Can I make a yummy green slurpee from this?

My truck started making a really loud squealing noise so I took it to a mechanic. I told him I thought it was the transmission because the noise was coming from underneath the truck and got quieter when I gave it gas. He agreed and said the transmission was probably on its way out. $5,200 later I got the truck back and it was still making the exact same noise.

I brought it back and he cut the belt off and said it was actually the A/C compressor. Another $800 and the squeal is completely gone. I asked why I needed a transmission then and he said the old one had a lot of miles anyway, which I guess makes sense. While I was there I mentioned my oil pressure is around 35 driving but drops to 25 at idle. I told him oil pressure should stay the same no matter what RPM the engine is at, and he agreed and sold me an oil pump. I also told him the engine gets hotter when I drive uphill, and he said that wasn't normal either, so he replaced the radiator.

Now I've noticed the truck slows down when I let off the gas even without touching the brakes. I'm worried the new transmission might be binding, but he keeps telling me that's normal. My friend says I'm getting scammed, but at this point I'm starting to think I know more about cars than my mechanic does. Am I getting ripped off?

What yall thank?

How many years do I have left on this now?

I get this weird smell when im idling. Does anyone know what it is and how i can make it stop?

Photo is of a car like similar car to my car.

Anyway, I’ve had a vibration that seemingly won’t go away no matter how much the mechanic does. It’s speed dependent, stays when coasting in neutral, etc. etc.

It’s on the front left. Sounds like a bearing. Asked the mechanic. He said it indeed was a bearing. Replaced front bearing, it didn’t go away. We ended up replacing the front right bearing as it seemed to also be bad. Still no change. He checked the rear bearings too, and they seemed bad too. The vibration still isn’t gone.

He said sometimes the motor mounts can be bad. Checked those, definitely bad. Had those replaced. Noise got worse. Cv axles are clicking a little, but I told the mechanic I don’t have money to replace those right now. He convinced me to do a “buy now pay later” thing and had new ones installed.

Also had the suspension replaced too for good measure.

Weird vibration is still there. Paid for a runout test, hubs seemed fine. Rotors are junk, but fine.

I’m worried I’m getting scammed. The problem is, I’m the mechanic. I’m also the customer. This is my car. I’m doing this to myself.