Modules are add-ons that can change the way the GDR behaves. There are two types of modules (active and passive) and each GDR can have two modules equipped at a time. Passive meaning "you don't need to physically turn it off and on" and Active meaning "it needs to be assigned to a button that you control".
Absorbent Coating (passive)
The Grinder is covered in a radar-absorbent material that removes your signature from the enemy's radar. This "stealthy" module, however, is only active when your Grinder is standing still, or moving at the speed of "one" on the throttle control.
Works well with Grinders that have a stationary load-out build, such as a Hammer Overhaul or rail-gun sniper loadouts.
Moving faster than "one" in any direction, horizontally or vertically (jets) will turn off the module
Moving at the speed of "one" and then walking down a slope will speed you up enough to deactivate the module.
As long as the Overhaul is hovering in place with the Hummingbird Drive, the module will activate.
-Now you see me, now you don't.
Target Recognition (passive)
Is that a Drill or a Dredge around the corner? With this module you no longer have to guess. Target Recognition replaces the circles on the radar with icons of the type of Grinders nearby, enemy and teammates.
"-I see dead people."
Ram-Air Intake (passive)
This module provides an extra internal cooling fan that activates when moving at a speed faster than a walk—i.e., while jumping horizontally, not vertically.
Don't know which module to load on your Grinder? Ram-air Intake has become the standard go-to Module for its ease of use. You don't have to think about, just load it and go!
Useful on any Grinder, however, it's very important on a Goldrush or Hopper, not so much on a Drill.
Synergizes very well with the Thermal Pump module. Build heat creating fuel, then cool down while jumping to your target.
The faster you move, the quicker your GDR cools.
-Feeling HOT, HOT, HOT!
Safety Override (passive)
The "Last Laugh" module.
Upon ejection, your Grinder will fire every weapon at once, the exception being the Hammer missile.
If you pull the ejection handle yourself the Safety Override will still activate, This makes for some interesting "suicide" maneuvers.
Be careful around Grinders with this module, it will hit enemies and friendlies alike.
As a Grinder is destroyed, it sometimes falls backwards or rolls on the ground, which will cause the weapons to fire in unexpected directions.
Air Brake (active)
Think of this module as an emergency brake for your Grinder. When you manually activate Air Brake, you will come to a complete stop while flying (jumping) horizontally. Great for pilots that like to move fast and overshoot their targets while jumping or tend to crash a lot upon landing.
It's good for racing toward an enemy, then using Air Brake to stop overtop of the target, in their blind spot, and rain fire down on them.
Not very useful on slow, lumbering Grinders like the Dredge or Catalyst.
Besides Air Brake's obivous use of keeping you from crashing, there are two main attack options to start with, stopping in front of an enemy or passing over the target to stop and turn at the target's rear.
-Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.
Power Venting (active)
Power Venting converts remaining fuel into coolant. It's like magic!
Not very useful. It "feels" like a full tank of fuel should cool more than it does.
- UPDATE-- Power Venting has recently seen an increase of use, replacing Coolant Flush on some builds. It appears to a big favorite among Drill pilots to use with the Drill's ability to "drill" the ground for extra fuel.
Can be used with a sniper load out to gain one or two more shots.
-I heat up, I can't cool down. You got spinning 'round and 'round.
Signal Boost (passive)
The different Grinders have varying radar ranges. Basically. the larger the Grinder, the smaller the radar range. Equipping your Grinder with this module will increase the range of it's radar signal.
Good for Dredge. No sneak up on Dredge. Dredge see ram coming. Dredge stronk!
"Hammer" Overhauls tend to be loners on the battlefield, so using this module may help from getting ambushed.
Light and medium Grinders probably won't use this much since they already have healthy radar ranges.
-R2, try and increase the power!
Backup Generator (passive)
Normally when you shut down your Grinder there is not much to do but wait. Backup Generator allows the pilot to continue firing weapons, while shut down, by using the drop-down scope to see the enemy. Remember, while you are shut down, you have increased cooling and are removed from the enemy's radar.
Works very well when paired with Railguns and Hammers.
Keep an eye on your radar, you have limited vision and are vulnerable. Enlist a teammate to keep an eye on you while shut down.
Does NOT work well with Absorbent Coating. I mean, you're already shut down and off the enemy's radar!
Use on a double Railgun Rook to lose friends and make enemies!
Works well with Auxiliary Pump (builds fuel while shutdown) and Signal Boost (so people don't sneak up on you).
-Hey McFly! Those boards don't work on water. Unless you got power!
Coolant Flush (active)
When Coolant Flush is activated, your Grinder will shut down and begin dumping heat at an increased rate. Upon completion, the Grinder will automatically restart. You cannot end this process early. As this method of shutting down actually "disables" the Grinder, you will not be able to use the Backup Generator or Auxiliary Pump modules.
Aside from the ice geysers on Cryptic Tundra, Coolant Flush provides the fastest cooldown.
Watch the module icon when in use to get an estimate of when you will restart.
It can be used during a jump to also escape skyjackers.
- "Shut it down, shut it all down."
Thermal Pump (active)
When active, this module creates fuel by generating heat. A solid, general-purpose module that is good for just about any loadout.
The Thermal Pump and Ram-air Vent combo is a favorite to use by both beginners and veterans.
Don't forget to turn off Thermal Pump or you will shut down.
You don't need to always fill the tank. Practice using it in short bursts to gain just enough fuel for evading attacks.
- "Bring me the fuel. For the glory of Humungus!"
The Grinder will refuel while shutdown. ‘nuf said.
Aux. pump will turn on ANYTIME a Grinder shuts down, whether on purpose or by accident, so use your imagination. The only exception being that Aux. Pump will not activate while Coolant Flush is running.
- "I don't nap. I recharge."