Black94Z28

iTrader: (12)

I'm running mobil one synthetic 5w30 right now, and someone told me that is too thin of an oil. Is that true? i need to seafoam the engine and then do an oil change. any recommendations?

LM97Z

iTrader: (4)

My 158XXX mile LT1 runs 10-30 synthetic, that should be all you need.

letsrun97z

iTrader: (7)

look on your oil cap it says 5W30 i was using Mobil one for awhile but i have pressure problems and that crap thins too fast so i use 10w40 penzoil

buffman

iTrader: (9)

any 30 weight range oil will fine. Probably any 40 weight oil also. the first number is just the oils cold pumping viscosity, and if you live in a warm climate, not really a concern.

caldercay

Royal Purple 10-40, in my ~160k mile car, and considering the searing
~100 degree heat waves we get.

BTC

German Castrol is supposedly a very good oil for the LT1.

1994Z28Lt1

iTrader: (1)

as long as your still maintaining 15-20 psi oil pressure at hot idle dont mess with it, so many people get overly concerned about oil pressure, remember the lt1 has tight bearing tolerances from the factory, and the pressure is just the resistance to flow through the engine, the volume of oil being pumped is important and going to too thick of an oil is just as bad and going too thin

for reference GM recommends
atleast
6 Psi at 1000 rpm
18 Psi at 2000 rpm
26 Psi at 4000 rpm

if 5W30 keeps you above those specs there is no need to change to a thicker oil

lt1noob

iTrader: (4)

mobil 1 is a thin oil but a good oil. the only reason people talk **** about mobil 1 is because they now use cheaper (for a lack of a better word) ingredients in their oil. it still is a good oil but there are better oils. royal purple would be one of those better oils, among others which im sure people will tell you about.

daniel6718

iTrader: (36)

valvoline straight 30 all the time here in tx

Smokeshow_2006

iTrader: (3)

If my gage is accurate, and thats debatable, My 160xxx lt1 has 35psi hot idle, and 75-80psi at wot, with good ol 10/30 dino oil.