Alernator and Idler replacement

I didn't want to jump on someone elses thread and hi-jack it. So I am starting my own.
My alternator just took a dump today. I plan on getting a remanufactured 130 amp one from O'Reillys. I have the 4.0L.
Here are my questions:
1) How hard is it to loosen the belt tensioner? I tried and it just felt stuck. Is it better to get at it from below with a breaker bar?
2) I want to replace my idler and belt tensioner. What is a good source for these? I found them on eBay and Amazon for a decent price. They show the tensioner as being a genuine Toyota OEM part.
3) Before I do any of this, I want your opinions on something. There has been a howling noise coming from my engine bay. I notice it more on the alternator side. So I am assuming it's the alternator that has died and not the battery. Could the howling be my idler or tensioner?

 

it is not very hard. It is easiest having two people. One to lever/loosen the tensioner, and one to pop the belt off the alternator. I just did this with my cousin last week, from the top, and it took 30 mins total. I also had a whining noise, and it was one of the idlers, which the dealer replaced. If you replace the alternator and the noise is still there, I bet it is an idler. As most everyone stated on my alternator thread, the part store ones are unreliable. The oem alternator is a denso. I got mine from rockauto. It seems the general advice on here is anything engine bay related should be oem parts only.

 

Does the amperage matter? Mine didn't come with the tow package, so I have the 100 amp alternator. But I would like to add a tow "package" and upgrade to the 130 amp alternator. Is there any problems that could arise from that? Maybe mess the computer up or something like that?

 

I'm not sure, but I think I have read on here that it is safe, and is merely an upgrade. I'm sure someone else will answer.

 

From what I understand, replacing the entire tensioner is a real PITA. It's much easier to get a new pulley for the tensioner. I got a Febest brand pulley and put in quality Japanese bearings into it. Works like a champ.

It's 100x easier to work on the idlers and belt from the bottom of the truck. Take off the skid plate and suddenly there's tons of room to work. Way too cramped from the top for me.

https://www.tacomaworld.com/threads...arings-in-the-idler-tensioner-pulleys.480961/

 

I just changed the idler, too much trouble to change the whole bracket. Gates has the whole kit. Just spin the idlers with the belt off and change the bad ones. Two of mine were bad but I changed them all, how I have two spares. The tension idler is LEFT handed threads. The alt will slide out the drivers side wheel well, just pull the flap out. Tie a piece of rope so you dont drop it on the ground. Pull the battery and battery tray and work from the bottom. Make sure the serpentine belt is in all the grooves. Mount the lower alt bolt first.

 

Thank you everyone for all the tips.
I'm hoping to get this done this weekend. If I can get the parts in time.

 

Well, I changed out my alternator on Sunday. Easier than I thought. All my idlers seemed to spin fine. No more noise. The bearings in the alternator were going out and it wasn't charging anymore. I got the Denso 210-0572 from Napa. Not a bad price and I got a discount because I have AAA.