What synthetic oil do you use and why?

Discussion in 'Fuel Economy' started by regor, Nov 19, 2010.

  1. regor

    regor Active Member

    I’ve used synthetic (Mainly Mobil-1) oil since the 1980s. Never saw a MPG increase (And I keep detailed logs). I mainly use it for the added protection. I like to keep my vehicles for a long time.
    So I’m wondering if others have experienced the zero mpg increase with synthetic vs. conventional oils.
    Also, what oils do you use? Castrol has Syntec and Edge. Is Edge worth the added cost?
  2. ALS

    ALS Super Moderator Staff Member

    I run Mobil One 10W30 in my Volvo 960. Since it only gets one oil change a year it makes sense to use synthetic. Toyota fills the Prius with their own 0W20 synthetic. From oil analyses I have seen this new Toyota 0W20 synthetic is a very high quality oil. Toyota recommends a 10K or one year oil change interval with this new oil.
  3. seftonm

    seftonm Veteran Staff Member

    Used to use Esso XD-3 0w-40 for my 2001 TDI. Full synthetic, relatively cheap, and a pretty high quality product. Was very happy with it. For my new car, Mobil 1 ESP 5w-30. One of the few oils available in North America that meets VW 507.00 spec. Have always used synthetic to keep the engine happy and run the recommended 10k mile oil change interval.

  4. GaryG

    GaryG Well-Known Member

    I use what Ford says to use which is approved 5W-20. Mobil 1 has an approved 5W-20 synthetic but I've never seen any better MPG than Motorcraft 5W-20 Blend using Mobil 1. I've never seen a drop in MPG throughout the 10,000 mile oil change requirement in the FEH and it doesn't improve after a change.

    I have seen a ~1 1/2 MPG improvement using regular Pennzoil 5W-20 from using Motorcraft 5W-20 Blend, but the increase slowly drops at around 3,000 miles. I haven't tried Pennzoil in my FEH's because I go 10,000 miles between changes as recommended.

  5. nidly

    nidly Well-Known Member

    I use Amsoil (for the price) and have never seen any difference in FE on any different oil. I suppose I just got tired of changing oil so now I'm up to 2 year intervals in all my vehicles. I do a fleet of 20 or so trucks/cars and we've done 1 year intervals for 30+ years. The first 10-15 years was mobil 1 and the last 10-15 years was amsoil.
  6. Chuck

    Chuck just the messenger

    I've used Mobil One since the mid 70's.

    My Dad did not think it was worth it - Honda dealerships have discourage me, saying it gums up stuff.

    Back in 92, I credit it for keeping a catastrophic oil pan rupture from ruining the 1988 CRX HF's engine.

    I just change oil after about a year and 20,000 miles on my Insight. :)
  7. warthog1984

    warthog1984 Well-Known Member

    Mobil 1 5W-20. At first for better MPG (no luck), then just to keep the car in top shape.

    I tried 0W-20, but found that to be too thin for the Civic.

    Now I run it because I'm sure it saved the engine from heat-seize after radiator problems at least twice during racing season last year.

    3 changes in 3,000 miles, but its cheaper than an engine.
  8. Chuck

    Chuck just the messenger

    A good question is how often to change oil?

    I generally do it every 3000-4000 miles....20,000 is the exception.

    My leanings is sustainability of the engine is more important than more frequent oil changes that go into the recycle tank anyway.
  9. Neddy Seagoon

    Neddy Seagoon Active Member

    Castrol Syntec 5w-30 for my wife's 03 Cooper S, this is a once a year oil change which is way under the 25,000 kms that they recommend.
    Mobil 1 5w-20 for my 09 Vibe 2.4 which is usually twice a year due to mileage. And finally Kawasaki 10w-40 Syn in my 00 W650, again once a year change before I put it away for the winter, I have had no problems with the wet clutch on the bike due to using Syn oil.

  10. some_other_dave

    some_other_dave Well-Known Member

    I try to change my oil every 5,000 miles nowadays. That's up from the 3K I used to run. But I am a lazy sod sometimes, so I think it's been a bit more than 5K miles for this change.

  11. phoebeisis

    phoebeisis Well-Known Member

    I use Mobil 1 5w30 extended service in the Prius, but Mobil 1 10w30 in the 98 Suburban.

    I initially used 5w30 in the Suburban, but the warmed up-idle-oil pressure was 20 psi(I think GM claims as low at 8 psi is OK), so I switched to 10w30(vehicle has 215,000 miles).
    I can't measure any MPG difference between the 5w30 and the 10w30. Of course once warm the viscosity is about the same- so no surprise.
    It does get 20-21 mpg on long hy trips-cc set to 68 mph but lots of road work, towns cities where speed limit drops-average speed probably 63 mph..
  12. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Mobil 1 5w20. My Civic calls for 5w30, the van calls for 5w20. I like to only stock a single weight, and it (probably, but not measurably) saves a little gas.

    10,000 mile oil changes, when both manuals call for 7500. I may reduce that to 5000 on the civic, since it's in "severe duty" most of the time. Cold starts, long warmup, high load driving when it is on, mostly short trips, dusty/sandy environment. The oil was quite black this last time.
  13. alvaro84

    alvaro84 Homura-chan's selfishness

    We use Castrol ActEvo 10W40 in both bikes. It's semi synthetic though - does using fully synthetic help? (Help with with?, I could ask)
    We keep factory oil change intervals, 5000km for Ciliegia and 10000km for Teresa (~3k and 6k miles, respectively). The smaller engine contains a bit less oil and revs more on the highway, but Ciliegia is steadily shifting towards a joy bike role - it's mostly Teresa who gets the hard work (bad weather, 2-up rides and motorways). She's on a break now, though...
  14. LeanBurn

    LeanBurn Well-Known Member

    I use Pennzoil Platinum...it was on sale for less than half of everyone else and gets great UOA numbers. I use synthetic oil because the winters here can go from +15 to -40C and cold start protection is important.
  15. Harold

    Harold Well-Known Member

    Pennzoil Platinum as well. It is available in town in 0-20. Change ones a year. 06 Prius and HCH2 get it.:D H
  16. jcp123

    jcp123 Caliente!

    I wish I could use synthetic in the Echo, but it's got too many miles to start now. The Mustang could use synthetic if I used the right brand such as Redline which has sufficient ZDDP for my flat tapper lifters.

    I have never noticed a measurable increase in MPG with synthetic in anything save for my other Mustang which picked up about 1mpg, and that I am certain is attributable to going with a thinner viscosity when I switched...
  17. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    I started with synthetic in my Civic after it had conventional for 160,000 miles and 12 years. It still doesn't leak a drop of oil now at 182,000.
  18. jcp123

    jcp123 Caliente!

    I don't know...203.000 miles + poor maintenance makes me pretty hesitant to start...
  19. warthog1984

    warthog1984 Well-Known Member

    Go for it. Worst case, it starts dripping a bit, you replace the syn oil with mineral oil at the next change, and life goes on.
  20. jcp123

    jcp123 Caliente!

    Usually that'll start a leak which won't stop...

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