This is the climax of the film where Cruella and the Baduns attempt to stop the truck carrying the dogs back to London.
While it is an exciting sequence, what strikes me is how little the dogs have to do. They have been active characters before this - searching, fighting and avoiding capture - but there's nothing left for them to do. Except for Perdy catching a pup by the tail as the truck tilts dangerously, the dogs are literally just along for the ride. While the audience has been asked to identify with the dogs as protagonists, now the audience is stuck rooting for a truck driver who has no history with the audience and no idea what's really going on. It's a bit of an odd turn for the film to take.
It's also something of a disappointment that the bad guys are the authors of their own misfortune. Again, after the dogs have worked so hard to rescue the puppies and return home, why not give them the opportunity of striking the final blow? Instead, the bad guys cancel each other out and the dogs ride home to safety.
There are some interesting shots where the backgrounds recede behind the characters riding in vehicles. If they were done as traveling mattes, the matte work is excellent as there are no matte lines visible. Those lines are visible in later films like The Rescuers, so why are the shots here better? Perhaps they were done using the multiplane camera, which would not require matte work as the entire shot would be done in camera. Does anyone know?
This part of the film really belongs to Cruella. While her henchman have done most of the dirty work until now, she is the main villain in the chase. In shot 158, her car crashes through some trees and parts of it get stripped off, the resulting look in shot 160.1 is very much a nod to the California hot rod culture of the 1950s. Big Daddy Roth, anyone?
Prior to those shots, in 149-154, the car lands in a snowbank and instead of animating the snow, someone decided to use the live action footage from the model shoot of the car. The live action images were transferred directly to cels and painted. As a viewer, these shots have always called attention to themselves and taken me out of the story momentarily. For one thing, the texture of the snow in these shots doesn't match any snow in the rest of the film. For another thing, there are registration problems. You can clearly see the live element weaving relative to the painted backgrounds they've been inserted into.
The film leaves Cruella, Horace and Jasper stuck in the snow without a way home. Are the arrested? Horace and Jasper are guilty of burglary. Cruella is guilty of attempted murder of a truck driver. Are they fined? There's no doubt that Cruella has broken the speed limit and driven recklessly. We'll never know.