This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Indiana Jones and the Last Crusade
The bit where it seems that Indy has gone over the cliff in the tank, and his father and friends are staring over the side of the cliff, stricken. And then Indy appears beside them, battered but alive, looking over the cliff in confusion to see what they're all looking at. And then — the truly tear-jerking bit — Indy's father embraces him in a bear hug for the first time ever and chokes out "I thought I'd lost you, boy!"
Henry immediately filled with regret after thinking his son has died:
Oh, God. I've lost him, Marcus. And I never told him anything. I just wasn't ready, Marcus. Five minutes would have been enough.
It's made even sadder in the Junior Novel and Adult Novelization, where Henry realizes that he was so obsessed with the Grail, he was never a good father at all and never even told his son that he loved him.
When Henry's shot by the Nazis and Indy falls to his knees, frantically trying to stem the bleeding, his hands trembling ... it's devastating to see that sarcastic bastard so shaken.
After all the bickering they engaged in, both dramatic and comical, seeing Indiana Jones actually shedding tears when his father was shot is proof that he did still love and respect him.
This troper has grown up with this movie, and this scene has lost none of its shock value. You know it's coming, you tell yourself it's all special effects, but it still gets you anyway.
On a Meta level, seeing Sean Freaking Connery on the ground, bleeding and obviously afraid and in pain. Seeing one of the Baddest of Badasses in such a vulnerable state...it starts to drive home a sense that Anyone Can Die at this point in the game.
Elsa's death due to her inability to let the Grail go, and Indy's near-death for the same reason until his father intervenes.
"Indiana... Indiana... let it go."
The scene at the crossroads, where the argument between the Jones' about which direction to go gradually takes on more personal tones as old wounds are brought up for what, it's implied, is the first time.
Henry Jones: The quest for the grail is not archeology, it's a race against evil! If it is captured by the Nazis the armies of darkness will march all over the face of the earth. Do you understand me? Indiana Jones: This is an obsession, Dad! I've never understood it. Never! [Bitterly] And neither did Mom. Henry Jones:[Deeply hurt] Oh yes she did. Only too well. Unfortunately, she kept her illness from me and all I could do was mourn her.
Can I nominate the above for a Fridge Brilliance nod? "The scene at the crossroads." Perfect description for father and son's relationship at that point, innit?
Just before the temple collapses, Henry and Indy see The Knight one last time. Henry looks upon The Knight with awe and respect, while The Knight waves them goodbye, knowing his duty is done and he's going to die. Finally.
It's a small moment, but the look on Elsa's face when she's watching the books being burned is devastating. She looks like she lost one of her best friends.