Originally Posted By: Greasymechtech
Badbul, time schedule is fine for twice a year on both of fleet... March and September should keep you out of the snow or maybe April/October... Your engines, good full synthetic oils, oil consumption top-offs, oversized filters.... really will do plenty to lower your oil change interval from 3x a year to 2x a year.
Check to see if you have knock sensors on the fleet of engines. If so, there is enough timing to prevent the so-called over-hyped carbon buildup with premium fuel. Use premium for the summer months, midgrade for fall/spring, and regular during the winter. My Toyota's tend to be a little weak during summer months with the A/C on while using regular. Premium cures the issue every time. Regardless of which octane you chose, stick with
http://www.toptiergas.com/retailers.html
Both engines should be able to fit an oversized 3/4-16 filter, which provides plenty of media for longer intervals. I've used the PH3600/FL400s/51516 sized filter on multiple 4 and 6 cylinder Toyotas. It'll take about a cup more of oil at the oil change interval. No need for fancy overpriced synthetic media filters.
Oil top-offs for oil consumption will also refresh the oil and reduce the need for extra oil change intervals.
Save a little time and money by maintaining twice instead of 3 times per year. But, over maintenance has never hurt an engine. I don't care for the SAE paper argument, usually a good read or study but too many variables left out. If you don't mind wrenching, keep what you're doing. But, with a good synthetic, oil top offs,.... oil should be fine with 6 month interval instead of 4 month interval.
RoyalPurple, Pennzoil, Mobil1, Valvoline... have full synthetic high mileage oils.
https://mobiloil.com/en/motor-oils/mobil-1/mobil-1-high-mileage
http://www.valvoline.com/products/brands/maxlife/full-synthetic-motor-oil/3
http://www.royalpurpleconsumer.com/products/hmx-high-mileage-motor-oil/
http://images.oreillyauto.com/parts/img/large/oro/hi-syn5-30.jpg
If someone has the link to PlatinumHighMileage info, please post it.
I don't like to let the camry go over 5,000 miles between oil changes due to the fact that this year engine has a sludge problem. I have no sludge in my motor, and I would like to keep it that way. I have talked to Toyota (not the dealer) and they have told me my service intervals is what is keeping my engine from building up sludge. When I use to use dino oil, I changed the oil every three months. One time I only had 700 miles between oil changes during that three month period.
I have used regular 87 octane the entire life of the vehicle and have never had a problem. I'll switch to 91 and see what if anything changes.
There is no need to add any oil during my 4 month intervals.
Thanks for the great information...