wall

Posting here due to no answers on tech forum .... plese need expert help.

I no longer have my Sti (moved to a current model R32 golf) but I have a general tech question that I know you guys can help me with.

Yesterday I was out of town and checked the oil during a petrol stop ... to find out that it was very low! I therefore immediately decided to top il up, however I was in a relatively isolated place on a sunday, and the best I could get was some crappy semi-sinth old (pre-Helix) Shell plus, called Shell Sint Plus 10w-40.

So I added 1litre of that to the 5w-30 full-sint that my R32 uses, thus ending up with a tank which now has 4/5 5w-30 full-sint Total and 1/5 10w-40 semi-sint Shell.

Since getting home I've been worrying about it ... is it quite ok, with the new crappy oil simply mixing with the vast majority of good oil, or is it better to head to the dealership for a full oil change ($$$)...???

Stressed for my new "baby" well being ... thanks for the advice!!!

Wall

Shark Man

It depedns on how old the oil is that was already in the car, when its due for its next change and how much oil you needed to add to top it up.

It should mix ok. May even give the current old oil a bit of refresh due to the extra Vi improvers and detergents added, the viscosity is only one grade thicker so wouldn't that much of an issue imo.

generally speaking, half a litre or so of top-up oil wouldn't be a problem. Although if you had to top up by several litres, I'd consder doing a basic oil and filter change - especially if the old oil already in there for some time, and its a long way off before its next service interval.

However, special concern needs to be taken with regard to the vehicle's warranty. If its on the variable (longlife) service schedule, then it must use the approved VW longlife oil to remain under warranty. They will however allow a small quantity of non-approved oil for ermergency top-reason, and it will do no harm to the car, but owing to the technicailities in the warranty clauses, maybe an idea to change it if any sisgnificant amount of non-VW approved oil was used.

You wouldn't need to use a VW dealer to change it though, any competent garage can perform this task - just as long as a genuine filter is used as well as VW approved oil, the warranty will not be affected.

wall

Thanks so much for the advice, in the top-up I added 1liter of the "crappy" oil to the overall 5 liters of full sint that the car uses, so it's 20% of the total.

The car is very new (6000 miles) so the oil was very new, never changed yet, it does have the VW longlife warranty so I'm wondering if the 20% of semi-sint added is a problem and I better change it all, or if given that it is only 20% of the total, and that the rest was top-quality and very fresh, if will just mix in and be of no concern to the engine nor to VW.

Wall

Beastie

iTrader: (2)

Synthetic oil does not oxidise like mineral oil and that is why it does not need changing as often. It also does not produce as much carbon build up in the engine and is better for the engine. As has been said if you are on the service meter on the car instead of the annual service then you shoulc defintely use the VW approved oil. As far as i am concerned (I dont know for sure , but as a qualified engineer) the oil in use must be of the fully synthetic variety.
Having said that, as your engine will use another litre of oil in another 6000miles then i would check with VW and get a litre of the proper oil and dont worry about the litre of semi-synth. That is providing that the cheap oil you put in meets the requirements of VW. Check the carton against your owners manual.