@techoflash7643 Awesome!  I'm glad to hear you got it up and running!  If you enjoy that mod truck you should search this site for the Freightliner Coronado,  Freightliner Classic XL, Peterbilt 389 Glider, Kenworth W900 Highway Killer and Peterbilt 362.  All of those trucks are made by the same guy who made that Peterbilt 579 except they have way more customization options than the 579 does.   If you see multiple versions of any of those mods always grab the ones uploaded by Mods82.  His mods are always the most current ones available.

@Truth Be Told  OMG YOU ARE A TRUE LIFE SAVER THANK YOU SO MUCH THIS HELPED SO MUCH OMGG

@techoflash7643 Here's the deal-   This version of the mod is missing 2 files that it needs in order to work properly. Those files are "Engine Sounds.scs" and "Pete 579 Personal KEY.scs".  You can get those by looking near the top of this page and clicking on the tab that says "Files".   This will show you a history of the previous versions of this mod that he has uploaded here.  Download any of those older versions, open the file and take out ONLY the Engine Sounds.scs and Pete 579 Personal KEY.scs files and drop them in your games Mod folder along with the contents from this most current version of the mod that you have already placed there.   This should give you all of the files from the most recent version of this mod PLUS the two missing ones that you grabbed from an older version.   Now run the game and go to the mods menu.  From here you will need to activate all of the different parts of the mod in the correct order.   Here is a list of all the mods parts as they should be arranged in the games mod screen, starting from the top and moving downward. TOP----  Engine Sounds, Pete 579 NG DLC Accessories Compatibility, Pete 579 NG SISL Pack Compatibility, SiSL's Mega Pack, Pete 579 NG DLC Steering Wheels Compatibility, Pete 579 NG, Pete 579 NG Personal Key, Trucks & Trailers Flarepack, Trucks & Trailers Wheels.----BOTTOMThe file names that I've written in BOLD letters are MANDATORY in order for this mod to run.  The other files are optional as they simply enable the truck to use extra content like the DLC steering wheels and interior accessories if you have purchased them or the various decorative items from SiSL's Mega Pack if you have downloaded it.  Hope this helps.  I'll check in a bit later and see how things are coming along for you.   Good Luck!

@mods82 I believe he's having an issue because this most recent version of the mod you uploaded did not include the engine sounds file or the personal key.  It didn't have the real logos file either (Not that it matters). With the exception of those three files everything else was included and works just fine when used with a key from one of your previous versions of the mod.   

@techoflash7643 Inside the rar file are scs files, you need to unzip the rar file, it is an archive, for this you need the program Winrar or 7zip, the latter is free.

@Arturo Find the cause of the conflict, disable other tuning mods or trucks one by one.

@mods82  hello im doing the same thing my game closes what should i do.

@techoflash7643 Download the archive Peterbilt_579_Nextgen_ATS_1.55.rar extract the files from it and connect them as shown in the screenshot inside the archive.

@mods82  I tried what you told me but it doesn't show up in the mod selector, i've tried deleting it off my computer and re-downloading and nothing, please make this work i love this build and really want it to work, also the other mods work its just the personal key and truck file that say wrong format or damaged, get back to me when u can

@techoflash7643 No need to unpack the scs files of the truck and key, move them to the mod folder and connect.

@EverShadow  Are you certain you actually turned the headlights on?   If you hit the headlight button once it turns on the lights on the dashboard but that's it.   You need to hit the button a second time to turn the low beams on.   If you are already doing that correctly and still not getting results then you need to take a look at the load order of your mods.   Do not activate the Open Def mod unless you made some sort of change that requires it to be active.  Here's a list to show you the proper order to have your mods stacked going from top to bottom.  (Mods marked with * are mandatory)-----TOP-----Real Logos*Engine Sounds*DLC AccessoriesSISL CompatibilitySISL Mega PackDLC Steering Wheel Compatibility*Peterbilt 579 truck mod**Peterbilt 579 Personal Key**Trucks and Trailers Flarepack**Trucks and Trailer Wheels*-----Bottom-----Hope this helps.  Best of luck to you.

@DUDE  He been busy man , real busy......

@Metal Knights Jon Ruda is a really good mod creator. A bit pricey, but Jeff Favignano has several mods from Ruda and he's not disappointed.