Hey,
I've got a question About these four brands. My truck has 94,000 miles on it and i'm woumdering what synthetic to switch to. I've always used castrol 10w-30. I want to switch to a synthetic in thought to get more "life" out of my vehicale. I did switch to syntec for a while but then switched back to gtx. Just woundering which oil would benifit the engine and truck the best.

 

Stay with Castrol dino at the weight you have used and change it regularly. If you go synthetic now, you may find that the engine will use oil, in response to which you'd use a heavier weight which may not be the best for lubrication purposes. Maybe, maybe not.

If you don't drive in an extreme environment and don't race or run hard, you'll likely not experience much benefit from synthetic oil. You'd have to sample and test to really determine that. If you're up for that, go for it. Otherwise, 3000 miles on dino oil will serve you well.

 

I would stick with Castrol GTX given the high miles on the truck. I'm not sure you would get much benefit from the MUCH more expensive oil and Castrol GTX is good oil in its own right and has obviously done well for you. If it ain't broke, don't fix it.

 

I agree,stick with the Castrol GTX.It is excellent oil and actually outperforms Syntec.:-)

 

Mobil 1 is the only true PAO based oil in your list unless by Ams you mean Amsoil. Then Mobil and Amsoil both would be. Castrol Syntec is a Group III oil and therefore is not worth the money in my opinion. I believe Chevron is also Group III.

Mobil tends to run as a thin 30 weight oil and Castrol GTX is in the middle range of a 30 weight oil. Since you want to switch from GTX, then I would have some concerns about oil usage of Mobil 1. Amsoil might be a safer bet. On the other hand if you want to go up to a 40 weight oil, the Mobil 1 0w40 is an excellent choice.

But like the others have said, GTX is a fine oil and so continuing with that isn't such a bad idea.

 

>Mobil 1 is the only true PAO based oil in your list unless
>by Ams you mean Amsoil. Then Mobil and Amsoil both would be.
>Castrol Syntec is a Group III oil and therefore is not worth
>the money in my opinion. I believe Chevron is also Group
>III.
>
Mobil 1 is no longer 100% PAO but a blend of PAO, esters and Group III. Chevron is ester based (Group V). Amsoil now varies by product line (and price).

>
>But like the others have said, GTX is a fine oil and so
>continuing with that isn't such a bad idea.

I agree.

Jim

 

>Mobil 1 is no longer 100% PAO but a blend of PAO, esters and
>Group III. Chevron is ester based (Group V). Amsoil now
>varies by product line (and price).

Jim, my understanding is Chevron switched to a Group III base some time ago. And you are correct, Amsoil 7500 line is Group III (after the Castrol suit), but most of their other oils are PAO.

Since Castol won the suit that says that Group III is synthetic, it changes the market. Many companies have no advantage in offering a PAO based synthetic because Group III is so much cheaper to make and they get to call themselves 100% Synthetic right next to Mobil 1 and charge the same.

 

If you gotta use something that says Synthetic on the label, try Shell Rotella T 5W40 available at Wally world for about $13 a gallon. It has a high flash point, good TBN, and it doesn't cost a fortune. Unless you are considering extended drain intervals, wht=y spend the coin?



Reggie

 

I don't think I'd change to Synthetic now...

You may start using more oil, and start finding leaks that weren't there before.

Larry