1994 Chevy S10

Hi, I have a 1994 Chevy S10 truck. I been having some problems with it.
I was having transmission issues with it (I posted on that one before) , but now it has started leaking oil and I would like to know why.
The color of the oil in the oil leak is dark brown and oil gauge is giving me odd readings.
For example, when I start the truck the oil gauge says it is half full (40), but it warms up and I am in stop and go traffic it drops to 20. But, If I step on the gas the reading goes back to 40 again for a while and then drops back down again.
I thinking about just getting a different truck because this one is becoming a pain to fix, but I would still like to know what could be wrong with it.
Does anyone have any suggestions?

First off that oil gauge isn’t an idicator of how much oil is in the motor it’s the oil pressure gauge and tells you the approximate oil pressure. Dark brown oil often indicates its been contaminated with coolant which most likely means a leaky head gasket. Good luck

Mike

If you have a 4.3L engine and the leak is at the rear of the engine it is highly possible that the sensor that works your gauge is leaking and not operating correctly. It is a somewhat cheap and simple repair it that is the problem. And get an oil and filter change.

@Kitty239 an engine will not have the same oil pressure at all times. It sounds like the oil pressure may be within normal parameters.

Since it’s concerning you, consider having a mechanic hook up a mechanical oil pressure gauge to confirm that all is well.
And have him diagnose that oil leak also.