dissolve carbon deposits and old oil impurities, making the oil change process more thorough. However, for new cars or well-maintained vehicles with strong self-cleaning capabilities, it's unnecessary. I understand some people prefer using it to prevent carbon buildup, especially after long-distance driving, but over-reliance can backfire, potentially diluting the new oil or causing waste. The truly effective approach is to choose a quality oil brand and adhere to regular oil change intervals, keeping the engine naturally healthy. Simply put, engine flush is the icing on the cake, not a necessity—judge based on actual needs.

[VonChloe]

Safe driving is quite important, and I believe changing the engine oil is a must-do regularly, but using a cleaner is not a standard preventive measure. A cleaner engine can reduce unexpected failures, such as avoiding a breakdown on the highway due to clogged oil passages, where a cleaner might help a bit. I've been driving for ten years and always pay attention to maintenance details. Before an oil change, I listen to the engine sounds and only consider adding a cleaner if there's an abnormality—otherwise, I just replace the oil directly. Combining fuel efficiency and convenience is better, as excessive cleaning can waste resources. I recommend checking the oil dipstick frequently to ensure high-quality oil, keeping the engine naturally smooth and durable.

[StWalker]

From a maintenance and environmental perspective, I prefer to use engine cleaners sparingly to reduce chemical pollution and waste oil disposal issues. An oil change itself removes most impurities, and if the car is well-maintained, adding cleaners can actually add unnecessary burden. I usually opt for high-performance synthetic oils and regularly check oil quality, which naturally keeps the engine clean. If carbon buildup becomes significant, I consider professional maintenance rather than blindly using additives. This saves money, is more sustainable, and gives me greater peace of mind while driving.