Affects of using wrong engine oil?

[zanwan]

Hi all

What are the possible consequences of using the wrong type of engine oil?

I currently have a 1995 ford escort petrol. I am supposed to use 10w40, however my car is burning oil and therefore i'm having to refill regularly, so was wondering if i could get away with using Asda value 20w/50, which is £6 for 5 litres?

What could be the possible impact on the car if any?

 

[Diyisfun]

Have a read here
http://www.carbibles.com/engineoil_bible.html

 

[nickso]

on an escort driven normally there will be little effect.

oil grades have more of an effect on cars driven hard or used in extreme conditions. 20w 50 might be a bit harsh for the engine in the winter though.

 

[Burnerman]

If your Escort has the Zetec 16v engine you risk valve sticking problems if you don't use the specific oil....however if the engine has many miles on it you could try a 15/40 grade - but it will have little effect on the oil burning issues.
John

 

[Mickymoody]

Ford engines of that era are renowned for being stood, the oil solidifying in the sump, and causing massive engine problems.

Can only suggest running an oil treatment through the engine, or a strip down and valve stem oil seals replacing. '95 Escorts were poo. My 95 car runs 0w30, no oil leaks. Celica.

 

[pompeyal]

If your engine has hydraulic tappets, using cheaper oils may effect them and make them noisy.

 

[Nige F]

Ford engines of that era are renowned for being stood, the oil solidifying in the sump, and causing massive engine problems.

Can only suggest running an oil treatment through the engine, or a strip down and valve stem oil seals replacing. '95 Escorts were poo. My 95 car runs 0w30, no oil leaks. Celica.

Agreed , but I know of one that the guy owner Never Changed the oil . After about 10 years - it needed an engine rebuild BUT he worked it out that it was Cheaper than all those oil changes @ a garage

 

[Avocet]

Have a look at the standard that the supermarket oil meets - it will be something like API "SJ" or "SF" some pair of letters. That's an indication of the quality of the oil. Check what's required in your owner's handbook. As long as it's of the right quality, I wouldn't be too bothered. As it's a higher viscosity, you might notice a slight increase in fuel consumption. Alfa engines drink oil like it's going out of fashion and they recently specified a fully synthetic 10W60 to combat oil consumption.

The bigger the gap between the two numbers, the harder the oil has to work. Presumably, if this is cheap supermarket oil, it's a mineral oil? IF so, it's unlikely to be 20W50 for long, as the long chain molecules break down. If you use the car hard or tow with it, I'd be inclined to spend a fair bit more money for a fully synthetic. You might even find that oil consumption is a bit lower anyway, just using a good synthetic of the right grade. IF it's a car that hasn't long to live anyway, I wouldn't worry.

 

[ericmark]

I remember the problems in mixing oil from years ago. Motor cycle ex-track had run all it's life on Castrol R and since rather expensive my mate decided to change to standard mineral oil. The engine would have run on either but not a mix. And this is the problem unless one type is completely cleared from system it can react with old oil and although not to extent of mixing mineral and vegetable oil it is still a problem as the amount of detergent if reduced will allow clogging of oil ways and if increase can loosen muck already there and move it to some where where it will block.
Only time to change oil type is after an engine re-build. Some engines do need special oils. Automatic mini for example could not have enhanced oils and additives or the bands and clutches in the gear box would slip. The Automatic box formed sump for engine. As already pointed out hydraulic tappets may need correct oil. The Buick engine fitted to Rovers had pure hydraulic tappets and correct oil was very important but the Vauxhall Royal have hydraulic tappets with manual adjustment and it was no where near as important. Variable valve timing also uses hydraulics and can also be effected.
So under normal use does not seem worth the risk in using wrong oil.