Why Synthetic Is Better Than Conventional Oil

Discussion in 'Dodge Challenger General Maintenance' started by SRT-Tom, Oct 13, 2022.

  1. Moparisto

    Moparisto Full Access Member

    Posts:
    1,159
    Likes Received:
    201
    Joined:
    Jun 11, 2022
    Location:
    White Sands
    Oh, okay.

    Never thought of just mixing up some oils in an alchemical fashion. :D

    But, in its trip through the engine, the hottest the oil is going to get is when it cools the piston domes from the underside. Also hot will be oil in contact with the exhaust valve stem and roof of exhaust port. Obviously, the film of oil facing the combustion chamber on the cylinders will be hot.

    I wonder which oil location in the engine would most directly benefit the lubricating properties by being aggressively cooled. The oil film in the plain bearing must get rather toasty, if only momentarily, due to the pressure and friction, such as on the cam bearing, and the crank bearings as they do face some high loading in addition to the highest RPM of any part in the engine (other than the oil pump?)

    Oiling is not a really heavily-parsed system even as of yet. The "state of the art" thus far is just throw a dry sump and a thermostatic cooler on it and call'er done. The problem being, of course, with dry sumps, is that all those additional scavenger sections that suck up the oil spray and evacuate the air from the crankcase consume power that is not returned to the engine during normal usage. If I recall correctly the F1 engines are mandated to have a dry sump system, last rule set I read through. At 15,000 RPM, that makes even more sense, though I'm not sure they have higher parts linear speeds in and F1 engine due to the super-short strokes.

    If one could super-cool the oil just moments before it hit the most heat-stressed portions of its travels, one could save some energy from being needlessly wasted.

    BTW, oil spray cooling the valve springs can help with their longevity to reduce from the heat they generate due to the springing action costing some internal heating due to hysteresis.

    Titanium springs are very low-hysteresis and low weight, but oy, they just don't have anywhere near the longevity of the good ol' spring steel. Great if you are drag racing and have a huge budget. Not so great if you don't.

    By cooling the oil, you can reduce its peak temperatures to better suit its purposes. As with many things, just adding massive oil cooler capacity can really assist, keeping your oil from hitting peaks that are too high.

    Also, as one user pointed out above, just changing it more often to avoid breakdown of its best properties.

    Also, why not use a catch can to keep the stank oil out of one's intake system?
     
  2. fritzthecat

    fritzthecat Full Access Member

    Posts:
    364
    Likes Received:
    174
    Joined:
    Aug 15, 2019
    Location:
    Sunny Boca Raton
    Does that really work? If I mix say, 5w30 and 5w40 half-and-half do I get 5w35?
     
  3. stingray

    stingray Full Access Member

    Posts:
    854
    Likes Received:
    173
    Joined:
    Feb 26, 2012
    Location:
    California
    upload_2025-4-26_11-34-10.jpeg
     
  4. SRT-Tom

    SRT-Tom Well-Known Member Staff Member Super Moderator Article Writer

    Posts:
    7,698
    Likes Received:
    2,603
    Joined:
    Oct 2, 2011
    Location:
    southern New Jersey

    Here is advice from three oil companies:

    From the Chevron.com site: "Can I mix different viscosity grades of motor oils?" "Yes. It is always advisable to not mix motor oil brands, however, different viscosity grades of the same brand motor oil are compatible. Be aware that mixing viscosity grades will turn out a product that is different in viscosity than either what was originally in the engine or what was added."

    From Shell.ca: "If you mix viscosity grades such as a 5W30 low-viscosity oil and a 10W40 higher-viscosity oil, it is reasonable to expect that the resulting product will have viscosity characteristics which are thicker than the 5W30, but thinner than the 10W40. This change does not reflect incompatibility - it's simply a re-balancing of the viscosity characteristics. In all other ways, the product should work as expected. But there's absolutely no danger about incompatibility resulting from mixing engine oils," Miller says. "We've tested all of our grades and brands, and we haven't observed any problems."

    From Mobil1.com: "For our customers to choose a viscosity grade, we recommend they follow the engine manufacturer's recommendations as indicated in their owner's manual. There is no need to mix two Mobil 1 viscosity grades when one will do; however, we see no problem mixing different SAE grades of Mobil 1 Tri-Synthetic series motor oils."
     
  5. Sexy Blue

    Sexy Blue AKA Bob

    Posts:
    626
    Likes Received:
    196
    Joined:
    May 31, 2024
    Location:
    Hudson Valley, NY
    Was an Amsoil guy>Mobli 1 guy>Pennzoil guy...

    I grenaded a 2010 Sprinter, using the correct Pentosin oil in it, spun a bearing less than a mile from home. So much for Mercedes über engineering.
     
  6. stingray

    stingray Full Access Member

    Posts:
    854
    Likes Received:
    173
    Joined:
    Feb 26, 2012
    Location:
    California
    Which Mobil 1 viscosity 5W-30?
     
  7. stingray

    stingray Full Access Member

    Posts:
    854
    Likes Received:
    173
    Joined:
    Feb 26, 2012
    Location:
    California
    There is also I have heard of Valvoline Restore & Protect but I am not sure if that is what you would need or if it helps if you have carbon deposits.