engine oil

[omer]

hi.. . I have rebuild my engine and my mechanic says that i should use castrol magnetic oil 5w30.........what i have noticed is when its running for some hours if i check the dip stick for oil level it seems very low and the engine oil pressure indicator comes on and one more thing i am living in saudi arabia and the temperature is around 32 - 45 degree Celsius . so which oil should i use .in winter for 2 -3 months the temp goes around 18-26 celsius

 

[littleblazer]

Well, in the summer months it probably wouldn't hurt to run a 10w30. I am by no means an oil expert but they won't shear as much since the weights are closer together. But 5w30 should be fine. Any brand is fine as well. As for your low level, can you confirm 7 quarts was added when it was changed. Something like 6.6 liters. If that's good I would look into the oil pressure switch maybe flaking out or it could be the oil thinning out due to the high heat. Maybe even a failing oil pump or worn engine. But that shouldn't be the case because it was rebuilt you said? Would you be able to give us a bit more information on year, engine and such?

 

[omer]

i forget to mention, when i check in the morning its ok the level is ok .my mechanic told me to change oil pressure sensor, i baught one from junk yard but didn't replaced yet . the engine was 285000 km on it before rebuilt and i changed new oil pump . its 4.2 l I6 engine in trailblazer ext 2005.

 

[07TrailyLS]

If you check your oil minited after the truck is turned off, you will read low since all your oil still hasn't made it back to the pan. Give it time and try again

 

[Mounce]

5w30 is mostly considered an "all climate" oil. Honestly it doesn't matter what brand or whether it's synthetic or conventional, if you change it when it's due, you should have no issues.

 

[Matt]

If you check your oil minited after the truck is turned off, you will read low since all your oil still hasn't made it back to the pan. Give it time and try again

This. You should really only check your oil level when the engine is cold or a couple of hours after it's been off. As to weight, with your temps only going down to 18°C 10W-30 would be fine.

The oil pressure gauge on the dash is just operated by an on/off switch, basically a dummy gauge that you should only pay attention to if it reads really low or 0. Why they didn't put a real sensor/gauge in there, like the 5.3, I have no idea.

 

[Mooseman]

The oil pressure gauge on the dash is just operated by an on/off switch, basically a dummy gauge that you should only pay attention to if it reads really low or 0. Why they didn't put a real sensor/gauge in there, like the 5.3, I have no idea.

Exactly. The pressure readings are fake and fabricated by the PCM. Only time it tells the truth is when it reads 0, indicating there is no pressure or that the oil pressure switch is defective.

And like what others said. You have to give some time to drain back in the oil pan before reading it.

If you check your owners manual, it gives viscosity recommendations for the temperatures you will encounter.

 

[smt 59]

I recommend Amsoil 5w30 only the best, especially in your climate.

 

[omer]

thank's for all the replies , today i spent too much on the oil pressure sensor i purchased one from scrap yard and it also fluctuates and now i purchased the new one original it works for about some time after 20 minutes it gets to zero and now it works only when i am accelerating and if the car is idle it drops to zero .my mechanic told me that the cable could be the issue ,....is it possible that the oil pump not working properly ? we installed the new oil pump when we rebuild the engine .

 

[omer]

one more thing the engine temperature is good its not increasing

 

[Mooseman]

Could be the wire. Maybe have somebody looking at the dash while you play with the wire. If it drops to 0, it could be the problem.

 

[RTTBLT1]

I had the same issue you are having with the Oil Gauge. When I was driving it was fine but when sitting at idle or while shifting thur gears the Oil Gauge would drop to 0 and go back to normal/40 and it kept doing that over and over. I fixed it but didn't replace anything. I took a compressor and blew out the Male end of the Oil Sensor/Sender electrical connector and haven't had a issue/problem since. It had Oil inside the electrical connector contacts causing the contacts to separate.