Low oil pressure (gauge is showing low pressure), small leak...but not losing oil fast or "dumping oil". Knocking noise in the engine. When you look at the engine, there is oil on the drivers side of the engine...also, knocking seems to be on that side. Thoughts? Just bought the truck and I love it...but this has me worried. Hope it's not a "replace the engine" fix! Thank you!

I'm going to simply "spitball" an answer because i don't know WHY you think you need to change the oil pump.

1st, IF the oil pressure gauge isn't showing any pressure, or low pressure, AND there is no engine noises such as knocking or loud tapping, I would suspect a faulty oil pressure sending unit. IF there's a deep knocking sound then an oil pump isn't going to solve the problem. That is UNLESS it turns out to be what I ran across on a 1991 S10 4x4 with a 4.3. There was a "knocking" sound which I traced to the cover plate of the flywheel/flexplate. Turned out to have a cracked flexplate. Changed it and all was good.

I have a 1985 GMC that showed low oil pressure, yet there was no noises coming from the engine to confirm low oil pressure. I changed the pressure sending unit and it fixed the problem of "low oil pressure".

Now IF you're dead set on changing the oil pump, get ready because it isn't a 10 minute job.

You'll more than likely have to at LEAST raise the engine somewhat as (I'm guessing it's 4x4) the oil pan has a deep sump area for the oil pick up. This is so the oil pan can be shallow in the front area to clear the front differential and cross frame area.

Then you get to try to wiggle, twist, wiggle some more, the oil pan out from between the bottom of the engine/crankshaft, and the cross member of the frame AFTER removing all of the bolts that hold the oil pan in place.

IF it were me, I'd be almost inclined to simply pull the engine, at least part way out of the truck, to gain better access to the pan. AND you wouldn't be fighting trying to keep the oil pan gasket in place while doing the wiggle/twist putting the pan back into place.

Hope this helps.

Knocking noise usually indicated low oil, dying with knocking when put in gear usually means NO oil. Check oil level and fill it. If that works you need to check the oil level every day to see if it is leaking and how fast it is leaking.

take it to an accredited service shop that has experience on your make of engine and have a proper diagnosis done and quote
it is possible that there is a spinning main bearing and the test is a oil pressure test using a mechanical gauge
some times it spins , low oil pressure -knocking other times it stops and the oil pressure goes back up , knocking stops
should I be correct , normally it can be repaired in car by removing the sump and replacing that bearing shell, of the shaft is not damaged
i would steer away from a new engine or suggestions of a blown engine but it could be serious

if you ran out of oil and you now can hear knocking sound comming from the engine then it time to get it checked by a mechanic

A comparatively quiet engine is often a worn out engine.( Much of the knocking sound in an engine is caused by compression and expansion of gasses, which in a worn out engine is reduced due to leakage of gasses beyond the piston rings or valves.)

You will first have to have the engine pressure tested on each cylinder to ascertain the overall condition.
Usually there are one of two reasons for a low oil pressure warning light or gauge reading.


No.1: The engine is badly worn and oil pressure can leak beyond the piston rings and into the cylinder.


No.2: The oil pump is close to failing or has already failed.


There is also the slight possibility that both of these faults have occurred at the same time.

The oil pressure light or gauge will show that it has low oil pressure and you shouldn't run the engine that way.

Sounds to me like your oil pump is bad, not pumping sufficient oil at low RPM's. If the gauge shows pressure when driving or revved, the sending unit is working

If your oil pressure light comes on
Don't ignore it. An oil pressure warning light (or low gauge reading) means one of two things: either your engine has dangerously low oil pressure (for a variety of reasons which we'll get to in a minute), or the oil pressure sending unit that triggers the warning light (or operates your gauge) has failed.
The question here is whether you have a serious problem or a minor one.
First, do not keep driving if the oil warning light is on or your oil pressure gauge has dropped. Stop the engine, let it sit for a few minutes, then check the oil level.
Is the level low? If the oil level is down more than two quarts or no oil is showing on the dipstick, adding oil to bring the level back up to the full mark may be all that's necessary to make the light go out. Just keep your fingers crossed that you haven't damaged the engine from running it too low on oil. If you hear rapping or knocking noises the engine starts, you're too late. The damage is done and now you're stuck with the consequences.
Note: On some late model vehicles, the warning light will come on (or a message will appear) if a sensor in the oil pan detects a low oil level. The light is supposed to come on before the level gets low enough to cause any damage.
If your oil level was low, it means your engine is either leaking oil or burning it. Leaks can be fixed by finding and replacing leaky gaskets and seals. Sometimes the oil filter will leak if it isn't installed or tightened properly. But an oil burning problem means the valve guides, rings and/or cylinders are worn or damaged and more costly repairs are needed.
If the dipstick shows a full oil level, then low oil obviously isn't your problem. The oil pressure may be low because of a worn or broken oil pump, a plugged oil pickup screen in the engine's crankcase, possibly a plugged oil filter or excessive bearing wear. Or, the oil pressure may be fine but the oil pressure sending unit has failed. Further diagnosis will be required to determine what's wrong.
Should you attempt to drive your vehicle home or to a service facility?
It's risky. If the problem came on suddenly, your engine does not have a lot of miles on it (less than 60,000) and you noticed no unusual noises (no valvetrain clattering or engine knocking), there's a good chance that all that's wrong is the sending unit. But, there's no way to know for sure without actually checking the engine's oil pressure with a gauge, or replacing the sending unit to see if a new unit makes the light go out. If the problem is only the sending unit, your engine still has oil pressure and you can continue to drive it until the sending unit can be replaced. But, if you're wrong you risk ruining your engine.
If you think you might have a low oil pressure or oil delivery problem because of a bad oil pump or one of the other problems we mentioned, do not drive your vehicle. Doing so only increases the probability of further engine damage. Have the vehicle towed to a service facility for repairs.

The engine is low on oil. but assuming it is not.
The engine is either idling to low .
The engine oil pressure itself is low. The engine oil pressure switch is leaking or not reading the oil pressure in the car.
I assume there is not knocking noise from the engine.
I would check for any oil leaks on the engine .
IF there are no leaks , I would change the oil pressure sesnor or switch first .
This could lead into major engine work.

Good luck

you need to get your viles checked that is the promblem..you may have a rod knocking as well