Burning oil?

Running a quart low sucks because the pollutants are concentrated in a smaller volume. At least that’s what my shop teacher told me.

 

My thinking as well.

The oil carries away a substantial amount of heat from the moving parts, asking a smaller amount of oil to do the same work means the oil runs hotter which shortens oil life.

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Although I did have a fairly odd fellow tell me once that running low on oil in the winter was better for the engine as it made them warm up quicker.

I allowed him that they probably did...

 

Every week or every other week would give you better data.

The object is to become familiar with the equipment, to know what to expect before pulling the stick - this way changes stand right out immediately.

 

I figured that cleaning the fuel injectors was a little out of nowhere when a mechanic told me they had to be cleaned every 15k miles. I’m not confident enough to change the oil on my Tacoma yet because it’s my only good running truck. I do have a 96 Chevy pickup that I’m practicing maintenance on but will sell later because it’s nothing but a headache for me.

 

Find a new mechanic.
At best he is very under informed, more likely he is taking advantage of your lack of experience - aka: ripping you off.

 

That's baloney.

Relax, don't try to do too much early on, just drive the truck and get used to it. Check the oil level every couple weeks and see if it's going down.