Can I go from 5W30 to 10W30? 2007 Silverado C3500

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It has the 6.0L with 205K miles. I'm thinking the oil pressure is on the low side and thought this might help some, at least before replacing the oil pump. Posted these on a Chevy truck forum and the consensus was not to worry about it.

When I first start it cold (70F) it shows just under 40. And I could swear just 15-20,000 miles ago these numbers were 5-10 psi higher. I put in a new sender just to be sure and checked the pressure with a manual gauge.

idle
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cruise
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downshift
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How is the pressure when warm? (the temp gauge isn't shown in any of your photos)

Also, I notice there is no red zone in the low range. The last time I drove a car with an oil pressure gauge (was actually an older GM car, a 3rd gen F-body), there was a red zone at the low pressure numbers. The manual said something like "normal pressure is around 20-60 psi, but anything above the red is acceptable"
 
A 10w30 will not be thicker at temp than 5w30. In fact, it may be a tad thinner.

Try a 40 weight like Mobil 1 0w40 or Rotella 5w40.
 
Originally Posted By: dlundblad
A 10w30 will not be thicker at temp than 5w30. In fact, it may be a tad thinner.

Try a 40 weight like Mobil 1 0w40 or Rotella 5w40.


This. Unless you go with Mobil 1 High Mileage 10W30 which has a 3.5 HT/HS.
 
Originally Posted By: dlundblad
A 10w30 will not be thicker at temp than 5w30. In fact, it may be a tad thinner.

Try a 40 weight like Mobil 1 0w40 or Rotella 5w40.


+1 or Castrol 0w40, all will work well in this engine year round.
 
I went to Castrol HM 10W40 in my 98 K3500 with the 454 from 5W30 and got higher oil pressures. Truck seems to run the same.
 
Your oil pressure looks fine by me. Most engines run about 10 to 20psi at hot idle and between 40 and 60psi at high rpm. If in doubt, put a REAL oil pressure guage on and re-check.

Ooops! You did do the manual guage...
 
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OK, time for an oil change anyway and thought I'd experiment. Normally it wouldn't bother me but because it was higher across the board not long ago, it does a bit.
 
My 5.3 had the same issue. Could not get over 40 lbs in passing gear (3rd gear out of 4). Oil filters were plugged with carbon. LB valve cover near the pcv was carboned up bad. Cleaned valve cover and replaced the oil filter and oil pressure back to normal (around 45psi cruising)
 
Looks fine. pump is to put the oil where it belongs not to "float" anything with pressure.

AN A3/B4 ACEA 10w30 should hold up better to heat. Look for that on a good oil.

I run a 10w30 QSUD NON DEXOS in my rogue 2.5 Spring thru Fall and it's great.
 
Originally Posted By: classic70
My 5.3 had the same issue. Could not get over 40 lbs in passing gear (3rd gear out of 4). Oil filters were plugged with carbon. LB valve cover near the pcv was carboned up bad. Cleaned valve cover and replaced the oil filter and oil pressure back to normal (around 45psi cruising)


I would have loved to see some pics!
 
In a motor with all internals still in spec 20psi idling wont hurt. Pressure is your engines friend especially on one with high mileage. reason being that 1 loose fit worn bearing will drop more pressure than it should possibly causing additional wear. also low pressure can also be mirrored into any parallel oil passages causing other issues.
 
I'd say it increased slightly. Maybe 2-3 psi across the board. Better than nothing but not as much as I had hoped. Just psychological but like to see the needle to the right of center when cruising.
 
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