Hello,

My 2007 Tahoe with the 5.3L engine has an issue with oil pressure. It currently has 246,118 miles on it and is experiencing low oil pressure at idle. It can start and run just fine without any strange sounds, and when cold, it makes around 40-50 PSI of oil pressure. However, after it warms up and reaches around 210°F, the oil pressure drops and idles around 0-5 PSI.

I have already replaced the sending unit, but it hasn't solved the problem. I'm considering installing a new pump, but the dealership mentioned that a new pump might not fix it and that there could be other wear and tear. They recommend putting in a new engine. But I'm not paying the dealer's 10K price tag.

I want to try whatever I can to save it as this truck has sentimental value. I'm hoping that using a different type of oil might help. Any suggestions are much appreciated.

 

You've tried the replacement oil sender. I recommend to try a thicker weight oil.

Also realize that at idle there's very little load on the engine, and typically low oil pressure at idle is not a real issue. My 1971 VW has read low oil pressure (at idle when warmed up) for almost 4 decades now.

Is there any way to raise the idle like 200 rpm?

 

How about Lucas oil stabilizer, specifically designed for high mileage vehicles? It might be beneficial, particularly for addressing issues with lifters or the V4/V8 oil pump.

 

My 93 Suburban with 350k miles started this 100k miles ago. Went up to 10-40, then eventually 20-50 to maintain ok pressures. Once warmed up get 10psi idle, 20-30 on the highway.