How to Check and Top Up Your Engine Oil: A Complete Guide

Checking your engine oil level is one of the simplest maintenance tasks you can do yourself, but it is also one of the most important. Engine oil lubricates, cools, cleans and protects the moving parts inside your engine. Driving with too little oil can lead to excessive wear, engine noise, overheating or even serious engine damage.

Still, many drivers are unsure when to check the oil level, how long the engine should cool down before checking, how much oil to add and what to do when the oil level is low. In this guide, we explain everything step by step.

Looking for the right products for oil maintenance? View our range of engine oil, engine flush products and practical funnels for clean and safe refilling.

Why is the engine oil level so important?

Engine oil creates a thin protective film between moving metal parts inside the engine. These include the pistons, camshaft, crankshaft, bearings and valves. Without enough oil, metal parts can come into direct contact with each other, causing heat, friction, wear and eventually damage.

Engine oil has several important functions:

• Lubrication: reduces friction between moving engine parts.
• Cooling: helps carry heat away from critical engine components.
• Cleaning: transports dirt, soot and combustion residues to the oil filter.
• Sealing: helps maintain compression inside the cylinders.
• Protection: helps prevent corrosion, deposits and premature wear.

A low oil level means the engine may not receive enough lubrication. However, too much oil is also harmful. Overfilling can cause foaming, excess pressure or oil entering the intake system through the crankcase ventilation. That is why accurate checking and careful topping up are essential.

How to check your engine oil level

The best way to check your engine oil level is to park the vehicle on a level surface and allow the engine to cool down briefly. This gives the oil time to drain back into the sump, resulting in a more accurate reading.

1. Park on level ground: do not check the oil level while the car is parked on a slope.
2. Switch off the engine: wait a few minutes so the oil can return to the sump.
3. Open the bonnet: locate the dipstick. It often has a yellow, orange or red handle.
4. Remove the dipstick: wipe it clean with a lint-free cloth or paper towel.
5. Insert the dipstick fully: push it all the way back into the tube.
6. Remove it again: now read the oil level.
7. Check the markings: the oil should be between the minimum and maximum marks.

Some modern vehicles no longer have a traditional dipstick. Instead, the oil level is measured electronically through the onboard computer or infotainment system. In that case, follow the instructions in your vehicle manual.

How to read the dipstick correctly

Most dipsticks have two markings: MIN and MAX. These may appear as holes, lines, notches or a textured section. The oil level should always sit between these two points.

• Below MIN: the oil level is too low and must be topped up.
• Between MIN and MAX: the oil level is correct.
• Close to MIN: topping up is recommended, especially before a long journey.
• Above MAX: there is too much oil in the engine, which can cause problems.

Never add oil blindly. Always check the level first, add small amounts and measure again.

How long should the engine cool before checking or adding oil?

For an accurate oil level reading, it is best to wait around 5 to 10 minutes after switching off the engine. This allows the oil to drain back into the sump while the engine is still slightly warm. Slightly warm oil flows more easily, which often makes the level easier to read.

If you check the oil immediately after driving, some of the oil may still be circulating through the engine. This can make the level appear lower than it actually is. Checking the oil when the engine is completely cold, for example in the morning, can also be accurate as long as the car is parked on level ground. The most important thing is to measure consistently.

When should you avoid adding oil immediately?

Avoid adding oil straight after heavy engine load, such as a long motorway drive, mountain driving, towing or driving with a caravan. Let the engine cool down for a few minutes first. This reduces the risk of spilling oil onto hot components and helps prevent inaccurate measurements.

How to top up engine oil

Topping up engine oil is straightforward, but it should be done carefully. Always use the correct engine oil for your vehicle. The correct viscosity and specification can be found in the vehicle manual or manufacturer recommendations.

1. Check the oil level first: only add oil if the level is near or below the minimum mark.
2. Use the correct oil: choose engine oil with the right viscosity, such as 0W-20, 0W-30, 5W-30, 5W-40 or 10W-40, depending on your engine.
3. Remove the oil filler cap: this is located on top of the engine and is usually marked with an oil can symbol.
4. Use a funnel: this helps prevent spills on the engine, belts or plastic covers.
5. Add small amounts: start with 250 ml to 500 ml.
6. Wait briefly: allow the oil to settle into the sump.
7. Check the level again: use the dipstick and add more only if needed.
8. Close the filler cap properly: also make sure the dipstick is fully inserted.

For clean and accurate refilling, a 4-piece funnel set is very useful. It helps prevent oil from spilling onto hot engine parts, covers, hoses or belts.

How much engine oil should you add?

The amount of oil you need to add depends on the difference between the minimum and maximum marks on the dipstick. In many passenger cars, the difference between MIN and MAX is approximately 1 litre, but this varies per engine.

A safe approach is:

• If the level is slightly below the middle: add around 250 ml.
• If the level is close to minimum: add around 500 ml.
• If the level is at or below minimum: add around 500 ml, wait briefly and check again.
• Never add a full litre at once without checking the level in between.

Overfilling can be harmful. If the oil level is too high, the crankshaft may whip air into the oil, causing foaming. Foamy oil does not lubricate properly. Excess oil can also enter the intake system through the crankcase ventilation, which may cause smoke, contamination or engine performance issues.

What should you do when the oil level is low?

A low oil level should always be taken seriously. The right action depends on the situation.

1. Low oil level without a red oil warning light

If the oil level is low but there is no red oil pressure warning light, top up with the correct engine oil. Add small amounts, check the level again and avoid overfilling. After a short drive, check the oil level once more after the engine has been switched off for a few minutes.

2. Yellow oil level warning light

A yellow oil warning light usually means the oil level is low or the vehicle is asking for an oil level check. You may still be able to drive, but you should check and top up the oil as soon as possible. Do not keep driving unnecessarily.

3. Red oil warning light

A red oil warning light is serious. It usually indicates an oil pressure problem. Stop the vehicle safely as soon as possible, switch off the engine and do not continue driving. Low oil pressure can cause severe engine damage within a very short time. Check the oil level, but remember that topping up may not solve the problem. If the red light remains on, have the vehicle inspected by a garage.

4. Oil level keeps dropping

If you need to top up oil frequently, there may be oil consumption or an oil leak. Possible causes include worn piston rings, valve stem seals, leaking gaskets, crankcase ventilation problems, turbocharger wear or old and contaminated oil.

In some cases, a product such as Lindemann Engine Performance Treatment may help reduce friction and wear symptoms. For older engines or engines with noticeable wear, Lindemann Worn Engine Treatment may also be worth considering.

How often should you check your engine oil level?

A good rule of thumb is to check the engine oil level at least once a month. You should also check it before long journeys, holidays, towing, mountain driving or whenever the engine sounds different than usual.

Check the oil level more frequently if:

• You mainly drive short distances.
• Your vehicle has high mileage.
• You often drive with heavy loads, a trailer or caravan.
• Your engine consumes oil.
• You recently topped up or changed the oil.
• You notice oil stains underneath the vehicle.
• A warning light appears on the dashboard.

Do not wait until a warning light comes on. Many cases of engine damage occur because a vehicle has been driven too long with low or contaminated oil.

Which engine oil do you need?

The correct engine oil depends on the engine type, production year, manufacturer specification and emission system. Do not look only at viscosity, such as 5W-30 or 5W-40. The approval and specification are just as important. Modern engines can be sensitive to the wrong oil, especially engines with turbochargers, timing chains, particulate filters or start-stop systems.

At Dutch Performance Products, you can find various types of Lindemann engine oil for modern petrol, diesel, LPG and hybrid vehicles. Examples include:

• 0W-20 engine oil – often used in modern low-friction engines and some hybrid vehicles.
• 0W-30 engine oil – suitable for various modern petrol, diesel and LPG engines.
• 5W-30 engine oil – one of the most commonly used oils for modern passenger cars and light commercial vehicles.
• 5W-40 engine oil – suitable for many petrol and diesel engines, including vehicles under heavier load.
• 10W-40 engine oil – often used in older engines or engines with different specification requirements.

If you are unsure which oil your vehicle needs, always check the owner’s manual or follow the manufacturer’s required specification.

When is topping up oil not enough?

Topping up oil only corrects a low oil level. It does not solve contamination, internal wear, leaks or overdue maintenance. If the oil is very dark, thick, burnt-smelling or sludge-like, an oil change may be a better solution than simply adding more oil.

Watch out for these signs:

• The oil is extremely black and thick.
• There is sludge or mayonnaise-like residue under the oil filler cap.
• The engine ticks or rattles during cold starts.
• The engine consumes more oil than before.
• Blue smoke comes from the exhaust.
• The oil warning light returns after topping up.
• The engine runs rough or feels less responsive.

In these cases, you should look beyond simply topping up the oil. An oil change, diagnosis or internal oil system cleaning may be necessary.

Engine flush: when does it make sense?

An engine flush is a cleaning product for the oil system. It is added to the old engine oil before an oil change. The engine is then allowed to idle briefly, giving the cleaner time to loosen sludge, deposits and contamination. After that, the old oil is drained and replaced with fresh oil and preferably a new oil filter.

An engine flush can be useful in cases of:

• contaminated engine oil;
• overdue maintenance;
• frequent short trips where the engine does not fully warm up;
• ticking hydraulic lifters;
• sludge or deposits in the oil system;
• reduced lubrication due to contamination;
• an oil change where you want to clean the system more thoroughly.

Lindemann Oil System Cleaner is designed to clean the oil system thoroughly before an oil change. It is suitable for petrol and diesel engines and helps remove deposits from the lubrication system.

Important: be careful with heavily contaminated high-mileage engines. In some very old engines, deposits may have built up over many years. If you are unsure, seek advice before flushing or choose a product that better suits worn engines.

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Oil change or oil top-up?

Adding oil and changing oil are not the same thing. Topping up restores the oil level. Changing the oil replaces old, contaminated oil with fresh oil.

Common mistakes when checking or topping up engine oil

Many oil-related issues are caused not by lack of maintenance, but by incorrect maintenance. Avoid these common mistakes:

• Checking on a slope: this can give an inaccurate reading.
• Checking immediately after driving: some oil may still be circulating through the engine.
• Adding too much oil: overfilling can be just as harmful as low oil.
• Using the wrong oil: not every 5W-30 or 5W-40 oil has the same specification.
• Not using a funnel: spills can cause smoke, smell or contamination.
• Only topping up and never changing the oil: old oil loses its protective properties.
• Ignoring warning lights: especially a red oil warning light requires immediate action.

Useful products for engine oil maintenance

You do not need many tools to maintain your engine oil properly, but the right products make the job easier, cleaner and safer.

• Engine oil – choose the correct viscosity and specification for your vehicle.
• Lindemann Oil System Cleaner – engine flush for cleaning the oil system before an oil change.
• 4-piece funnel set – useful for spill-free refilling of oil, coolant or additives.
• Lindemann Engine Performance Treatment – helps reduce friction and wear and supports smoother engine operation.
• Car additives – for additional maintenance and protection of the engine and fuel system.

Quick checklist: checking and topping up your engine oil

Need a quick summary? Follow these steps:

1. Park the vehicle on level ground.
2. Let the engine cool for 5 to 10 minutes after driving.
3. Remove the dipstick and wipe it clean.
4. Insert the dipstick fully and remove it again.
5. Check whether the level is between MIN and MAX.
6. If the level is low, add 250 ml to 500 ml of oil.
7. Use a funnel to avoid spilling.
8. Wait briefly and check the level again.
9. Never fill above the MAX mark.
10. If the level keeps dropping, have the vehicle inspected.

Frequently asked questions about checking and topping up engine oil

Can I add oil when the engine is warm?

Yes, in most cases you can, but it is better to wait 5 to 10 minutes after switching off the engine. This allows the oil to drain back into the sump and reduces the risk of spilling oil onto very hot parts.

Can I mix different engine oils?

In an emergency, topping up with oil of the same viscosity and specification is best. Mixing different oils is not ideal. For regular maintenance, always use oil that meets the manufacturer’s required specification.

Is it bad if the oil level is slightly above maximum?

A very small amount above maximum may not immediately cause damage, but it is not recommended. If the level is clearly above MAX, have some oil drained or extracted.

Why do I keep having to add engine oil?

Frequent topping up may indicate oil consumption, leaks, wear, contamination or problems with the turbocharger, piston rings, valve seals or crankcase ventilation. If this happens often, have the vehicle checked.

How do I know which engine oil my car needs?

Check the owner’s manual, the label in the engine bay or the manufacturer’s specification. Pay attention to both viscosity and approvals, not only the number on the oil bottle.

Conclusion

Checking and topping up your engine oil is simple, but it must be done carefully. Park the vehicle on level ground, let the engine cool briefly, measure correctly and add oil in small amounts. Always use the correct engine oil and a funnel to avoid spills.

A low oil level can lead to serious engine damage, especially when a red oil warning light appears. Check your oil level at least once a month and always before long journeys. If the level drops quickly or the oil looks contaminated, topping up alone is not enough and further maintenance may be required.

At Dutch Performance Products, you can find everything you need for proper oil maintenance: from high-quality engine oil to engine flush products, Lindemann Oil System Cleaner and practical funnels for safe and clean refilling.