Here is a physics mod, which was made for personal use some time ago.

It aims to increase realism and difficulty of trucking.

Mod is suitable for keyboard/gamepad/steering wheel drivers.

About mod ver. 1.4 and its structure
Mod aimed at the players, who want more difficult and life like physics in ETS2. It adds lots of changes to almost parameters, related to truck and driver behavior.
This version contains major changes, compared to previous 1.3 version. To start with, it now goes back to traditional (for this mod) system of custom chassis files.
Also, there is no more soft and normal versions, there is one, "suitable for all" version.

Features list for actual version 1.4
1.Corrected to more real life values such parameters as: max. brake temperature, brakes heating/cooling rates and cabin mass;
2.More realistic fifth wheel: added fifth wheel roll angle;
3.Changed brake efficiency: less overall effectiveness and less effectiveness at low speed (but higher upper margin of "low speed"). Increased max. brakes temperature, increased warm up/cool down rates;
4.Decreased retarder effectiveness;
5.Increased chassis suspension travel values for vanilla trucks and trucks from "supported" list;
6.Decreased truck responsitiveness. More feel of a truck mass - less acceleration, harder to brake with and without load, more air and rotational wheel resistance;
7.Increased clutch strength for more realistic clutch-transmission behavior;
8.Decreased tire friction parameters and increased wheel slip factors - brake path now is longer and at some conditions (muddy, wet road etc) you can loose control on truck or experience wheel slip;
9.Reworked cabin and chassis suspension behavior - during various truck maneuvers truck front less static now;
10.Reworked driver behavior - during truck maneuvers, he`s more prone to move front\backward\side to side (but not that much, like in previous mod version);
11.Increased flywheel resistance - RPM drops faster, when not in gear;
12.Decreased engine compression - truck loses speed more quicker, when no throttle is given;
13.Increased transmission resistance - more losses in transmission.

¡Supported trucks! (for newest ver. 1.4)
Mod support all trucks, but full support (which means custom chassis files) available for this trucks:
DAF XF by 50k, Volvo FH Classic and FH16 2013 by Ohaha, SISU and all Scanias from RJL, Volvo VNL 670 and 780, MAN TGX Euro6 and TGA by Madster, Scania 143 by Ekualizer and Iveco Strator by Shoofer/EM Group, Scania P/G by GT-Mike, Kenworth T800/W900, Freightliner Classic XL/Argosy, Mack Superliner, Freightliner FLB by odd_fellow, Kirilloid22, Dmitry68, Gosha Motor; Mack Titan by Андрей Васильев, vitalik062, Kriechbaum, FRANK_WOT; MB Antos by DANZ; Scania R730 by Bogdan Kasalap; Scania 4 by satan19990, NewTon, Mr.Poland/Chudy/Wojtas, Anaheim i EDD123; Peterbilt 387 by Ch_Vitalik, Kirilloid22, Dmitry68, Gosha Motor; Peterbilt 389 by Viper2 MAZ 5432, KAMAZ 53212, Ural 43202.
To use this mod with these modded trucks, install it with higher priority!!!
If you have some other not listed above truck mods, try to install them with higher priority, than this physics mod, to avoid possible problems.

Credits
AlexeyP. Also, big thanks to SCS, 50keda, Ohaha, RJL, Martinezio, MADster, Ekualizer, Shoofer and EM Group, dmitry68, Softlab_NSK, Oleg Conte, Sergej Baltazar, Bruieser, Jawa, Stalker45, Mr.Nick, M@x_1996, RTA, slava1, odd_fellow, Kirilloid22, Dmitry68, Gosha Motor, Андрей Васильев, vitalik062, Kriechbaum, FRANK_WOT, DANZ, Bogdan Kasalap, satan19990, NewTon, Mr.Poland, Chudy, Wojtas, Anaheim, EDD123, Viper2 and all other mod truck makers, whose trucks were represented in 1.0-1.2 and 1.4 versions of this mod! Also, credits to natvander for his tips and hints!

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