Mobil vs Toyota Engine Oil ??????

**StockEngine** · April 1st, 2016 02:11 AM

Better stick with the same viscosity....

15w50 is too thick imo.

**Dezaremos** · April 1st, 2016 02:21 AM

Originally Posted by Stigg ma

its true, caltex is the supplier of oil and fuel products of Toyota motors Philippines (special thanks for vios club of the Philippines for organizing the plant tour)

read the users manual, follow the specifications indicated there, engineers did not waste time just to figure out what to write there which they are legally liable if incorrect...

why does toyota semi syn is 15w50 while caltex semi syn is 10w40 .... they should have the same viscosity since toyota is a rebranded caltex oil right ???

**StockEngine** · April 1st, 2016 02:24 AM

Originally Posted by Dezaremos

why does toyota semi syn is 15w50 while caltex semi syn is 10w40 .... they should have the same viscosity since toyota is a rebranded caltex oil right ???

Different supply/supplier.

**RomeoAlpha** · April 1st, 2016 02:37 AM

Originally Posted by Dezaremos

why does toyota semi syn is 15w50 while caltex semi syn is 10w40 .... they should have the same viscosity since toyota is a rebranded caltex oil right ???

hmmm, just check 15w-50 is their regular oil. i am using toyota FS - 5w40. ung semi synth nila 10w-40, ung regular oil 15w-40, ung jurassic oil nila na pinakamura is 15w or 20w-50 ata. pero bihirang casa nagbebenta nito.

i worked with GT CAP group before circa 2008 - 2012 and yeah they are using caltex products for oils kung sa planta kukuha si dealership. so based on my estimate 60 to 70% of the oils they have is from CALTEX. although some dealership(s) (depende pa sa may ari) just got the oil somehwere else na approved ng planta.

**Dezaremos** · April 1st, 2016 03:15 AM

Originally Posted by RomeoAlpha

hmmm, just check 15w-50 is their regular oil. i am using toyota FS - 5w40. ung semi synth nila 10w-40, ung regular oil 15w-40, ung jurassic oil nila na pinakamura is 15w or 20w-50 ata. pero bihirang casa nagbebenta nito.

i worked with GT CAP group before circa 2008 - 2012 and yeah they are using caltex products for oils kung sa planta kukuha si dealership. so based on my estimate 60 to 70% of the oils they have is from CALTEX. although some dealership(s) (depende pa sa may ari) just got the oil somehwere else na approved ng planta.

i googled it & went to toyota casa .. their regular oil with green label is 20w50, their synthetic blend with red labe is 15w50 and their fully synthetic with yellow label is 5w40 ....

my question is, assuming two semi-synthetic oils are rated with the same 15w but differs on the last number (15w40 vs 15w50) .. Does the 15w50 offers better maximum heat protection at operating temperature (40 vs 50) ????

Why is 15w50 thicker than 15w40 when they have the same 15w winter numbers ???

**StockEngine** · April 1st, 2016 03:25 AM

Follow manufacturer recommendation

Yes a 0w50 will protect well for a a racing car or ferraris but they do operate at a higher speed.

Your old engine probably idles more in traffic than anything. Even if you rev it to 4000rpm a 40 weight oil will be good enough to protect your engine...a 50 weight will not have better protection than the 40 weight.

**admiral88** · April 1st, 2016 09:02 AM

I'm also using Mobil 1000 15W40, and it's way better than 20W50. Every 5,000km oil change, surely, I'm not going back to 20W50.

**XTO** · April 1st, 2016 09:33 AM

Originally Posted by Dezaremos

I'm using an old AE101 Corolla GLi 1.6 4afe engine .. The rated oil for this engine as per research on the internet is a 15w40-10w40 ...

You'll be fine wtih 10W40 .

**Wh1stl3r2** · April 1st, 2016 06:27 PM

Originally Posted by Dezaremos

my question is, assuming two semi-synthetic oils are rated with the same 15w but differs on the last number (15w40 vs 15w50) .. Does the 15w50 offers better maximum heat protection at operating temperature (40 vs 50) ????

Why is 15w50 thicker than 15w40 when they have the same 15w winter numbers ???

Having the same winter numbers only means they should more or less behave the same way during cold starts. The actual oil thickness at operating temps is the 2nd number. Thicker isn't always better, thicker oils get you less fuel economy. Also, with group 1, 2 and 3 oils the bigger the difference between cold and hot numbers, the higher the amount of viscosity improvers. These VI give out eventually and when they do, the oil will behave more like a monograde oil with the hot number viscosity at startup. That's one reason why mineral/semi syn oils should be changed more frequently.