Ran my oil too long now low pressure


Asked by TDBroke Feb 18, 2020 at 10:53 AM about the 2008 GMC Sierra 1500 SLE1 Crew Cab

Question type: Maintenance & Repair

Generally I'm very methodical about maintaining my 2008 GMC Sierra 5.3L
but I changed to Mobil 1 synthetic and was told I could get a little more
mileage between changes. So I did. And that was a mistake. I checked the
oil and it was extremely low. Low enough that I had to add 2 quarts. Now my
idle pressure is about 20 and my running pressure is about 38 or 39 when
it's normally around 40 to 41. I changed my sending unit about 8 months
ago. I have a Wix filter on it now (just changed the oil) so everything is in
line. But I'm getting 41 at cold start idle and then it will drop down to 20 at
idle after hot and 38 or 39 when running at 65 mph. Did I mess this up
somehow? What are my next options?

4 Answers

Just because you can run synthetic longer does not mean you don't need to check the oil level. A this point all you can do is keep running the engine for as long as it will run.


Strangely enough today I'm getting the correct pressures. I don't quite understand what's happening with this thing.

Your Answer:

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