2005 GTO LS2 Engine Oil Pressure
 

Hello. I'm new to this forum and new to forums in general. I have a question regarding engine oil pressure on my 2005 GTO. Hope this is the right place to post this question. If this isn't the right place, please redirect me. Here's the question: What are normal, good oil pressures for my LS2 at the following rpm levels: 750, 1,500, 2,000, 3,000 and 4,000. The car has 122,000 miles and is a 6-speed. I recently had some major engine work done following an SLP oil pump failure and following the work my oil pressure readings have been lower than prior to the work. Car runs fine but the lower readouts are a bit scary. Today I replaced the 5w-30 Royal Purple with 10w-40 Mobil 1. Pressure is now running about 40 psi in 6th gear at 2,000 rpm. My local GM dealer checked his computer and it listed the "minimum" pressure for 2,000 rpm to be 18 psi. It did not list normal or maximum pressures. Just want to make sure I'm not putting too much stress on the engine with the heavier oil. Thanks, in advance, for your input.

Go to ls1gto. They like the new GTOs much better there, than here. All the tech about GTOs you'll ever need. I love my LS2GTO, but don't even bother to discuss it on this board anymore.

Rule of thumb is minimum of 10 lbs of oil pressure per 1000 RPM and you should be fine since yours is twice that. 10W-40 should not cause you any problems.

Back 40 + years ago straight 40W was what was used in many high performance engines and it's much thicker than 10W-40 is. Not something you want to run under 40 degrees ambient though.

The owner of PY wants to welcome all Pontiacs to this site, so welcome and if I can help you with any questions I'd be happy to.

Thanks for taking time to respond to my question. I just want to make sure that when I get into the higher rpm ranges (4k to 6k) the heavier oil won't create too much internal pressure on gaskets, etc.

Feel free to post in the 04-06 GTO tech section. Some guys aren't as welcoming to the late models but we have a good gathering here where you won't be ridiculed or laughed at.

On my 04 LS1 it generally runs 30s to mid 40s psi through the ranges. Never seen it drop to 18 for sure even warmed and running mobil 1. Maybe high 20s 100 degree summer day all wormed up after freeway driving for awhile.

In fact I used 20 PSI for the red light on my Aeroforce gauges and it has never lit up.