Am I using the wrong oil??

[MowatGTI]

Hey, don't want to sound like a spoon, but can you do serious damage with using the wrong oil or by mixing oils?

I put the expensive Castrol Edge 5w-30 grade in a while back when i changed it.  It's got a small leak, so ive been topping it up with the same.  I'm skint now, so Ive just bought 5w-30 grade but its halfords own brand.

Will this work ok? What oils do you folks use?

Its a '94 GTI 16v.

Cheers

[Len]

By using the same grade you wont cause any damage.
It is best to stick to the same oil but using different oils is far better than letting you oil go down to low levels.

[MowatGTI]

Cheers for that.

What oil do you use?  Same grade as mine or different?

I was in ADSA and they do different grades a lot cheaper then Halfords. Does it really matter the grade that I use?

[Len]

I use Magnatec, have done ever since it first came out!

[MowatGTI]

Ta!

[Pete Taylor]

Obviously fully synthetic is the best but semi is a more affordable option, it just requires changing more regularly. Personally I use 5w fully synthetic at the moment for winter which is has a low viscosity. You'll find a thicker oil is recommended for older or high mileage cars as they presume the piston rings will not be in the best of condition and can lead to it slipping through them and burning oil. I had a compression test done which came back all OK so it's alright for me to use. Best to go for the thinnest that the engine can cope with. If it burns oil (and you find yourself having to top the oil up) then get some thicker stuff

[MowatGTI]

Excellent.

Thanks for that.

Wasn't really sure about all the numbers so thats great. thanks

[boneybradley]

I use a semi synthetic 10/40 and change it every 6000 miles.... dont really see the point of using a fully synthetic (going by what an oil rep told me a few years ago!)

[Moos3h]

Depends on your style of driving.

If you're thrashing your car, fully synthetic will offer better protection.

If you're doing city driving, lots of stop start and never getting the thing hot, fully synthetic will be best.

But if you're driving normally, on a mix of journeys, and change it regularly, semi-synth is fine.

The viscosity of 5w30 in my opinion is a touch too thin, i'd recommend 10w40 Magnetec (semi synth) which is perfectly good and changing regularly - there's no subsitute for keeping an engine clean inside for ensuring a long and healthy life!

Cheers,
James