Is this oil to thick for my L1

[johnnyboyweber]

I am running Rotella 15w40 in my recently Auto-Rx'ed LS1 and am worried that this oil may be to thick. Pressure is way up. Around 55-60 cruising. Only up slightly at hot idle to about 45. Did not read up on CST until after I changed oil. I have run Mobil's 0w40 synthetic and if memory serves me, pressure did not make a big jump.

Only have 52k miles and the engine is noisier than before. Was trying this oil to see if it would quiet down my ticking and tacking in my engine.

 

[Patman]

In the hot summer time, especially if you drive hard a lot and see 240F oil temps or hotter, then this oil will be fine. If you drive in cooler weather and your oil temps rarely get super hot, then you'd be better off with a 5w30. Let oil analysis be your guide here though, that's the best way to easily see if you've chosen the right viscosity or not.

 

[johnnyboyweber]

Cool. I know that a CST around 12 is generally ideal and this oil is, I believe, 15 or higher. Would increased engine noise be an indicator that it may be to thick.

I live in the DFW area and see alot of highway. I have used oils with CST's around 12 and they seem to work very well with keeping engine noise at a minimum. I was trying this oil to see if it helped quiet it down.

I guess I am just questioning wether or not this oil would be to thick for propper ring clearances. The engine is still pretty tight and I don't want to do anything to change that, at least not rapidly.

Sorry for the long reply.

 

[johnnyboyweber]

Has anyone done oa with this oil in this engine. I've searched and not found too much info.

 

[johnnyboyweber]

ttt

 

[Pablo]

I would run a good 10w30 in Texas.

 

[Mr_Incredible]

JohnBoy, I have a used oil analysis posted from a fill of the old M1 TrSuv 5w40 (now marketed as M1 TurboDiesel). It did well in my 98 LS1 with 80k miles on it and the viscosity is probably similar.

With the large number of quality oils from which to choose, it wouldn't be a bad thing to choose an oil more to your liking. Visit the thread discussing "Which Oils are Thick or Thin" and have a look at the chart showing the variety and relative viscosities.

My morning piston slap and valvetrain noise has quieted significantly since doing the ARX thing and switching to oils less thick. It may come back when the weather gets colder, but for now it's practically gone.