So I have an 08 Tahoe with right around 200k on it. When It gets cool (40's at night) it tends to startup at the 26-28 psi range. I know this is good for 3k-4k rpm it just seems odd its that low when colder. After a 3-4 mile cruise to work its in the 30psi range cruising at 30mph or so and will get up to 40 if I take off hardish and get to around 3k rpm. I had the oil sending unit replaced less than a year ago. The oil gauge doesn't act funny like it did when the unit went out. Should I look at switching oil viscosity? Or should I just accept that its going to be low rpm until it gets warmed up? Driving down the interstate at 75 she runs around 42-44psi which is what its done since ive had it at 100k miles. Maybe my oil went bad prematurely? Im going to try and get an oil change done this weekend so just checking if I should switch from 5w-30 or not.
Low Oil pressure when cold 2008 Tahoe
- Thread starter AP90
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5W30 is fine unless you are in a super cold or extremely hot climate.
Make sure you use quality synthetic oil - dexos approved and
a quality oil filter like an acdelco or wix
If you've waited too long, the oil may have a lot of moisture or contaminants in it
40 ish cruising warmed up engine is very normal
Make sure you use quality synthetic oil - dexos approved and
a quality oil filter like an acdelco or wix
If you've waited too long, the oil may have a lot of moisture or contaminants in it
40 ish cruising warmed up engine is very normal
Short trips can cause some moisture to creep in there with the oil. The 5w-30 should be just fine in 40 degree weather. Colder, may want to go to 0w-30 but you are a ways from that threshold. IMO, the readings you are seeing seem normal. What brand oil sender switch did you use and was there a filter in that line and if so, did you change it?
donjetman
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Doesn't sound right to me. Maybe a bad sender, or clogged screen, or teflon tape when sender was replaced blocking its hole?
Over the yrs, I've run 5w-30, 5w-40, and 0w-20. At first startup, winter or summer, it has always gone immediately up to 50-55 psi. Hot idles at about 20psi and cruises at 30-35psi.
Over the yrs, I've run 5w-30, 5w-40, and 0w-20. At first startup, winter or summer, it has always gone immediately up to 50-55 psi. Hot idles at about 20psi and cruises at 30-35psi.
Dustin Jackson
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Could be the oil pressure relief valve in the oil pan sticking in the morning letting oil out? I am not sure how those work.
I also heard that the o-ring being damaged could cause low oil pressure when cold but your oil pressure seems fine when it's warm so not sure..
I also heard that the o-ring being damaged could cause low oil pressure when cold but your oil pressure seems fine when it's warm so not sure..
