My car, 94 Z28 with about 33,500 on it has been ran with Mobile 1 Synthetic. I was told Castrol Syntec was a very good motor oil to run as well. Would it be ok to run the Castrol Syntec, since it is part sythetic in the engine that has always had Mobile 1 Synthetic?

 

There's nothing wrong w/ switching brands.... I'm just wondering why you would want to switch from Mobile I???

Synthetic oils are the best IMHO.

 

I was told that over a period of time, Mobile 1 tends to gum up worse than Castrol Syntec, I was just wondering if switching from the synthetic Mobile 1 to part synthetic Castrol Syntec would hurt anything?

 

Both are good oils as far as empirical studies I've seen. I use the German Catrol Syntec 0W30 with good results. Switched from Mobile 1 5W30.

 

I'm sure you'd be fine by switching. Most cars from the factory are running non-synthetic and then switch to synthetic. I don't see why you couldn't do the opposite