At Tennocon 2018's Sounds of the System panel, it was mentioned that lines of dialog in the Grineer language are generated via inputting an English text string into a script. Whether the output is later edited was not mentioned, but it's quite clear that, much like the Corpus language, Grineer is largely based on simple letter substitution rather than intensive more conlanging strategies.

Based off of previous work on both the wiki and youtube , I've managed to figure out a fairly consistent rubric for basic letter substitutions that make up the bulk of the Grineer 'language'. Some rules aren't consistently applied, or may have been valid for lines recorded at one time, but not others.

English Grineer Example/Notes
B BR, K, R Brogrer ("bored"), Kerhur ("behind"), Raf ("back")

Not applied consistently, may be vowel-dependent

C K Onke ("once")
CK F Kref ("check")
D R Spotter ("spotted")
H R Rey ("hey")
I U, HU Hu'm ("I'm")
L- D- Dof ("lock")
LL SS Khuss ("kill")
P G Gregort ("report")

Not applied consistently

R-, -R- GR Regrer ("here")
ST TR Retrroy ("destroy")
TH KL Klem ("them")
W R Rusr ("wish")
WH- GR- Grat ("what")
CL- GR- Grear ("clear")

Some words are irregular, or the substitutions used are not immediately apparent. Examples include "gar" ("you") and "tu" ("my"). 

There is a high degree of variation between grineer voices, essentially because the lines are all being delivered by employees of DE or hired voice actors who have had only a minimum of coaching. They are attempting to sound convincingly 'foreign', working with a text that contains consonant clusters they are not familiar with. This leads to different choices by each voice actor.

This is evident in the Grineer quotes page, where Grineer Male A occasionally adds extra vowel sounds to words, Grineer Male B slurs extensively and Grineer Female occasionally uses English pronunciation for vowels that is not heard in the other two. Each person is attempting to read the script phonetically, and assigning different values to vowels and consonant clusters. This becomes especially noticable in words like "mhunr" ("mind"), in which the three voices variously pronounce it "mohuner", "munur", and "munre". At present, the quote page text renders the Grineer text as "mohner", demonstrating how difficult it can be to work just from transliteration of inconsistent pronunciation. 

Due to these inconsistencies and limited voice samples, some sounds are heard in only a few sound files and can't yet be parsed. "SH" only shows up in two Kuva Guardian quotes, for example. There are also some possible changes that have been made to the substitution rules over time. Most of the dialog from the beginning of Vor's Prize doesn't appear to be fully compatible with the rest, especially due to an extra substiution: O -> K. (ex. Vor pronounces "go" as "gkk"). This appears to have been dropped, due to how cumbersome the rule would have been to stick with. The Kuva Guardians also appear to have dropped a rule: P -> K is not evident in their dialog, creating words like "plake" ("place"). Some rules appear to have always been inconsistent: It's not clear why "P" was allowed in "spotter" but not "grekort". One "B" becomes "BR" and another becomes "K", and no clear logic why has been established.

It is likely that these rules continue to evolve over time, that more are already in effect but have yet to be parsed from dialog, or DE could just decide to go in a complete different direction. For now, this is my working document for figuring out Grineer-language dialog.


All taken from the Grineer/Quotes page.

Grineer English
Agrea krear. Area clear.
Okay, okay, hu'ss kref. Okay, okay, I'll check.
Am hu seehung klhungs? Am I seeing things?
Ass grear un klos sektor. All clear in this sector.
No aktuvuty to gregort. No activity to report.
Hut's too kuhuet un reger. It's too quiet in here.
Rey, deave tu mukler out of klhus. Hey, leave my mother out of this.
Hu'm broger out of tu mohner. I'm bored out of my mind.
Gar guys see anyklhung suspukhus? You guys see anything suspicious?
Jutr unke, hu resor hut roudr get exkhutung around reger. Just for once, I wish it would get exciting around here.
Ror rhur get truf rhukl klhus gotr? Sekhuruty aghuntr grat? How did I get stuck with this post? Security against what?