Mixing motor oils (for dummies)

Had a ‘top up oil level’ warning come on so whilst I was out popped to Halfords and the Tesco next door.

Halfords guide said 5w-40 which is fully synthetic, Castrol guide in Tesco said 10w-40, part synthetic, user manual for the car lists pretty much everything, last 2 service stamps don’t say and the 1 prior states 10w-40.

I went with 10w-40, but does it really matter what’s in there already? Any issues mixing fully/part synthetics if either separately would be fine? It was given a service before I bought it but clearly they didn’t check the oil.

It is a Renault Megane 56 plate 2.0 16v non-turbo petrol.

Anything better than the nothing you had in there!!!
And for a non turbo petrol it really won’t matter but you have chose a good all round oil so it will be fine

No all are capable of being mixed, can’t remember what the standard is that decrees that, but pretty much any oil available to buy over the counter will comply with it.

http://www.carbibles.com/engineoil_bible.html

http://ew5.earlweb.com/search.php?site=220&region=258&language=5&brand=1

Car wasnt serviced then

You cant service a car and not check the oil ( service involves changing the oil)

Ime with the exception of a few (usually reasonabl tuned and turbo) Engines using oil is a sign of exceedig service intervals or a leak(internal or external)

For the sake of 50 quid of oil and filters i would drop oil a change it. I don trus garages trying to sell me something to do what they say they will. Of course they may have just not filled it up right but it has to be pretty low to trigger the light !
Easy way to tell if it was serviced would be to pop open the air filter and look at it.

trail_rat – Member

Car wasnt serviced then

You cant service a car and not check the oil ( service involves changing the oil)

He doesn’t say when the last service was 😕

Serviced when he bought it he says . Not really worth mentioning unless this was recently , although you might be right given the general lack of mechanical sympathy the general car driving public give it was probably bought at 3 years old 🙂

Seriously though giving it a service is pretty much the first thing i do on any car i buy. Bitten once twice shy as they say … Bought. Car with a reciept for a timing belt change 5k/6 months before . Doubt it was changed as it shit its self 20 k later – 60 k interval.

Agreement on purchase was service, 12 month mot and 4 new tyres (sidewalls perished and on previous mot,) when I purchased it. Brought from a dealer, service etc done at local garage so I trusted them. Car has done 500 miles or so since I bought it. Only done 46k.

A constructive conversation will ensue on Tuesday. Can’t fathom a leak anywhere as the weeds on the drive have no sign of oil.

Hence my concern ste , oil doesnt just vanish , theres a reason for it.

Unkess chrisdiesel comes along and says these cars have a similar inherantly bad engine design to the 1.4 golf engine ….. It burnt oil. For fun.

Some dodgy deal between garage and dealer seems likely then.

I trust the mileage as the bloody thing costs a fortune to run, so will speak to the garage in the week. Will chuck enough oil to be safe for the time being.

Cheers

trailrat is saying take the car back and get them to sort. It would normally take at 1/2 litre of oil to trigger the oil light. 1/2 litre in 500 miles is very worrying. Have you checked the level on the dip stick as well as oil filler cap and coolant?