Diesel oil

Discussion in 'Oil' started by btsom, Sep 22, 2009.

  1. btsom

    btsom Active Member

    Posted this to the oil helpful hints thread and have gotten no response, thought I'd try it here for greater visibility.

    Read through all 12 pages here. My shop manual for a 2008 Road King says if adding oil that is NOT Harley's super duper stuff, it should be diesel oil- I quote the service manual: "If it is necessary to add oil and Harley-Davidson oil is not available, use an oil certified for diesel engines. Acceptable diesel engine oil designations include: CF-4, CG-4 and CI-4." Then it goes into viscosities.

    I have read the labels on most of the engine oils discussed here and have found no diesel specs listed. I originally used Mobil 1 15-50 automotive oil and was quite happy until I found the diesel requirement. There is only one oil I could find that had both the diesel spec and the viscosity range needed. Automotive oils with 20-50 viscosity are easy enough to find, diesel oils with 20-40 viscosity are easy to find, but only the 15-50 oil I'm using now has the desired viscosity range AND the diesel spec.

    How important is that diesel spec? I'd go back to either Mobil 1 or Mobil V twin if the diesel spec is not important. Your recommendation of Spectro 6 speed for the tranny is quite convincing. I will give it a try.
  2. hogrotten

    hogrotten Junior Member

    I believe what they are saying is if you cannot find a motorcycle oil to use an oil that is designed for diesel engines as they are high detergent oils. Mobil makes a V-Twin synthetic wich is a very good oil and is highly recommended among alot of riders, that being said whatever oil you decide on should be specificly designed for use in motorcycles.:57:
  3. paulmack

    paulmack Active Member

    As Hogrotten says whatever oil you use make sure it's designed for motorcycles. The Mobil1 V-Twin synthetic is a very good oil and you can get it at Advance Auto quite readily.
  4. glider

    glider Veteran Member

    What you didn't see is where they say to change it at the earliest convenience. Why do you think they say that?

    The Harley "super duper stuff" is garbage made by Hugo Chavez and is a blend and not a true synthetic.
  5. jaceddie

    jaceddie Junior Member

    I understood that to mean in an emergency when you couldn't get anything else, use the diesel oil to get you home, then change it.
  6. btsom

    btsom Active Member

    Thanks for the point out of the old article, I remembered some of that from a while back but couldn't find it. Everyone is honest about what they are expressing is their opinion, and that is appreciated. I always hope for something solid and I guess that just doesn't exist. Oil has always been much like religion. I am now much more comfortable that I don't have to worry about the diesel spec as long as it is good oil.

    BUBBIE Well-Known Member

    SOMEONE with more knowedege is WELCOME to jump in here....

    I believe that ::::20/50 multi weight oils are the FEW oils ALLOWED to have all the ANTI WEAR and ADDITIVES needed in the oils we (AIR-COOLED) engines need... HENCE.... DIESEL approved oils for use in our air cooled motors is about as close engineered to what KEEPS our motors working well...AS SAID ABOVE too much detergent and should change back to the APPROVED oil soon.....

    The 20/50 and 10/30 or 40 oil is different as I BELIEVE only the 20/50 IS still allowed all the anti wear chems. keeping our bikes in good shape....EPA is always MESSING with what works good and REMEMBER OIL : if it makes your motor last longer there's something BAD in it and we MUST take it out....

    some place I read about the NEWER car motors designed especially for the EPA values in new allowed oils to keep the air - earth clean.... YET DON"T put the oil into your harley or older cars as it will not lube and cool as needed....

    I'M all for keeping the air and earth CLEAN and around for a while yet but the GOV-EPA go about it in a very ILL mannered way doing more harm than good....JUST my opinion

    another example of EPA gone wild...

    EATING for example: FOOD...... IF it taste good ,,,,, spit it out cause it isn't good for you...

  8. springer03

    springer03 Active Member

    Diesel is not Paraffin (hope that is spelled correctly) base. Paraffin will dissipate with heat. Diesel engines run hotter than gas engines. (jmo)
    Last edited: Sep 23, 2009

    NEWHD74FAN Experienced Member Retired Moderators

    As posted earlier, diesel engine oil may substitute temporarily until proper motorcycle oil is found...so says the owners manual. In fact I have used on occasion in a pinch DELO (Chevron oil anagram for Diesel Engine Oil) which are high compression, high torque/pressure engines -- which sounds pretty familiar to HD owners). :D
  10. gs34

    gs34 Junior Member

    Actually, just the opposite is true.
    Especially in the head/valve area, temperatures are much hotter in a gas engine than in a diesel.