As always, there is no clear winner in 30k. The easy answer is that every Legion is capable of massed armour and every Legion will do it in slightly different, though not inherently superior, methods. Every Legion would maintain motor pools and so while some may be stereotyped as favouring or limiting their deployments, every single one would at least be capable of the tactic.
All Legions have access to 2 common Rites of War that are based around vehicles.
Armoured Spearhead allows everyone to ride in a Land Raider and additionally provides
Ld penalties against Tank Shocks.
Armoured Breakthrough allows Predator Squadrons as Troops, and additionally moves Sicarans into the Elite slot. All of your lighter vehicles become Fast.
Both of these require that your army is entirely mounted.
As for Legion-specifics:
- Sons of Horus get more reliable Reserves rolls and Reavers can Outflank their Rhino/Land Raiders as needed. Also make wider use of Dreadclaws which may allow for armour saturation.
- Death Guard can make the board a poisonous hellscape of phosphex templates and then drive through without noticing.
- Emperor's Children can deliver an Outflanking hammerblow through their Maru Skara.
- Iron Hands get self-repairing vehicles and can Outflank them with a Rite. They also have the only tank-based Character in the game (Who happens to be absolute nails).
- Iron Warriors can get 4 Heavy Support slots and maximise the number of vehicles on the field.
- Alpha Legion can Infiltrate or Outflank their transports depending on your preferred Tactics. Their special Rite is also based around a Rhino-mounted core.
- Raven Guard can Infiltrate all of their transports. Mor Deythan can further Scout and start the game on top of people.
- Ultramarines can use their tanks to 'mark' enemy units to support the infantry, though not so much as a pure-vehicle force.
- Dark Angels get the Ironwing which offers massive benefits to Predators, mounted infantry and Dreadnoughts.
- Blood Angels get Assault Cannons on *everything*. Enough dakka to make an Ork weep.
- White Scars get bonuses for moving fast. One of the easier ways to achieve this is by driving fast and then dismounting infantry.
In practice, everyone loves a good tank.