1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Another benefit of Synthetic Oil

Discussion in 'Gen 2 Prius Main Forum' started by morpheusx, May 5, 2008.

  1. morpheusx

    morpheusx Professor Chaos

    Joined:
    Mar 6, 2007
    1,555
    81
    0
    Location:
    Akron, OH
    Vehicle:
    2011 Prius
    Model:
    Three
    I finally got around to mowing the grass this weekend. The grass had gotten a tad on the thick side as I have been too busy (lazy) to cut it. As I do every year I changed the oil to start the season with fresh oil. My mower just calls for 20 ounces of SAE 30 oil, so I decided to just dump in some left over 5w30 Castrol Syntec from my last oil change,. I have never used synthetic oil in a mower before because it just seems unnecessary. Anyway my yard is approximately 1/2 acre lot and the mower typically runs out of fuel as I'm finishing the yard and I have to add just a bit of gas to finish up. Today I finished the entire yard with out having to fill up and out of my curiosity I opened up the gas cap and looked inside, amazingly to my surprise there appears to be at least a quarter to half tank of gas left in the tank. I wasn't expecting any benefit at all so I was surprised.
     
  2. Sufferin' Prius Envy

    Sufferin' Prius Envy Platinum Member

    Joined:
    Jul 7, 2004
    3,998
    17
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    And just imagine how many extra feet a Hummer would drive if you add synthetic oil. :pound:
     
  3. Prius 07

    Prius 07 Member

    Joined:
    Jun 6, 2007
    715
    20
    0
    Location:
    Toronto, Canada
    Vehicle:
    2007 Prius
    Small World - I did the same thing (even the same brand and type) with my lawnmower (first time) last weekend.
     
  4. Prius 07

    Prius 07 Member

    Joined:
    Jun 6, 2007
    715
    20
    0
    Location:
    Toronto, Canada
    Vehicle:
    2007 Prius
    duplicate -sorry
     
  5. bbald123

    bbald123 Thermodynamics Law Enforcement

    Joined:
    Nov 13, 2007
    386
    271
    0
    Location:
    Harrisburg, PA
    Vehicle:
    2016 Prius
    Model:
    Four
    I've had mowers that specifically warned against multi-viscosity oils of any kind.

    You might want to check your manual.
     
  6. jayman

    jayman Senior Member

    Joined:
    Oct 21, 2004
    13,439
    639
    0
    Location:
    Winnipeg Manitoba
    Vehicle:
    2004 Prius
    Most air cooled motors do recommend against multi-vis oils, unless very cold. A typical generator, water pump, lawnmower, etc will spec SAE 30

    Most small Honda motors "allow" SAE 30 but prefer 10W-30. I guess you go with what works best. If there was no smoky exhaust, keep using it
     
  7. dogfriend

    dogfriend Human - Animal Hybrid

    Joined:
    Feb 26, 2007
    7,512
    1,185
    0
    Location:
    Carmichael, CA
    Vehicle:
    2007 Prius
    I wonder if this is because they are concerned about the effects of the Viscosity Improvers (polymers) added to create multi visocity oil out of plain old dino base oil? If so, it seems like synthetics would not have the same issue since they have little or no viscosity improvers.

    I just gave away my lawn mower with a B&S engine and they recommend SAE 30 unless operating below 40°F. No one in California would be mowing their lawn when it was below 40°. :pound:
     
  8. animalcontrol

    animalcontrol If my mouth moves, ignore me!

    Joined:
    Jan 7, 2008
    68
    0
    3
    Location:
    Greenwood, IN
    Vehicle:
    2008 Prius
    You must have a small yard....or are very lucky.

    Most (I'm giving the benefit of the doubt here) small 4 cycle motors REQUIRE a heavier oil, like 30W. Hence, 5W-30 is too thin and won't protect your motor.

    It would appear that synthetic is better than dino oil in this case also...I also tried this experiment in my younger days...replaced 30W oil with dino 10W-30. BOOM! Mower didn't finish the yard 1 time!

    Check your manual...you might need to drain and refill.
     
  9. Winston

    Winston Member

    Joined:
    May 19, 2007
    614
    20
    0
    Location:
    SF Bay Area, California
    Vehicle:
    2007 Prius
    There is no reason that the motor would be harmed with a 10W-30 or a 5W-30 oil. Multigrade oils are not thinner that an SAE 30 oil.

    Briggs and Stratton motors will run for hours without ANY oil in them. B&S did a test to show that because so many oil additive companies would treat the B&S engine, then drain the oil and say "See our additive is so good the engine does not need oil anymore!" It was not the additive that allowed the engine to run for hours, it was the durability of the engine.
     
  10. problemchild

    problemchild New Member

    Joined:
    Mar 17, 2008
    429
    36
    0
    Vehicle:
    2008 Prius


    HORRIBLE IDEA-------------WARNING!
    You will damage the engine mixing syn and non-syn oils. I did that by accident and had to rebuild my motorcycle engine when it messed up the cylinder and rings.
     
  11. lenjack

    lenjack Active Member

    Joined:
    Dec 1, 2006
    804
    114
    0
    Location:
    Pennsylvania USA
    Vehicle:
    2010 Prius
    Model:
    III
    Been using synthetic in 3 mowers over the last few years wih no problems.
     
    knettle3 likes this.
  12. OrlandoGuy

    OrlandoGuy Junior Member

    Joined:
    May 4, 2008
    98
    3
    0
    Location:
    Orlando, FL
    Vehicle:
    2012 Prius
    Model:
    Five
    I have a generator with a B&S engine that does recommend both a multi grade oil - 5W-30 and using synthetic oil saying that using synthetic will help prevent oil loss during running.
     
    knettle3 likes this.
  13. xsmatt81

    xsmatt81 non-AARP Member

    Joined:
    Mar 27, 2008
    522
    8
    0
    Location:
    Vegas
    Vehicle:
    2007 Prius
    very cool.

    I have an electric mower, for our 34x46 ft patch of grass heh
     
  14. jayman

    jayman Senior Member

    Joined:
    Oct 21, 2004
    13,439
    639
    0
    Location:
    Winnipeg Manitoba
    Vehicle:
    2004 Prius
    I think a lot of the older engines were pretty ancient with respect to what they believed to be oil quality. Modern small motors, especially Honda (Lawn mower, generator, etc) specifically state to use a 10W-30, not a straight 30

    Toyota is guilty of this too. My FJ has some odd requirements for gear oil. Front axle is 75W-90, GL-5 (A current spec). Transfer case is 75W-90, GL-3, a spec that has been obsolete for almost 25 years. GL-5 works for this spec

    The rear axle is the puzzler. Toyota states to use a straight SAE 90 gear oil, unless below 0 F in which case an 80W-90 may be used. Well, first of all, where outside of the Mid East, India, Mexico, Australia, or desert African countries can one readily find a straight SAE 90 gear oil?

    I hope Toyota doesn't factory fill the FJ with SAE 90. It turns solid as a brick below +5 F. I drained and refilled with Mobil Delvac Synthetic 75W-90

    Second of all, even with an 80W-90, that is unsuitable below -18 F. Again, some odd specs out there
     
  15. dogfriend

    dogfriend Human - Animal Hybrid

    Joined:
    Feb 26, 2007
    7,512
    1,185
    0
    Location:
    Carmichael, CA
    Vehicle:
    2007 Prius
    I used to work for a Class 8 truck manufacturer (name starts with a P) back in the 80's. I was on a visit to a dealer in Prince George, BC and they complained to me that the rear axle lube put in at the factory was completely unsuitable for their conditions. The first thing they did during PDI was to drain the axles and replace the lube with something that wouldn't turn into a solid at -20.

    Back to the Topic - I found this:

    http://www.briggsandstratton.com/maint_repair/parts_supplies/details.aspx?pid=100074


    [​IMG]
     

    Attached Files:

  16. jayman

    jayman Senior Member

    Joined:
    Oct 21, 2004
    13,439
    639
    0
    Location:
    Winnipeg Manitoba
    Vehicle:
    2004 Prius
    Yep, at one time Dana, Rockwell, etc used to spec either a straight 90, or something like an 85W-140. Now pretty much every HD axle is factory filled with a synthetic 75W-90

    Interesting about B&S motors. I guess they've come a long way from those ancient valve-in-head things
     
  17. Earthling

    Earthling New Member

    Joined:
    Dec 8, 2006
    441
    11
    0
    Location:
    Somewhere, NY
    Vehicle:
    2007 Prius
    I don't know what kind of bike you have, but my BMW motorcycle owner's manual allows full synthetic or dino oil, as long as the viscosity is appropriate for conditions.

    I've run dino oil and full synthetic, switching back and forth and have never seen any problem. Read the label on Mobil 1, and it will tell you it's compatible with conventional motor oil.

    I also have run Mobil 1 in my lawn mower, with a Briggs & Stratton engine. While that may seem like overkill to some, the motor only holds 0.6 quarts, and it has no oil pump. To me, this type of motor needs synthetic oil more than any other engine. This lawn mower has lasted a very long time, with no signs of blue smoke.

    Harry

    PS: there might be an issue with wet-clutch motorcycles. My BMW bike has a dry clutch, so the gear oil stays separate from the motor oil.
     
  18. jayman

    jayman Senior Member

    Joined:
    Oct 21, 2004
    13,439
    639
    0
    Location:
    Winnipeg Manitoba
    Vehicle:
    2004 Prius
    I missed this the first time around. That was certainly true enough, especially in the early to mid 1970's when multigrade oil was *real* crap

    We had just moved to Utah and my dad always ran a diesel rated SAE 30 in the Galaxy in summer, a 20 with a bit of kerosene in winter. That motor lasted a very long time

    But if even Briggs and Stratton now recommend a multi-vis, they've improved their motors and the oils are also good enough now to run a 5W-30 or 10W-30
     
  19. jayman

    jayman Senior Member

    Joined:
    Oct 21, 2004
    13,439
    639
    0
    Location:
    Winnipeg Manitoba
    Vehicle:
    2004 Prius
    I don't know much about motorcycles, except that a lot of motorcycle oils have special additives for wet clutch use

    A lot of industrial and commerical heavy duty equipment uses wet clutch, wet brake, wet PTO clutch, etc. The oils are specially blended to prevent chatter/grabbing of the clutch, and to prevent clutch glazing
     
  20. racerbob

    racerbob Member

    Joined:
    Mar 16, 2008
    138
    6
    0
    Location:
    S Florida
    Vehicle:
    2008 Prius
    Mobil claims they do not use friction modifiers in their motorcycle oils. Makes sense, as they can cause the clutch to slip due to reduced friction.