Motor oils for older cars

[IndyJimW]

For older cars use a name brand 5W30, a good oil filter and change it every 3,000 miles or once a year after winter. I believe it to be that simple.

I own a company that is a Shell distributor and has changed oil for fleets for over 25 years. I have used custom oils, taken tens of thousands of oil analysis, run extended oil changes on engines and have taken care of thousands of vehicles from the first oil change to the last. I have attended conferences by the oil companies about the newer oils and almost all the changes have been because of pollution controls and mileage standards. Some of the older additives don’t play well with catalytic convertors on cars or newer diesel trucks.

When I started as a mechanic the AVERAGE car engine needed a valve job by 40,000 miles and the engine rebuilt by 80,000 miles. A car with over 100,000 miles was rare. I would think that any modern name brand oil would make the engine last longer than it was originally designed.

Most of the discussion about flat tappet cams that I have seen is for high performance engines that would have more stress then older engine designs. For these engines I can see using a custom oil or additive.

Today’s motor oils are greatly superior to the engine oils of the 1960’s and any loss of additives would be made up for by their superior capabilities. I don’t like the idea of using 15W40 motor oil because most of the wear in an engine comes during cold starts. A 5W30 will crank with less resistance and build up oil pressure faster in Winter weather. Most of you probably drive less than 3,000 miles a year in your older car, I would recommend that you change your oil at the beginning of Spring so as to remove all the contaminates that cold Winter starts put into your crankcase. I believe that this is harder on your older engine then lack of additives in modern oil.

I’m not a big believer in motor oil additives, they change the base oil and no oil manufacture will warranty their oil if you add anything to it. I service thousands of gasoline vehicles that have over 150,000 miles on them using nothing but 5W30 or 5W20 motor oil.

Synthetic motor oil is the BEST oil you can buy, but I don’t think you need it. If I can get 200,000 miles out of a gasoline engine with regular motor oil why spend the extra money. I recommend synthetic if it was the OEM fill or in a high temperature environment, remember the Mobil 1 oil frying in the pan, or for cold environments. I have diesel trucks that sit outside all Winter and can’t be plugged in, they crank slow and are hard to start with a 15W40 diesel oil but change over to synthetic 5W30 diesel oil and they crank like its 70 degrees outside.

I hope that my experience can help this discussion.

Jim Wood

[IndyJimW]

I stand corrected; sometimes I go into stupid mode and don’t see the oblivious. I’m a Shell distributor so yesterday I called my supplier and asked for the Technical Engineers phone number. He told me the following:

Shell recommends Rotella T in ALL older cars. Rotella T 15W40 is good down to 0 degrees, for colder temperatures you can use Rotella T 10W30 or Rotella T SB 5W40. Rotella T SB is a synthetic blend and all current Rotella T formulas have 1200 ppm of zinc. If your car sits much you should change oil every 6 months because the oil attracts moisture and will form acids.

Jim Wood

[Twnchgr]

I stand corrected; sometimes I go into stupid mode and don’t see the oblivious. I’m a Shell distributor so yesterday I called my supplier and asked for the Technical Engineers phone number. He told me the following:

Shell recommends Rotella T in ALL older cars. Rotella T 15W40 is good down to 0 degrees, for colder temperatures you can use Rotella T 10W30 or Rotella T SB 5W40. Rotella T SB is a synthetic blend and all current Rotella T formulas have 1200 ppm of zinc. If your car sits much you should change oil every 6 months because the oil attracts moisture and will form acids.

Jim Wood

Thanks for taking the time to pass on the Information. Twn