Once 5w30 and 10w30 get up to temperature they are the same oil. They both have the properties of a straight 30 viscosity oil. I would just stick with the 5w30 since it moves a little faster on start up then 10w30 and that is what you have been using before.

We use Max Life ATF in our bulk tanks at the shop and it is very good stuff. Nearly universal application and several people have come back saying their trannies seem to be shifting smoother after swtiching. Don't know how much of that is related to just having new fluid in the tranny and how much is related to having the Max Life ATF.

Mine does shft a lot better but my car is still hesitating when I try to rapidly accelerate at warmer temps so... perhaps my fuel pressure regulator? I just wish I knew where it was at lol. Oh should I go ahead and put synthetic oil in?

I had used Slick 50 in my Monte SS years back. The stuff did work. I never did any dyno tests or anything like that, but I did notice a 200 rpm drop in my cruising speed. It did seem to significantly reduce engine friction in that regard.

That was when it was still like $50 per quart and they "advertised" that one treatment would last for years. What has been since found out, though, is that when you drain the oil for an oil change, you basically lose the benefits of the Slick 50. It has come down in price a lot and they suggest usage intervals anywhere from every oil change to once a year.

I really don't know what the comparision of Slick 50/regular oil vs. all synthetic would be. I have started using Mobil 1 in my car and feel it is doing its job. I have not noticed any change in cruising rpm'*, but I have noticed a slight increase in fuel milage.

Basically, you need to decide if the total cost involved to use Slick 50 is worth your piece of mind.

Jay

Couple of points on this and the preceding post:

1) If Slick 50 actually achieved a reduction in friction, you should see an _increase_ in rpm, not a decrease. However, engine speed to road speed is determined by the transmission torque convertor slippage (assuming it'* not locked in bypass by the TCC solenoid, which at highway speed it should be), and trans fluid is not touched by the Slick 50 in the crankcase. When it is in TCC lockup (cruising speed in high gear), engine rpm is directly, physically tied to road speed through the drivetrain, and still has no correlation to the type of oil in the crankcase. Friction reduction might help in acceleration, top-end speed and cold-starting performance, but not in determining what engine speed occurs at what road speed; that'* a straight mathematical number.

2) The fuel pressure regulator is at one end of the fuel rail on top of the engine, towards the driver'* side. It'* a small round metal diaphagm with a vacuum line plugged in. With the engine off, you might want to unplug the vacuum line and make sure it'* dry inside: if it pees gasoline at you, it'* leaking and you'll want to replace it as soon as possible.