[cd8000]

Okay, I have about 210k on my Camry.
I have a daily commute of 20 miles a day on the freeway with the awesome 4pm rush hour traffic moving at 5 miles an hour. You can literally run home faster than drive!

So I ran Castrol GTX 10w-40 white bottle for 3,000 miles. Did a oil change and it was quite dirty. Must be the extra idle time on the freeway.
I run Mobil 1 Synthetic 10w-40 in the winter time for a slightly better flow.

Should I change to Mobil 1 Synthetic for 5k miles or should I keep using Castrol GTX and change at 3k?

Any ideas?
By the way I have used almost every name brand oil and my engine seems to be fine with castrol and mobil 1 synthetic. For instant pennzoil, it knocked about 5 seconds before oil pressure rose. It felt like a new oil change, had about 700miles on the oil, and it happened once.

 

[mcgowaw]

i like castrol. used to use it before i switched over to wallyworld tech high mileage brand for all my vehicles.
never tried synthetic, especially on my cars since they're all high mileage vehicles.
if you got 210k on the odo using castrol and it doesn't burn any oil between changes, i'd say keep doing what you're doing.
tony

 

[OBwan]

First if you like what you are doing and satisfied with the results, why change?

But, if the car has no leaks and doesn't burn oil with synthetic I personally would go with that and change the oil every 5k miles.

I recently pulled the valve cover off my wife's BMW and after 160k miles with Mobil 1 5W30, I was shocked. It looked brand new. No sludge, no discoloration and no residue of any kind. I've never got that performance out of dino juice of any kind.

 

[tef]

I'd go with synthetic every 5000 miles. I personally believe synthetic is sooo much better than conventional it is worth the extra cost. 5000 miles is overkill anyway, especially with synthetic. Even conventional oil will last 10,000 miles. Of course everybody has an opinion and you can find an opinion supporting any decision you make. There are limited real world tests of oil. The only one I found showed conventional oil lasted 10k. Any choice of oil you make less than 10K will be fine.

As an aside, I drive a 1999 Chevy S-10 for work driving 300 to 500 miles per day. They schedule conventional oil changes every 10K. Often the oil changes don't take place until long after reaching that mark.

 

[Stillrunning]

So I ran Castrol GTX 10w-40 white bottle for 3,000 miles. Did a oil change and it was quite dirty. Must be the extra idle time on the freeway. I run Mobil 1 Synthetic 10w-40 in the winter time for a slightly better flow.

Why are you using 10W-40 - especially in winter? Where are you located?

Should I change to Mobil 1 Synthetic for 5k miles or should I keep using Castrol GTX and change at 3k?

No one can answer that. Dirty oil is not a sign it needs to be changed. If you want to know how your oil is doing then you need a Used Oil Analysis (UOA).

 

[MrGiggles]

It really doesn't matter as much as you think. All brands have to meet the same requirements.

I'm not sold on synthetics. They burn at a faster rate in my car, and are much more expensive to top off and buy initially. In a new car, they're just fine, but not that well suited for engines that are nearly 20 years old.

You will probably come out ahead money-wise with M1 and a longer interval.

 

[cd8000]

Why are you using 10W-40 - especially in winter? Where are you located?
No one can answer that. Dirty oil is not a sign it needs to be changed. If you want to know how your oil is doing then you need a Used Oil Analysis (UOA).

I know that dirty oil is not a sign that needs to be changed but when you have bubbles forming and the oil feeling not right, I rather change it before something else happens.
I live in California where the temperature never drops below 30F. Also this car has 210k.

 

[bwechols]

If I were in your position, I would stick with the 3000 mile interval. I change at 5000 miles, but I drive about 85 miles a day and almost all of that is at 55-70mph. You have to consider how much extra run time you have sitting in traffic that is not reflected in your mileage total. Personally, I stick with the dino. I don't think there's a need to switch on older, high-mileage vehicles like mine. If I bought a new car, I would probably run synthetic from the get-go.

 

[tedmich]

There is not a big difference between "synthetic" and regular oils in the US. This is, in part, due to the fact that almost no labeled "synthetic oil" in US uses actual synthetic PAO base stock. After Castrol won its lawsuit everyone started using hydro cracked Base III (modified) dino oil and calling them "synthetic" in the US. They'd be fools not to as its soooo much cheaper.

The EU has hung tough with a CHEMICAL definition of synthetic, and not a LEGAL definition; it is illegal to sell base III oils as synthetic in the EU.

The only real PAO based synthetics are (usually EU made) and quite expensive. So no, US "synthetic oils" are not substantially different performance wise than US non synthetic oils as they are largely made with the same stuff.

Real PAO based oils are superior and cost it.

12 Qts of 10w-60 Shell Helix oil for your Ferrari Enzo is $250 online or 2-3 times that at the dealer...

 

[71Corolla]

There is not a big difference between "synthetic" and regular oils in the US.

There is a huge difference when doing a cold flow test a conventional oil will take forever to pour out of the container at -30°C. I've done some testing myself at around -30 this video backs up my experience Mobil 1 flows the best.

 

[Stillrunning]

but when you have bubbles forming and the oil feeling not right

If you have foaming then you may have overfilled and the crank is churning the oil or you have cavitation of the oil pump. Do you know your oil pressure?

Also this car has 210k.

My camry has over 230K and I use 0 -30 all year in NC. Did you just start using 10w-40 when it turned over 200K?

 

[tedmich]

Cold pour temp is the most obvious advantage of true synthetic oils over various petroleum based oils. Not so much of an issue where I live! >

That version of Mobil 1 seems to have a higher percentage of PAO than some other versions of Mobil 1. Mobil has chased the $ and now blends their PAO with some unknown fraction of the base III oils, and as a result I believe they can't sell it as synthetic in EU.

For comparison check how vintage (100% PAO) Mobil 1 flows in this ad from the 1980's at -35 degrees. Not sure if its F or C (at -40 they are equal)

As to Royal Purple and Amsoil, they have many MBA's asking themselves "how much profit would we like to make selling oil in the US that we are not legally obligated to add any expensive PAO or ester (true synthetic) base oils to in order to label it as "Synthetic" and charge a premium price for it?"

The answer is usually: "more" :frown: and the cold pour test results out them as liars.

 

[cd8000]

Got the oil changed with 10w-40 Castrol GTX. Decided to keep running that instead. Drained the oil and topped it off.

 

[cd8000]

If you have foaming then you may have overfilled and the crank is churning the oil or you have cavitation of the oil pump

Found out that I accidentally overfilled the crankcase by 1/4 of a quart above full. I serviced the car and made sure that it was not overfilled.

 

[Toyota_JP]

I'm in SE Texas where it only gets below 30F occasionally in the winter but 90-plus is the norm for summer...and the humidity stays high. I have run Penzoil 10W-30 year-round. My change interval is 5,000 miles but I seldom have stop-and go traffic. I replaced the valve covers at...maybe 320,000 miles and it was really clean under there.

I run a Castrol synthetic in my Kohler lawnmower engine so my lackadaisical attitude toward changing small engine oil won't hurt so much...and because small engines run pretty hot. I'm impressed at how high on the dipstick synthetic oil will climb. It sure has a strong adhesive property.

 

[Kingdom934]

Just use the correct oil and good/decent filters. You should be fine.

Conventional oils under stop and go I would be erring on side of 3K/4K. Again, it ultimately depends how much time is on the OCI. Since traffic here is so bad (a 20 minutes drive takes 100 to 120+ minutes sometimes for me!) I try to keep the OCI conservative or when the oil is getting low.

For what is worth, my friends use conventional 5-30w with fram filters. I try to keep their OCI around 3K but been changing at 5K. No issues so far.

I personally run M1 Synthetic HM 5-30 in all my cars including my 85 Camry and 87 Cressida with name brand filters. Guess it's more of a piece of mind, but I do push my engines hard.