Frequently Asked Questions
Find a simple answer
Here you will find some of the most common questions we get asked here at Opie, ranging from oil advice to general order information.
What do you base your recommendations on?
We use a combination of industry leading databases, knowledge accumulated over several years, customer feedback and chemical analysis performed by a very experienced and respected oil chemist.
I can't find an oil I'm looking for on your site, can you get it for me?
We don't deal with all oil manufacturers, but we are often able to get alternatives to oil you are looking for. Just ask us if you can't find what you're looking for and we'll be happy to help.
Why is one synthetic oil so much more expensive than another?
There are three types of synthetic oils, Hydrocracked, Polyalphaolefin (PAO) and Ester oils. Hydrocracked oils are not really synthetic at all, they are highly refined and modified mineral oils that due to a court case can legally be sold as synthetic oils. All cheaper oils and the 'synthetic' component of semi-synthetic oils are hydrocracked mineral oils.
PAO synthetics are genuine, lab-made synthetic oils that are better lubricants than hydrocracked oils as they are built for their specific use, rather than the hydrocracked oils that are modified to perform a purpose.
Ester based oils are the top end of oil technology and give the best protection available. The ester content (usually ester oils are mixed with PAO oils) has several functions that are very useful. Esters are electrostatically charged so they stick to metal surfaces, meaning that when the vehicle is started, there is already a layer of oil present. They are also more stable at higher temperatures, making them ideal as performance lubricants. The ester content also helps to make those oils better lubricants in general.
Is it okay to mix oils?
In general, yes. There are a few exceptions, Castor and plant based (as used in some biodegradable oils) are not safe to mix with conventional oils. Other than those few exceptions, mixing oil brands, types (synthetic, semi-synthetic and mineral) and viscosities is fine. The only problem with mixing oils is that the quality of the better oil is diluted by the lesser one.
Do I need a diesel or petrol oil for my car?
There isn't really such a thing. If you look at the specifications listed on an oil, there should be an ACEA A and B specification, the A refers to petrol engine specifications and B to diesel. You will see that the numbers next to the letters are either the same or very close, meaning that the oil is suitable for both types of engine.
In the case of cars with diesel particulate filters (DPFs/FAPs), they will often need an oil that meets an ACEA C specification, which relates to low ash oils. The use of oils that do not meet the correct ACEA C specification can result in the particulate filter becoming blocked, an expensive repair.
Many car manufacturers have their own specifications and as long as the oil meets the relevant one, there is no need to consider the ACEA specifications as they will be part of the manufacturer ones.
How often should I change my oil?
The life of the oil is dependant on many factors.
Full synthetic oils last longer than semi-synthetics or mineral oils, so although they may cost more in the first place, a full synthetic can work out as a cheaper option in the log run. Many cars specify the use of full synthetic long-life oils and these may last over 20000 miles or up to 24 months.
If the car is used on track, the oil is subjected to far harsher conditions than motorway use. That may mean that a good track oil will have broken down sufficiently to need changing after 10 hours of use, whereas the same oil would be good for over 100 hours of use on motorways. Short journeys are very hard on the oil as it does not get the chance to get warm and flow properly as well as acceleration and deceleration making the engine work harder. Motorway use is the easiest condition for oil, the speeds are fairly consistent and rarely push the engine hard, there is plenty of air flow to help cool the engine and the oil has a chance to get up to temperature and flow properly.
Certain engines suffer from fuel dilution and that is one of the quickest ways that an oil can breakdown.
Should I use an oil additive?
Generally the answer is no. Most aftermarket oil additives are either useless, harmful or sometimes both. The technology used is often out of date and the products are made incredibly cheaply. If those sorts of additives were any good, the major oil manufacturers would be using them.
The only additives we sometimes advise using are the limited slip differential friction modifiers, for certain differentials.
My engine burns oil, should I use a thicker one?
It depends on the engine, what sort of use it gets, how much oil is being used and type of oil being used.
Certain engines really prefer a specific grade of oil to operate optimally, others aren't so fussy. It's best to ask us if you aren't sure if your car can use a range of different viscosity oils.
Most car manufacturers consider it acceptable for an engine to burn a litre of oil every 1000 miles or in some cases, 1000km. While topping up the oil at that frequency may be annoying and possibly expensive, there is generally nothing to worry about.
Using a full synthetic oil may help to reduce oil consumption if a mineral or semi-synthetic oil is being used. Mineral based oils consist of a mix of different sized molecules and the smaller ones can evaporate and then burn relatively easily, increasing the rate of oil consumption. The molecules in synthetic oils are uniform, so they are less likely to evaporate and burn.
My car is only being used on the road, do I need a full synthetic oil?
It depends on the car. Certain manufacturers specify that oils must be synthetic to meet the warranty requirements, so by using a more basic oil, your warranty can be invalidated
If you car has a diesel particulate filter, all the oils that meet the ACEA C specifications are synthetic and by not using one of those, the filter will become blocked.
If a car requires a 0w-x grade of oil, then it must be a genuine synthetic oil as it is impossible to make an 0w viscosity oil from mineral oils.
Even in cars that do not need oil that meet the above criteria, most of the time a synthetic oil is a preferable option as they give better protection and last longer. This is very relevant in engines used on track.
Will using a certain oil help my engine to make more power?
When a top quality oil of the correct viscosity is used, a vehicle may actually have a higher power output at the wheels than with other oils. The 'gain' in power is actually a reduction of the power lost in the engine. Internal resistance due to pumping losses and viscous drag and friction is where power is lost and minimising those will lead to more efficient running. Using a good oil reduces the friction as well as increases the protection.
A common approach to lubricating a powerful engine is to use as thick an oil as is available, but that adds to the internal resistance as the engine has to work harder to move the oil. That can also lead to increased wear in the engine as the oil does not flow as well as the engine would like. Often an increase in the quality of the oil used rather than the viscosity will be sufficient for many modified cars and that will actually give better protection as well as a slightly increased power output.
What colour is oil?
Automotive oils are naturally clear, not the amber colour that people assume they are. The reason they are often amber coloured is due to a dye manufacturers add and is only added as people assume oils should be a certain colour.
There are many oils on the market that are various colours and it is due to the addition of different coloured dyes. The dyes have no actual benefit to the oil, other than making it stand out as different to the rest.
Why does my oil turn black?
As well as lubricating an engine, another important feature of oil is that it cleans, removing combustion by-products from the engine and keeping them in suspension in the oil. This prevents the by-products from settling and building up as deposits in the engine.
Should I use an oil flush?
There is no need to flush the engine and flushing can be harmful. What can happen is the flush can loosen harmless deposits in the engine, but then not remove them. Your new oil goes in and after it gets warm and is flowing nicely, the bits which are loosened come off into the oil, so you end up with hard bits floating around in your oil - the last thing you want. If you really want to flush the oil system, the best thing you can do is drain out the oil that is in there, put in some basic mineral oil and run the car for a short while so the oil gets nice and warm. After running it, drain out the mineral oil and put in the correct oil.
What oil should I use to run in an engine?
A basic mineral oil should be used for running in as friction between the piston rings and cylinder linings is needed to allow the engine to bed in properly. If a synthetic oil is used, it prevents sufficient friction being generated and can lead to the bores becoming glazed. That causes a loss of power and increased oil consumption.
My garage recommends a brand of oil in my car, you recommend something different
So is our recommendation safe to use? Yes, absolutely. Garages often only stock one brand of oil, so they suggest that you should use that, but as we stock several brands, we often have something from a different manufacturer that will be as good if not better than the oil the garage uses.
Are your filters any good?
Yes is the simple answer. All of the filters we sell meet or exceed the manufacturer (OEM) specifications, so they are as good if not better in performing their function than the ones the manufacturer supplies.
Do I get a sump washer with the filter or service kits?
This depends if the manufacturer supplies the washer with the filter, if they do then yes you receive the washer, but some do not.
Is the rubber O-ring supplied with an oil filter?
Yes, if one is required.
Is the rubber O-ring supplied with an oil filter?
Yes, if one is required.
How long will it take for my order to arrive?
It will depend on the Delivery Service you select and where you live, please follow this link for the services you can select.
Which Courier do you use?
The vast majority of orders sent to UK destinations are sent via FedEx. We may use other couriers to UK outlying areas and islands. Overseas destinations are served by a variety of couriers but in the main we use FedEx. We currently send via FedEx to all destinations in western Europe.
What is your Returns Policy?
Please use this link to take you to our Returns Page.
How can I return items that I have ordered in error?
Please use this link to take you to our Returns Page, where the process is explained.
How do I order an item I missed from my order which I have already placed?
Please give us a call on 01209 215164, and we will add to your order and take payment as we do not keep your card details.
How do I get my Tracking No. for my order?
You should receive your parcel number via email. If you don't receive your parcel number, please contact us and we'll send it on to you. For orders sent via FedEx, you can track your order at http://www.fedexuk.net/accounts/track.aspx
I live outside the UK, can I have goods delivered to me?
Please use this link for the full list.