z_speedfreak

iTrader: (3)

I just switched from Mobil 1 10w-30 to royal purple 10w-30 the other day after I was reading some posts about how the M1 leaked allot and how some people's engines sealed back up after switching to RP or the german castrol. I have a slow drip coming from my rear main and was about due for an oil change anyways so I figured I'd try a brand switch before I pulled any gaskets. lol all I got when I asked around about the german castrol was funny faces from the autozone monkeys so I settled for the RP. then yesterday as I was cruising down the highway, right as I got 50 miles into the new oil I picked up on my oil pressure gauge fluctuating the slightest amount probably not even a 1#, the needle was just barley twitching. then the next time I came to a stop when the engine idled down so did my oil pressure by atleast 5#'s, the first time I've ever seen it go below 40. im a little concerned about it now, I've never had any problems out of that engine besides for the leaky rear main -knock on wood- and it looks like I'll have to pull it cause now I have some purple oil drips on my floor. it could be a mechanical problem although it runs like a champ.. but im curious if anyone else has lost any oil pressure with royal purple or when switching brands?

BTC

I don't think I would worry about it. If your idle pressure has always been over 40, that's very high, and probably not normal for an LT1. If you're worried, I would put a mechanical gauge on it and find out for sure what your pressure is. It's possible that your gauge is providing false information.

z_speedfreak

iTrader: (3)

I might be having a brain fart cause I drive two vehicles, LT1's oil pres gauge goes to 80 right? or is that my other car now lol.. 80 or 60 either way its now fallen below the half mark which is a 1st in the 4years I've owned the car.

BTC

I believe 40 is the mid point on the LT1 gauge. I would guess most LT1's idle pressure is probably below 20, but I'm sure there are exceptions. That's what makes me think there could be something wrong with the readings you're getting from your gauge. You could confirm it with a mechanical gauge.

Is your car stock?

Paul Bell

iTrader: (9)

Assume the idiots at Autozone are idiots. Look at the oil and find the Castrol that's 0/30. It'll say "made in Germany" on the back.

You're not saying in your post exactly what oil pressure your gauge is reading.

z_speedfreak

iTrader: (3)

im pretty sure the internals are stock..

z_speedfreak

iTrader: (3)

so only the 0w is made in germany? theres no german 10w?
sorry, my oil pressure is usually just a tad above 40, now its ~35ish

BTC

The German Castrol is only available in a 0W-30. Oil freaks love that oil, and it's supposedly great in the LT1.

z_speedfreak

iTrader: (3)

oO yeah I've heard the rave reviews, didnt know it only came in 0w.. yeah im not going to put that in an engine thats going to hit 100k this summer

BTC

It won't hurt it. 0W is the cold viscosity.

camar0corey

iTrader: (22)

Yeah I think at idle my oil pressure is only around 15-20? Its maybe around 35-40 at idle when its cold. I've got 165k on mine, been running royal purple for about 30k. Every now and then I see the 1-2# fluctuation you are talking about.

leadfoot4

iTrader: (1)

Did you install a different brand of oil filter? That might have something to do with it.

Chief Z

Oil pressure drop of 3-5 psi seems normal. RP is a lower viscosity oil, which would cause a corresponding pressure drop. Lower viscosity = less drag/more hp. This is balanced by the superior film strength of RP which protects parts during start up. (I let her really warm up - just to be safe. If you have a leak, RP is going to leak more, 'cause it is thin. Pull your rear and change the gasket.I would not sweat a little oil pressure difference...yet.

leadfoot4

iTrader: (1)

That's a LOT of work, just to compensate for a thinner viscosity oil!

z_speedfreak

iTrader: (3)

yeah I'l do the gasket when I pull the clutch, time for a new disc so..
and its the same wix filter I always use