Results 1 to 7 of 7

Thread: Synthetic Myths

  
  1. #1
    Status
    Offline
    oilman's Avatar
    Discounting Trader
    Join Date
    Mar 2005
    Location
    Sunny Cornwall, UK
    Posts
    629
    Mentioned in
    5 Post(s)
    Quoted
    0 Post(s)
    Follow oilman On Twitter Add oilman on Facebook

    Synthetic Myths

    I read so much stuff on the internet about Synthetic Oils that is simply not true so I felt it was time to tell the truth rather than accept the myth.

    So in future when you see someone state any of these, please do me a favour and point them at this thread!

    Synthetic motor oils damage seals:

    Complete Nonsense! Any oil seals made after 1975 or thereabouts will be entirely compatible with any type of synthetic engine oil. (The same goes for synthetic gear oils and transmission oil seals.) It must be understood that everything associated with lubrication is thoroughly tested. The major oil manufacturers do not make oils that attack seals; seal manufacturers ensure that their products function correctly with modern lubricants.

    Synthetic oils are too thin:

    It is true that the best synthetic blends can be low viscosity (0w-20 for example), but they do not have to be! It is also true that the latest engines are designed to run on thin oil, which improves power output and fuel consumption. Even so, thicker synthetic based grades (10w-50, 15w-50, 20w-50etc) are available for air-cooled motors, older engines, or severe high temperature conditions. These grades can also benefit rebuilt classic engines dating back to the 1940s.

    Synthetics mean higher oil usage:

    The complete opposite of the truth. Oil consumption in well-maintained modern engines is mainly down to the oil evaporating at high temperatures. Synthetic base oils (specially the PAO and ester types) are very resistant to evaporation loss even in low viscosity blends, so oil consumption is minimised. Obviously, engines with worn valve guides, defective seals and worn piston rings will use oil regardless, so there is no point in using expensive synthetics as an ‘old banger lube’.

    Synthetic oils are not compatible with other oils:

    All engine oils intended for normal road use in recent 4-stroke engines are compatible with one another, regardless of the base make-up. (mineral, PAO/ester/hydrocracked synthetic, and semi-synthetic.) There is no need to flush or strip down an engine when changing from one type to another. (…but be careful with the exception: castor oil based racing oils.)

    Synthetic oils produce sludge:

    Well honestly, this is just totally daft. All synthetic bases are more resistant to oxidation than mineral oil, and sludge is largely due to oxidation. In any case, all motor oils intended for road use meet the higher API specs such as SH, SJ, SL and diesel equivalents. One of the main reasons for introducing the API specs back in the 1950s was to deal with oil sludge problems. All high-spec oils run very clean, especially synthetics.

    Synthetic oils cannot be used with catalytic converters:

    ‘Cats’ will perform more efficiently and last longer if synthetic based engine oil is used. Their lower volatility (see 3 above) means that less oil reaches the combustion chambers via crankcase ventilation, so there are less harmful ash residues from burnt oil to de-activate the catalyst matrix.

    Synthetic oils can void warranties:

    People who make statements such as this never define the type of synthetic, thus revealing their ignorance. Provided that an oil meets or exceeds the API and viscosity ranges specified in the handbook, the warranty will not be affected. (By law, OEMs cannot insist that a particular brand of oil must be used to maintain warranty.)

    Synthetic oils will last forever:

    The better synthetic blends will certainly last longer*, especially in high performance or high annual mileage situations, but ‘forever’ is not on, simply because contaminants such as soot, and acid gasses from traces of sulphur in the fuel degrade the oil.
    (*Provided that a very shear resistant VI improver polymer is used in the oil formulation to keep the viscosity up to spec. This point is often forgotten.

    Synthetic oils are too expensive:

    True, for older vehicles that use a lot of oil or are almost ready for the scrap yard. For cars that are worth maintaining, the right types of synthetic oil are a cost-effective way of retaining ‘as new’ performance, low fuel consumption, and reducing maintenance costs. (See 6 above, for example. ‘Cats’ aren’t cheap!)

    Cheers
    Simon
    Use the code ASTRAOC and get 10% Club Discount
    oilmans website : www.opieoils.co.uk/
    e-mail : oilman@opieoils.co.uk

  2. #2
    Status
    Offline
    dannysport18's Avatar
    AOC Obsessed
    Join Date
    Sep 2003
    Posts
    35,241
    Mentioned in
    7 Post(s)
    Quoted
    7 Post(s)
    Simon what oil would i be better off using
    http://www.m1gst.com/vb/showthread.php?t=50326

  3. #3
    Status
    Offline
    AndyGSi's Avatar
    AOC Fanatic
    Join Date
    Feb 2005
    Posts
    775
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    A good read there Si
    Astra GSi Turbo, SOLD


  4. #4
    Status
    Offline
    oilman's Avatar
    Discounting Trader
    Join Date
    Mar 2005
    Location
    Sunny Cornwall, UK
    Posts
    629
    Mentioned in
    5 Post(s)
    Quoted
    0 Post(s)
    Follow oilman On Twitter Add oilman on Facebook
    Quote Originally Posted by dannysport18
    Simon what oil would i be better off using
    http://www.m1gst.com/vb/showthread.php?t=50326
    For the best levels of protection 5w-40 synthetic.

    There are plenty in my December Oil Offer.

    Cheers
    Simon
    Use the code ASTRAOC and get 10% Club Discount
    oilmans website : www.opieoils.co.uk/
    e-mail : oilman@opieoils.co.uk

  5. #5
    Status
    Offline
    twiz46's Avatar
    AOC Regular
    Join Date
    Sep 2011
    Posts
    86
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)

    gearbox oil change

    Is it necessary to change manual gearbox oil at all, I thought manufacturers did away with oil drain bungs on boxes because it doesnt need changing.
    Also what does hydrocracked mean.
    and at what point does a an oil become a fully synthetic rather than a semi

  6. #6
    Status
    Offline
    nry's Avatar
    Cumbria RO | Club Team
    Join Date
    Mar 2008
    Posts
    25,986
    Mentioned in
    48 Post(s)
    Quoted
    1 Post(s)

  7. #7
    Status
    Offline
    oilman's Avatar
    Discounting Trader
    Join Date
    Mar 2005
    Location
    Sunny Cornwall, UK
    Posts
    629
    Mentioned in
    5 Post(s)
    Quoted
    0 Post(s)
    Follow oilman On Twitter Add oilman on Facebook
    This should help too.

    http://www.opieoils.co.uk/pdfs/tech-...scriptions.pdf

    Gear oils need changine, no matter what the manufacturer might say. All oil breaks down, and while gear oils may last longer than engine oil, they do not last forever. Manufacturers advise against changing gear oil for 2 reasons

    1) It keeps the costs of servicing down.
    2) The manufacturers don't want the car to last forever

    Cheers

    Tim
    Use the code ASTRAOC and get 10% Club Discount
    oilmans website : www.opieoils.co.uk/
    e-mail : oilman@opieoils.co.uk

Similar Threads

  1. Fully synthetic oil Vs. semi synthetic oil
    By d_ghedia in forum NA Engines (Non-turbo petrol) inc. Transmissions
    Replies: 3
    Last Post: 26-06-2007, 22:27
  2. Did You Know these are just myths?
    By A5TRA 59ORT in forum Chit Chat and a Warm Welcome!
    Replies: 10
    Last Post: 29-09-2004, 17:49

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •