After I replaced my oil pump and switch the oil gauge is showing pressure around the 3/4 mark. What's causing this?

 

You now have good oil pressure that the old worn out oil pump wasn't delivering, most likely.

 

My old started at 60psi that was low?

 

It's staying around the 3/4 mark and half way between that mark and 120

 

Oh, the V6 gauge is different from V8 models eh? Thought you had the (V8 style) 80 psi gauge.
No 60 isn't low. Considering the gauge model differences, I'd make sure you have the right pressure switch.

 

I got the one from auto zone part number ps240

 

The 3.8L engine uses a high pressure system that runs about 60PSI, so anything from 50-70 you should be happy. More or less and you could start seeing problems. Too low and you dont have enough oil to pump up the lifters and get oil to the top of the engine, or not enough to keep a layer on the bearings. Too much and you will put too much oil in the lifters which messes with how your valves work and it can also send more oil to the top of the engine than can drain back which will cause you to starve the engine of oil.

The LS1 likes oil pressure to be about 40PSI so a few above and below will be good. Same problems as discribed above for too much and too little.

Massey

 

Without looking it up, I'm going to presume you got the correct box. But how do you know some dimwit there didn't at some point in time switch the switches? Not that that's ever happened before!!!

 

I'm not sure. Ill probably get a different switch from napa or advanced and see what happens. I did change the oil pump if that makes a difference.

 

Even a new oil pump is only going to produce the amount of pressure it was designed for. The 3.8L engine has a piston/spring type pressure relief valve that is behind the oil filter adaptor, and it needs to be able to move easily to prevent and over pressure condition.

Oh and I work at O'Reilly Auto and we get from time to time a mis-boxed part. Another thing to look at is the part itself. My BWD products are great but my Master Pro... Well lets just say in 95% of the times it is better to spend a couple extra $$$ for the BWD parts.

Massey