Is there a way to keep all teammates alive through the suicide mission without them all being loyal? Jack is my only disloyal party member and she dies no matter what choices I make.

I got it with Jack not being loyal. Picked Garrus as the Leader both times, Legion in the vent and Samara for the shield.

I lost Jack's loyalty after her fight with Miranda and I still managed to have everyone live. Just don't choose a disloyal party member to lead a team or do any special task, or accompany you to the final boss during the end game

She dies when she is holding the door while I fight the final boss.  Who did you take into the boss fight with you ?

You have to have basically all soldiers holding the line then.  Grunt, Garrus, Zaeed, Legion most likely need to be left to hold the line.

Thanks, I brought Wrex and Miranda with me so I will try bringing Tali and Samara or something.

I brought Miranda and Mordin and was fine.

" @dropbearGSH: They all need to be loyal, no way of getting around that. "

" Thanks, I brought Wrex

Jack will survive holding the door if you take Thane and Miranda with you for the final battle.

" @dropbearGSH said:

" Thanks, I brought Wrex

:O "

Not everyone has to be loyal, but the people you pick to do things must and you need all the important ship upgrades.
 

Yes.

Mordin died on me the first time, so on the second time I took him into the boss battle with me in an attempt to keep him alive. I was afraid he might die during the cutscenes after the final boss (i dont even know if anyone can die like that), but he pulled through. Then I just saved my game and voila. Got everyone. I have all loyalties/upgrades, though.

They do not all need to be loyal, as far as i can tell.
I had 2 unloyal ones; and didn't asign them as anything.
use this stratagy: (just don't use unloyal ones.)

Awesome, I did it! I used Legion in vents, Garrus as the squad leader both times, Samara as the biotic, sent Zaeed back with the crew, and took Tali and Samara into the last boss fight.  Again, Jack was my only non loyal character, but she survived holding the door and now I've got my ME2 S rank. 

Here is my advice.
 

" You have to have basically all soldiers holding the line then.  Grunt, Garrus, Zaeed, Legion most likely need to be left to hold the line. "

" @Alphiehyr:  How doesn't it makes sense?  If you want to insure everyone survives you need all your soldiers on the line meaning you don't send them off for the escort and you don't bring them with you. "