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Synthetic vs Conventional engine oil????

Discussion in 'Truck & Equipment Repair' started by GreatWhiteNorth, Feb 15, 2009.

  1. GreatWhiteNorth

    GreatWhiteNorth Junior Member
    Messages: 25

    What is your opinion. Is there any benefit to using synthetic motor oil? Being that the oil is the life blood of your engine, I change mine religiously every 3 months or 5000kms. If you change the oil regularly, is there really any benefit from using synthetic. A buddy of mine says the synthetic allows him to go longer between changes without break down. I get this, but if there are any small particles circulating with that synthetic oil that the filter can't remove, are you not just doing more damage than good? So within the 3month / 5000km period is there still a benefit? I can change my oil 2 times for the same cost as my buddy's one synthetic change. Will I truely get better mileage on synthetic? Thanks for your input!tymusic
  2. Mike N

    Mike N Senior Member
    Messages: 148

    Imo if you change your oil & filter at regular intervals you'll be fine with a conventional oil. I myself do my own oil changes every 5000 miles and have no problem with regular oil.

    The car in my avatar runs the quarter mile in the low 10 second range and I run conventional oil in that as well.
  3. mayhem

    mayhem PlowSite.com Addict
    from Peru MA
    Messages: 1,016

    Agreed. If you don't mind changing your oil regularly stick with conventional. Synthetic will give you a boost in economy, but not enough to cover the additional cost...less than a half mpg in my Silverado.

    I do my oil every 10k and filter every 5k with synthetic.

    I think that if you don't need to extended length between changes then you get no useful benefit.
  4. theplowmeister

    theplowmeister 2000 Club Member
    from MA
    Messages: 2,617

    I run synthetic oil and change every year before plowing and when I'm done plowing. In my car I run 10K miles between changes.
  5. CityGuy

    CityGuy PlowSite Fanatic
    Messages: 17,220

    My mechanic told me that there is not enough improvment in a truck to justify the extra cost. A sports car is a different story. In my honest opinion I have no clue if one is better than another. I run regular as I can buy it cheaper in bulk at Costco.
  6. stroker79

    stroker79 2000 Club Member
    Messages: 2,802

    Well I switched to syn recently on my diesel pickup and I will never go back to conventional oil. My truck starts up MUCH easier in the winter which tells me that the oil flows better and creates less resistance in the engine which I would think is good.

    The oil is def not twice the cost and I can go twice the oil chang interval however instead, I will change at 8k-10k intervals instead of 6k intervals with regular oil.
  7. JDiepstra

    JDiepstra PlowSite.com Addict
    Messages: 1,780

    Synthetic is definately an improvement in many ways, as mentioned above... Also, I go 20,000 miles on my Amsoil or more and my oil analisys verifies that it is "fine".
  8. xtreem3d

    xtreem3d PlowSite.com Addict
    Messages: 1,548

    according to 2 buddies who are mechanics for UPS here in st. louis if you change your oil regularly there is NO benefit to synthetic. UPS uses syn in thier long haul trucks but the start and stop trucks get regular oil. also according to them UPS has done extensive research into when and why to use syn vs conventional oil....something unrelated that i found interesting an air filter for a car is not it's most effective until it is about 20% clogged/dirty.
    Last edited: Feb 16, 2009
  9. HinikerPrototyp

    HinikerPrototyp Member
    Messages: 88

    I have been running synthetic motor oil in my diesel since 2002, it cranks over so easy when its colder then crap outside.The first year i had it 2001 i used Rotella and it started so hard and shook like it was on one cylinder. I have about 79000 on the girl and usually change it once a year and it doesnt use any oil .You do have to check your air cleaner more often due to the salt dust clogging it all the time.
    Last edited: Feb 16, 2009
  10. 06Sierra

    06Sierra PlowSite.com Addict
    from Maine
    Messages: 1,329

    It cost me $15-$20 more for an oil change with synthetic over conventional oil. But I only went 3-4000 miles between changes on conventional and 6-7000 on synthetic. The main reason for changing over is the cold weather starts. Synthetic does much better when it's -40!
  11. justme-

    justme- 2000 Club Member
    Messages: 2,138

    To most people there is no benefit to syn if you change your oil regularly, and "regularly" needs to be defined as "soon enough".
    The determining factor in oil is the additives which get used up. Oil will still lubricate long after it is after to provide the additives needed to keep it from sludging, coking, gumming, etc.
    The lesser quality dino oil will use it's additives sooner in most cases, and the viscosity breakdown (where it stops lubricating) often happens sooner too.

    Synthetic oil is beneficial in high performance engines (sports cars, turbo charged engines) as well as working engines and cold weather engines. Synthetic is available in wider viscosity ranges the Dino oil, and usually extends to a thinner oil in it's cold state meaning cold starts get oil sooner, which is where 90% of the damage and wear is done to an engine (because there is little oil....). Synthetic always has higher viscosity breakdown numbers, and most synthetics can capture more soot than a dino oil so diesel engines can run longer on a change before it turns black.

    Been running Synthetic in my CTD since I got it and I have been told by Cummins mechanics (I'm near Cummins Northeast) they have seen Dodge diesel's running synthetic with over 250K miles still looking like new inside, not with the typical wear a conventional oil engine has. What does that say? Cummins/Dodge has 6K change intervals for dino oil... I run 6K in the winter because of plowing, and 7-9K the rest of the year between changes- and a new Fleetguard filter (never use fram) at each change.

    I have also seen first hand the benefits on a Unimog which gained a lot from switching to Mobil 1.
    Last edited: Feb 16, 2009
  12. augerandblade

    augerandblade PlowSite.com Addict
    Messages: 1,054

    tymusicWe use synthetic oil 0W40 in our 6.5 diesels cuz it gets COLD here and its hard to start when the oil is syrup. :nod: Only if your a worry wart would you have a concern that a oil filter is not doing the job. :nod: Its not the oil that breaks down (im told) but it is the additives that get depleted over time. Big fleets running highway test their oil at regular intervals if it comes back with a pass they just change the filter and dont change the oil.:nod: Please dont tell me different otherwise I'll become a "worry wart:
  13. creativedesigns

    creativedesigns PlowSite.com Addict
    Messages: 1,929

    I've never heard such nonsense before! :dizzy: Conventional or Synthetic oil does not alter the oil change intervals in any way. In fact a lot of PS guys who run diesel engines play russian roulette with them. Every 3 months or 5000k is what a diesel technitian should tell' ya. Everyday we must check the oil levels in all our trucks before starting them...it's so essential for the life of the engine.
  14. Danhoe

    Danhoe Senior Member
    Messages: 102

    My 1995 K 3500, 6.5 L. diesel has 247,500 miles on it been running Amsoil in it, the truck scales out at 13,000 lbs when I put amsoil in it I could see a temp. drop and starting easier in the winter. I now run it in my pumps, cut off saws and my Linkbelt excavator, next I will be putting in in my Cat backhoe. I also run it my wife's car. I am happy with it. Don't hesitate to run it. I put on at least 125 miles a day on my K 3500, it doesn't miss a lick. Dan
  15. MileHigh

    MileHigh PlowSite.com Addict
    Messages: 1,827

    Synthetic Oil Only...It's what my trucks deserve.

    Plus it's the filter that needs changed before the oil.

    Rotella Syn 5w40 in the diesel.
    Mobil 1 Extended Performance 10w30 in all gas engines.

    Anyone who tells you Dino oil will run just as good and provide similar protection as Synthetic oil is a crackhead.
  16. Mike N

    Mike N Senior Member
    Messages: 148

    Seems most of the people chiming in here for synthetic run a diesel- Maybe there is a benefit for them but for a regular gas engine dino oil is plenty good enough for me.

    Years ago I was a crew member of a 7 second 190+mph Corvette that we ran in NSCA's outlaw street category. We ran a mix of 20w50 and straight 30 Napa conventional oil. Nothing trick here, regular wet sump 7 quart system with an ordinary AC delco filter. This thing produced 1000+ horses on engine alone, and near 1500 with the nitrous turned on. At the end of the year we tore the engine down to inspect it, and the bearings still looked like new. So good, in fact, we cleaned them and used them again the next season. In all the years I've raced my own car and/or crewed on a faster car we never nicked a bearing, or had any oil related failure. We may have wadded up a few pistons from an over agressive nitrous tuneup, but nothing you could blame on the oil we ran.
  17. stroker79

    stroker79 2000 Club Member
    Messages: 2,802


    Yes oil level is very important on our trucks but I check the oil once a month if that. Over the period or 8k miles i might use a quart of oil and thats partially because I have a small oil leak. I have Oil Analysis done every other OC at about 5k and the oil is always in great shape and they say that I am ok to run another 3-5k more on that change.

    Also if you need anymore detailed reports and testamonies, head over to ford-trucks.com and start reading.
  18. BigDave12768

    BigDave12768 PlowSite.com Addict
    Messages: 1,446

    Gota agree with all the posts. its better to start a diesel with in cold weather. They fire up much easier and quieter. I also saw a small mileage increase. For a regular gas engine in a pick up. It would work well if you keep you trucks along and into high mileage.
  19. theguynextdoor

    theguynextdoor Senior Member
    Messages: 308

    Is it true that if you have always ran conventional in a truck/car with a lot of miles on it that switching to synthetic is not good? I tried to switch to synthetic in my 1998 Dodge 2500 with 130,000 miles. It burned that synthetic twice as fast as conventional. I suppose this might not be the case in all trucks because mine burns oil and coolant...and ALOT of gas. If i bought a new car/truck I would immediately switch it over to synthetic when I bought it.
  20. GreatWhiteNorth

    GreatWhiteNorth Junior Member
    Messages: 25

    I tried synthetic in my 97 silverado. I had always run conventional oil and changed it religiously. As I drove out of the Lube place we use with my $70.00 synthetic oil change, the truck started ticking (lifters I was told later). My mechanic buddy said that the synthetic was so good at what it does that it removed the varnish from the lifters and exposed the slight scars causing them not to pump up as efficiently thus causing the ticking. The truck had 200 000 kms at the time and had never ticked in its life. My mechanic suggested running the synthetic only for a short time to clean up the rest of the engine and then dump it and go back to conventional. I did just that. It took awhile (and some oil additive) but the lifters eventually stopped ticking. I asked my mechanic about our new truck and he said as long as we stick with the synthetic from new, chances are that we will get longer life out of the engine. He said I was not the only one that he had heard of having problems in an older engine with synthetic. I am still waiting to hear what everyone else has to say about synthetic. Thanks to everyone for their input!