100K, safe to switch to Synthetic?

I live in ventura.... a similar (slightly cooler more Mediterranean climate than you, but find myself in 110* weather in the desert, and 0* in the mtns) and switched to 0w-30 after reading this

https://bobistheoilguy.com/motor-oil-101/

its many chapters, but WELL worth the read to understand why 0w-30 is not only 100% safe to use in all climates, but is better for "cold" motor protection (your motor at 100*f in your hot climate is still technically very cold)

from chapter 2

 

As I read earlier some one said; "You do it your way, I'll do it mine--if one day we meet I'll buy the first pint, the next one is yours"...

 

I agree with nd4spdbh.

People think that 0W-30/5W-30 oils are lighter than say 10W/30. They are for COLD starts. The first number is a WINTER rating. The 2nd number is a SUMMER rating - the viscosity the oil will be at when warmed up.

I don't care if it's 80F or 10F outside. The first couple of seconds the engine runs are the most damaging. 0W-30 deals with this better than 5W-30 or 10W-30. Once warmed up and under way, 0W-30 deals with heat as well as 5W-30 or 10W-30.

Mobil has a good discussion about this at their web site. I trust their knowledge of oil more than peoples gut feeling on car forums.

 

Old wives tale, synthetic does NOT create big oil leaks from small ones...

 

OP.....don't over think this. It's easy to do around here. Get yourself some M1 HM 5w-30 and call it a day. The HM contains seal and gasket conditioners. That's the only reason I suggest it...and it's available everywhere

 

it just leaks more

 

https://www.tacomaworld.com/threads/mobile-1-synthetic-motor-oil-rebate.478908/ + Walmart=Win

 

I have experienced this on two vehicles; my wife's old '98 RAV 4 switched to 10W-30 synthetic at 85k miles it developed a significant weeping from the rear main seal, enough to create 1" or so spot on the garage floor overnight, switching back to conventional oil (Valvoline MaxLife) stopped it. We had that car 'til 235k miles and it never leaked again.

The second was my brother's '03 Mustang GT with 90k miles; front main this time and again switching back to dino juice tightened it up.

Also, but not entirely synthetic oil related my '06 Honda Silver Wing with 9100 miles leaked when I filled it per the specs with 10W-30 synthetic, however I found out that a misprint in Honda's service manual had listed the recommended engine fill capacity incorrectly. It stated 2.3 qts (with a filter change) but should have been 2.1 qts. The extra oil was being flung about the generator stator housing and weeping out through two rubber wiring seals at the top of the side cover--draining out that additional 6-1/2 ounces stopped the leaks...

 

Maybe I didn't read the post correctly but I don't see where orezona said anything about synthetic oil creating big leaks out of small leaks, he writes that a lower viscosity oil will make small leaks, big leaks, (not sure if he is correct or not, but that is what I read) I do agree with his comment on conventional oils, I have put 100's of thousands of miles on vehicles using conventional oil, using synthetic and changing every 5k is (for lack of a better word) stupid. jmop

 

Don't challenge some folks... they may actually try peanut oil.

 

Yes... yes it is shit... man...

 

Use the correct weight your vehicle calls for and you can use whatever "blend" you want. If you want longer OCIs, use synthetic, if not, use conventional. It's up to you and what you want to spend.

At the end of the day, do you drive enough that extending the OCI will help or are you going to change every 3k miles anyway? Personally, Toyota "recommends" 10k miles or once a year for my Turd gen... I don't like going that far, so I change every 6 months as that's when I would need to rotate the tires. That's me... you may drive 1000 miles a week... I just turned 10k at just over one year. I use Amsoil XL as I don't see the need to use anything more due to cost and I'm going to change it out every 6 months anyway.

As long as you use the weight your engine calls for, you're fine. All a synthetic will give you is longer OCIs, so that is a decision you have to make on what you want to spend and how often you want to spend it.

 

https://www.youtube.com/watch?v=kKwpj2N0Eos

 

I've heard of engines blowing up if you switch to synthetic after 100,000 miles...I read it on the internet!

 

I read in a post somewhere that a guy in a bar told the poster it happened to the neighbor of his uncle's cousin's brother-in-law's nephew because he used Walmart oil...

 

go spend your money on fancy oil if it makes you feel good

after a million miles with no issues with dino oil its hard to convince me other wise

 

True story, you can dump a whole bag of sugar into your gas tank and it actually WON'T kill your engine.

/no really, it wont blow it up, just create more carbon buildup on the cylinder heads... which isn't good in the long term but not an immediate, spectacular engine failure

 

Valvoline does make a full synthetic MaxLife. I'll likely use it for my next oil change, if I can find it.

 

I love all the engine experts on here. One of my professors in college is probably one of the brightest, most engine knowledgeable people on the planet and in my internal combustion engine class someone asked an engine oil question and his reply was a simple "just use an SAE approved oil of the manufactures recommended viscosity". This isn't an egghead professor, that suit he is wearing in the picture was wadded up in his desk drawer when I was in school, he usually wore work pants, work shirt and suspenders because he played with engines all day long. This is part of the group of people that caught Volkswagon cheating on their emissions testing.

There isn't any magic combination, just take care of your engine right and it will take care of you.

 

I did grad work under John Heywood (

$474 Internal Combustion Engine Fundamentals

The Fundamentals of Internal Combustion Engines) and with slight modification (i.e. using a viscosity as appropriate to your operating conditions) I can agree with the above. Contemporary manufacturer's "owner's manual" recommendations are dumbed down "one-size-fits-all" generalisations. Not that long ago before consumers became brain dead and meeting CAFE requirements became priority #1 engine oil recommendation were specified in charts such as that below:



I have heard all the arguments about advanced machining, clearances, hydraulically controlled valve timing. etc. but the fact is nothing has changed so dramatically that selecting an optimal motor oil is a universal singularity regardless of climate, service duty, etc.