Oil

[trainguy1989]

Is it alright to switch from Mobile 1 to Castrol GTX if Mobile 1 was used for a while? I ask because I heard it was bad to switch back to dino oil after synthetic has been used for a while.

Thanks,
David

 

[sho_ted]

You can switch back and switch again whenever you like.

 

[DJSHO91]

My car's original owner had used Mobil 1 since it was new. I bought the car at 150k miles and switched to Castol GTX 10w30 and have been using it ever since. Just recently replaced the valve cover gaskets and everything looked like it was 14k miles instead of 214k miles. Go for it!

 

[houghton33]

Its always bad to switch back to Dyno oil because it is an inferior product.

 

[K-Dawg]

Yeah, every engine with non-synthetic fails eventually.

David, you should have no problem going back to regular oil. However, I use synthetic because I feel better about going longer between oil changes.

 

[nothingtoseehere]

Its always bad to switch back to Dyno oil because it is an inferior product.

Synthetics advantage is extended change intervals. So if you are using Mobil1 and changing every 3K, you are throwing money away.

****, I use Motorcraft and change every 5K.

You should be fine switching back, as said.

 

[DJSHO91]

Yeah, every engine with non-synthetic fails eventually.
QUOTE]

Well, 215,000 miles and still all-original internals. No tics or knocks. Yep, it's just falling apart!

Seriously, one issue that is often found with synthetics is how it effects seals and gaskets on higher-mileage street engines. I also believe, as a proponent of 3-5k mile oil changes for street engines, that the longevity values of synthetics are negated. Thus the cost vs benefit weighs in the favor of GTX. You also have to understand that, with todays additives, even "conventional" oils are a "synthetic blend".

 

[houghton33]

The superiority of synthetic oil is that it flows much better cold, lubricating all the engine parts better sooner so you don't have dry starts. And for those of us who like to thrash the engine on hot days for hours at a time, synthetic resists thermal break down and maintains stable film strength at extremely high temp. Why do think they put it into the world's most expensive engines?

 

[sho_ted]

that would be the only reason.

Its always bad to switch back to Dyno oil because it is an inferior product.

 

[DJSHO91]

The superiority of synthetic oil is that it flows much better cold, lubricating all the engine parts better sooner so you don't have dry starts. And for those of us who like to thrash the engine on hot days for hours at a time, synthetic resists thermal break down and maintains stable film strength at extremely high temp. Why do think they put it into the world's most expensive engines?

My comments were directed against an oil being used in a street-oriented motor. In street use, even run agrresively, Castrol GTX has all the nessicary additives that provide the stable film strength while resisting thermal break down. It also has additives to provide superior protection during dry-start.

Castrol GTX Key Benefits

•Castrol GTX exceeds demanding U.S. high shear and stay-in-grade requirements for viscosity breakdown protection.
•Far exceeds the demanding U.S. requirements for viscosity breakdown in every grade!
•Engineered to provide maximum protection against viscosity and thermal breakdown!
•Anti-oxidants, detergents and dispersants provide unsurpassed protection against thermal breakdown.
•Exceeds passenger car and gasoline light truck requirements for the protection of gasoline and turbocharged engines where API SM, SL, SJ or SH is recommended.
•Formulated to exceed engine protection requirements of Ford ESE-M2C153-G and F, GM 6085M, Chrysler Corporation MS-6395H.

Product Data Sheet

 

[sickSHO96]

Nice commercial.

 

[sho_ted]

nice cut/paste from their website?

 

[DJSHO91]

nice cut/paste from their website?

This is simply a statement of the quality basis of the current motor oil specifications. When Mobile 1 first came out, it included additives that were unlike anything else on the market. This was in addition to the synthetic base product. Today most SJ or SH graded oils include those very same additives. It's not that Mobile 1 isn't a high grade product, it's that there just isn't the differentiation between it and the other available products(as there was in the 90's). The major issue to understanding with today's oil products is that there is no longer any pure "Dino oil" products available that meet SH and/or SJ ratings. Everything is, at the minimum, a "blend" today.

As to the "cut/paste" and "Nice commercial" references, I'm sure you would find a completely "non-biased" description on the Mobile 1 site. Also, remember that Castrol also sells synthetic oils. My point is that with a street engine, and using a 3k/5k oil change routine, the cost factor of synthetics out weigh any perceived durability benefits. :thankyou:

 

[sho_ted]

SH SJ are way outdated specs.

 

[DJSHO91]

SH SJ are way outdated specs.

These were the rating levels when the additives we are speaking about started showing up. Look, I'm not trying to tell you not to use Mobile 1. All I am trying to express is the reasons I don't feel the need to do so. Neither of us is wrong, it's just personal preference.