Since i have owend my Trans Am i have always used syn 5w30 in the car. Either Mobil 1 or Pennzoil.. Motor was always quiet.

Now ever since i had my cam installed (2007) I still use 5w30. Put i have the sewing machine sound. I have the wrong size PRs. They are jsut a little to long. I got the 7.425s when i should have gone with the 7.4s..

But my question, being that 10w30 is a tad bit thicker than 5w30, do you think it will quiet the valve train down a bit? Seems to have gotten a little bit louder

What do you all think? BTW car is not a DD, i put on about 1,500 miles a year..

Thanks

 

I would actually go in and get those PR's out get the right size PR's and you'll see all your issues go away promise. No need to change oil because what the wrong size PR's are going to do to your car no oil is going to help.

 

The operating viscosity of those two oils are the same so there is really only a difference at start up.

My valvtrain is a little noisy too with 7.4's no mill GM MLS HG so my ?? to you is have you measured. I didn't I just went with what TSP said was good....

But oil wiil not make it quieter to answer your question. Actually a thicker oil would bleed the lifter down slower and make it noisier in theory....

 

Like you, i did not measure either. I did the same thing you did. I listened to the advice of TSP..

So i am now wondering if i shoudl go with 7.350 PRs then???

 

The only way to know for sure is to measure. As for oil, as previously stated, the two oils are the same viscosity at temperature. If you are looking for a higher viscosity oil, German Castrol 0W-30 has about the highest viscosity I have seen that is still within the 30 weight range.

 

Your best bet is to get a PR length checker and get it spot on instead of guessing. The proper length PR and correct preload should silence it some, but I wouldn't expect total silence out of your valvetrain.

As for switching to 10w-30, that won't work. Some have had good experiences with German Castol though due to its viscosity.

 

Damn you vettenuts, you beat me to the punch!

 

That GC shiit is that, shiit. I ran the made in Germany oil in my car when i had 25K miles on the motor and the car was stock. The valve train with that oil was louder than it is now with the cam

 

HAHA!

vettenuts knows his valvetrain stuff. I have several of his posts bookmarked....

 

Find me an oil that someone hasnt bitched about and Ill use that.. good luck.

 

you got a point there

 

How Many Miles Are On the Valve Springs? And, What Are They Rated?

 

8k on valve springs. They are the PRC dual valve springs rated for .650'' lift..

 

GC is not ****. Obviously, you're looking for someone to tell you that your reality can be realized by using 20W-50. She'll be quite then. Jut don't plan on cam & rod bearings to be happy in a daily driver. Unless, of course, you have a pre-oiler & run your oil temps @ 280*F.

Go to Bob is the oil guy. Use oil analysis will confirm that GC is not ****. You're trying to use oil to quiet a valvetrain. That's not what oil is for. Set your valve train up correctly & use a proven oil as confirmed by used oil analysis.