Home Forums Hunting & Shooting Hunter's Campfire Synthetic Motor Oil

Dad owned a garage in West Texas, a dusty climate. He was adamant about frequent oil changes, and generally changed the oil every 1000 miles or 3 months. I've relaxed a bit since those days, but I also drive more, too.

I've used Mobil 1 since Ford starting using overhead cam engines, and have had good service. Of course now the 04 has some noisy timing chain issues, with 175k on it, but that's a known issue with early 5.4L engines.

The new truck has the Ecoboost turbo, so it too gets synthetic oil, to help prevent any coking issues on the turbo. It just had its 3rd oil change with 14k on it. I went in with AmsOil synthetic, which supposedly has the best anti-friction additives you can get.

Old time mechanic told me years ago that brand doesn't matter (Pennsylvania vs. Texas oil... paraffin vs. non-paraffin), just don't change brands once you start using one or the other (kinda like "seasoning" on a cast iron skillet... add it... tear it off... add it... gunk has to go somewhere and change your oil OFTEN.

With that said and with all the fancy additives in oil now-a-days... Rotella in my diesels and old Landcruiser.

Mobil 1 regular on the wife's Prius and Mobil 1 Gold on the minivan which had an unknown oil consumption dilemma when we bought it with 150k miles.

If any of my engines ever fail me over an oil issue I will be disappointed. I expect 400k+ miles out of a gasoline engine every time. 600k+ out of my Cummins 12 valves.

Usually the demise of a vehicle for us is an accident or rust... or unjustifiable cost repairs

That Sir is an excellent point.

I use Amsoil in every one of three trucks and one car, both engine and differentials. However, I also use extended change intervals and used oil analysis (UOA) to determine when, if ever, the oil needs changing.

My GMC DuraMax diesel truck is also fitted with a dual bypass oil filter system. The extra filtration does not necessarily protect the engine, rather it protects the oil, limiting the amount of abrasive particulates. Both the DuraMax and my newer GMC Sierra 1500 with a 4.8L V-8 are filled with 5W-30 Amsoil Series 3000 HD Diesel Oil. The others use Amsoil 20W-50 Synthetic Premium Protection Motor Oil as one is 37 years old, and the other 35 years old with high miles.

A 12 quart case of the Amsoil Series 3000 HDDO costs $93.75 with my discount, or $7.81 per quart. One case is required for an oil change on the DuraMax with the dual bypass filter system.

Synthetic oil has two properties that outperform dino oil, it keeps particulates in suspension, i.e. diesel soot, which improves filtration, and it resists high temperature shear and oxidation better.

However, if the vehicle owner is not considering using extended change intervals and/or UOA, there is no justification for using synthetic oil. Using any quality brand of the correct specification oil as recommended by the manufacturer will provide all the lubrication needed. A more important consideration is the oil filter, only high quality synthetic blend media filters should be used, i.e. Amsoil, AC Delco, Baldwin, Bosch, FleetGuard, MotorCraft (RACOR), Mobil 1, NAPA Gold, Purolator PureONE or Synthetic, RACOR, Wix.

More info than you want: http://www.bobistheoilguy.com/ Click on the oil Forum button and go crazy.

My 2013 Honda CR-V is built for synthetic oil and that's what it gets. Synthetic oil does let the rig start and run better in the winter and the oil doesn't seem to have any problems in the summer.

I think the bigger problem is when to change the oil. Supposedly the synthetic will let you go as long as 12,000 miles between changes. Most techs I've talked to say in Montana 5,000 to 6,000 tops if you are not towing a trailer. I tend to change around 4,000 miles or less. I don't tow a trailer.

Since I tend to push my motors hard, even racing my HD Motorcycle if the race day happens to fall on a day that I am feeling OK, AND because I cannot afford to replace any of the auto's or motors I see good quality synthetic oils along with an occasional PTFE treatment (slick 50, T-Plus, whichever one is available when I get the mind to re-treat) gives me some peace of mind and is doing all that I know to do, along with good filters etc. to make sure my motors and cars and HArley run strong for as long as possible.

Like Wrangler John, I went back to Amsoil series 3000 deisel oil. I used this oil in my 05 Duramax. I went with extended oil changes and changed Amsoil filter every 15k. The first time I went with extended oil changes the oil test said the oil was still good at 46k. I changed it anyway cause I felt it did it's job. The next time I went 39k and it was still good but, again how much do you want out of 10qts of oil. Oxidation was a little high so out it went. Before I went with extended oil changes I was still using Amsoil with 15k changes though... I went back to Amsoil 3000 last week for $112 dollar oil change. Kind of high since Shell Rotella 10w30 worked fine and I changed it according to my oil change warning. I went 12k and 10k oil change intervals and think that is real good for $ 3.50 a qt oil. The reason I am going back to Amsoil is cause my new dealer lives fairly close and he seemed to give me a price break to some degree. The main reason though is it got so darn cold here last winter with the 10w 30 dino I noticed a harder start with the deisel. I have nothing against dino or syth but am convinced the Amsoil 3000 is some very good stuff. I also have said on this sight and other sights, we change oil much more often than needed. I have no issues with any of my cars or truck. Truck has 207k, Dodge Stratus has 137k and I change it about every 10-12k with dino. Sunfire had 178k on it and went 30k changes most of the time with syn and 10 -12 k with dino. I have never had an issue with this method and keep my cars till they die. Not trying ot convince anyone to switch, just my experiences about oil. ALso, air and oil filters are ver important in keeping oil clean.

From my past experiences I would not change to synthetic after 30k on the engine because it may start to use oil when it didn't before. That was over 20 years ago so things may have changed. Synthetic oil keeps your engine cleaner and doesn't break down from heat as easily as crude based oil. I'm a fan of synthetic lubricants.

I've had a couple of times, that I have had times I have done experiments, to test oils.. particularly when an engine or vehicle is up there in miles or was picked up cheap...

In the picked up cheap dept, back around 2000, I picked up an 88 Prelude, exterior and interior were immaculate.. it had exactly 100K on it... and price was $2500.. was putting heavy miles on a car at the time, making trips from here up to Portland and Seattle three or 4 weeks out of the month, and those were honest little 35 mpg jalopies...

Put 4 new Michelins on it, gave it a tune up and radiator flush, pulled the valve cover to look at the top end of the engine...
Looked like someone had just paved it with asphalt....

Took an old spoon I picked up at Good Will, and cleaned out the big spots as best I could... figured 'oh what the hell', engine experiment car....Filled it up with Mobil One OW-40, and figured this was going to be its only oil change, and I was going to run t until the engine blew and see how long that would take us...

Gave it a filter change every 5 K, and added as needed, which turned out to be just adding the little that changing the filter took out....previous life, it had been owned by some chick, bought new in 88 and had an oil change once a year.... 10W30 Pennzoil...( no less)..

Highway miles mainly, but plenty of those were 2 lane Oregon Mountain roads and it is a fun little zippy car, so it tended to get ran hard at times...which doesn't seem to phase a Honda...

one year and 40,000 miles later, buddy is getting divorced and needs a car real bad.... one that gets good gas mileage.. and wanted something he called "sporty".. so he is badgering me to sell him the Prelude...non stop...

he has a budget of $2500, and offers me that. I let him know that is what I paid for it a year before, and 40,000 miles ago..,
he still is begging me.... so I finally give in and let him have it for $2500...

Del is a mechanical idiot, so I have a little pity on him, so I give it a fresh tune up..do a break job on it, flush the radiator, and give it an oil change...since the oil has been in there 40,000 miles...

I pull the valve cover, just to see what it looks like under there now...since it still is using no oil, despite the 40K on the Mobil One...

I was shocked and pleasantly surprised... ALL of that sludge and crap that had been there, after I cleaned up what I could, was ALL LONG GONE! the upper end of the engine was totally clean...

I knew Mobil ONE was good stuff, but that impressed me further...

I threw Mobil One back in there ( new oil change), and typical Del.. he never changes the oil on it, no filter or nothing...

gave it to him with a little over 140K on it, his 20 year old son totals it, just after it had a little over 200K on it...racing someone, going over the mountains on I 5 in winter with snow all over the place...California raised kid.. big surprise...racing on packed snow... and rear ends a semi...

Insurance company gave Del $4K for it...sad end to a good little car....but kids and idiots get ahold of them, they're days are numbered anyway...

but that Mobil One OW40 sure did its job and then some...

I bought a 2008 Toyota Highlander earlier this year. It was the last year in which regular oil (5W20) was standard. My wife's newer Lexus has essentially the same engine and came standard with 0W20 synthetic. When mine needs its first oil change, I'll go with full synthetic.

Now that I'm retired, I only drive about 5,000 miles a year (Yeah, that shocked me, too!) so I figure a filter change a year and the occasional top-off ought to last me a good long time.

only run synthetic, in my GMC, boat and snowmachines


the trucks that are garaged in the winter get dino oil


cold weather and instant oil pressure are a good thing for moving metal parts ime

along with Royal Purple and Mobil 1, believe Amsoil synthetic makes the grade as a true synthetic.


if I lived in a more temperate climate I'd most likely run all dino

on the flip side to the above.. my 94 Camry has 331K on it now..

at 310K I decide to do another one of my 'what if' experiments...

instead of Mobil One, as usual, I decided to see what a long drain period of 20,000 miles would do, using 15W40 Diesel Truck oil would do..

So I did a change with Mobil DelVac 15W40 from Walmart.. I use Purlalor filters from Walmart also... so from 310K to 330K, I ran that, changing the filter every 3300 miles...

vehicle got a lot of highway miles during that period...but analysis sent in with 20K on the Delvac 15W40 came back as the oil was still good, and could be ran longer....

pulled the valve cover on the 4 cylinder in the car, and the top of the engine had no sludge or varnish that built up over that period at all...

I did note that with the heavier conventional oil, the engine didn't quite run as smooth as it did with synthetic, or warm up as quickly on colder days... but at least the heavy duty high detergent diesel oil did a good job...

changing those filters I think helps extend the life of oil quite a bit, especially on the conventional oil....

now experimenting with running low viscosity 5W20 in it during the warm weather and see how that holds up... admit to having half filled with Walmart Synthetic 5W20 and half with their regular dino Walmart 5W20... real close to 2,000 miles on it, as the car will probably roll over 332K this week...

but so far, with 90s and 100 degree temps, the engine hasn't gone thru any of the real light oil so far...which surprises me on an older engine and older vintage...but I am noticing the better fuel mileage as claimed on Bob the Oil Guy's Web Site..

so when I drop this oil at the next change...I'll probably go with a fill of Mobil One high mileage 5W20...I trust the synthetic light weight oil much more than I do conventional..

but hey, it isn't like conventional oil is bad or anything, its just synthetic Mobil One has been sooooo much better...

Every 3500 miles .......dino oil> april till oct ....then the fake stuff the balance/winter (all shell rotalla)... chevy duramax with eight thousand + hours and 98,thousand miles..

Take a typical plastic jug of 10 30 motor oil. Chill it to minus 45 and then tip it over and try to get the contents out. You will need to stand on the container. Reminds me of trying to get the last drop of tooth paste out of the tube.

I run Mobil 1 in all the vehicles, cars get changed at 10k, the cummins in the truck at 15k with filter change at 7500.

Synthetic isn't any more expensive when you get double the mileage out of it vs. dino. Another thing to consider is oil is much more than the base stock, it's the additives that make a big difference in how the oil performs over the long term.

As far as switching from dino to synthetic, there could an issue with some engines with the seals, but that hasn't been my experience. Both the cars have always run mobil 1 and have always gone through a quart or two per 10k, though one has 120k and the other 210k on the odo. On the truck I changed the factory oil at 1k, ran chevron delo for 7500, and have been running mobil 1 ever since. 112k on the odo and doesn't burn a drop.

Oil is the lifeblood of an engine, I can't imagine not using the best.

This^

I like knowing that when it's extremely cold out, the synthetic oil in my crankcase isn't congealed into a slow-moving lump of tar. Synthetics tend to flow better at low temps and are less likely to breakdown at high temps, like when I'm towing 10K at 98F.

there is a reason for the using oil though like you said this was an issue 20 years ago more than now, and the reason was also in your post....the Jeep addicts tend to swear on using synthetic on high mileage old Jeep engines but the first thing they tell you is when you make the switch be prepared to change some seals and gaskets if it starts leaking....the reason? the detergents in synthetic are more effective than dino and its gonna clean out alot of junk including the junk that may have been plugging any small holes in the seals....

course this is less of an issue in making the switch in newer engines since seals and gaskets are much better now but its something to be aware of if your making the switch in a high mileage engine, especially an older one...

I gotta admit, after 15 plus years in Minnesota, I make sure I don't have to live somewhere, that I'd have to deal with that type of weather anymore...

That's my opinion as well, excepting that would run synth in turbos. Outside of that, am unconvinced it makes any difference in a car/truck engine as long as it's changed regularly/when indicated.

Local friend bought a new Jeep Grand Cherokee a few years ago, but went with Mobil 0W40 oil at its first needed oil change...

it promptly starting pissing it out.. he tried several other synthetics.. same results...

he wasn't real impressed with Jeep's "Quality"....

he traded it in on an Acura MDX....problems solved...