Hidden Additives in Oils?

[vxcalais]

In Australia its common for the thicker oils and 20W50s to be used to quieten things down, at start up for the first 3 seconds yeah maybe some rattle, but cars have gone for years and years like this. I don't think the rest of the world is too different. Fair enough if you in extreme cold, or extreme heat, then sometimes other mechanical devices are used as well.

 

[Tempest]

I've always wondered if RP uses chlorine in their formulations based on the "spinning wheel" test results they get. There is way more than just an AW package to get their results.

 

[buster]

Originally Posted By: Tempest
There is way more than just an AW package to get their results.


No doubt about it.

 

[OMCWankel]

I have to side with FrankN4 in this debate. I used to use Mobil 1 15W50 in all my engines. I have lately tried lower VIS oils in the 5W20 to 10W30 ranges, Mobil 1, Pennzoil, and RLI. The UOA tests consistantly show higher wear numbers on the lower VIS oils in my vehicles used in Texas and Florida. This may just be a reflection of the formulation of M1 14W50 instead of a trend towards high VIS oils, or a reflection of the high ambient temperatures in my area, but at this point the results are on the side of M1 15W50.

 

[Tempest]

How much higher?

 

[OMCWankel]

Hi Tempest,

Higher iron and lead mainly, 10-20ppm with 5W30 VS 5 ppm or less with 15W50 $ 5W40. This is consistant regardless of the oil brand (RLI, Shell and Mobil tried). 5W30 is specified for the Miata in the owners manual. The Miata runs hot in the Florida heat, so I believe this heat is responsible for the increased iron and lead with the 5W30.

 

[brian12]

My guess is its the lowered zinc and phos in the lower visc oils that is causing the wear. Mobil 15w-50 has more zinc and phos than their other oils(except their moto oils and racing). Leave it to the gov to reduce the amount of additives to lengthen the life of a $150 part at the expense of an engine that costs thousands. I don't buy into the SM [censored].