In accordance with the latest regulations, the 4.0-litre V8 P66 engine of last year has been done away with and instead a more powerful and fuel efficient 2.0-litre turbocharged P48 inline four-cylinder mill (with direct injection) now resides, which will allow it reach speeds of up to 300kph.
To release the power is a redesigned and shortened exhaust system and only a single pipe can only peek out on the right side underside of the car, towards the centre of the door and next to the vents. The second exhaust pipe on the left side of the car has been done away with.
Also, the mandatory weight of the new M4 DTM, when empty, is now less than 1,000kg, but must weight a minimum of 981kg without driver or fuel - this is 50kg less than last season.
This combination of more engine power and less weight means that the M4 DTM has a significantly lower weight to power ratio of 1.6 kg:1hp and should ensure that the car will be able to reach the 300kph mark along the fastest sections of the track on the DTM calendar that includes the Parabolica at the Hockenheimring.
With the new Class 1 regulations stating that there will no long be a need for a number plate, it has allows the M4 DTM's radiator grille to be optimised and the size of the intakes and cooling system to be increased - this includes the bonnet for the intercooler of the 2.0-litre turbocharged engine.
To make the M4 DTM more robust when engaging in wheel-to-wheel battles, the protrusion of the front splitter has been reduced by 90mm, while the rear diffuser has been lowered by 30mm and the start of the diffuser ramp has been moved back by 870mm.
At the rear, the M4 DTM's rear wing (as one section) has been significantly widened by 520mm - an adoption from the Japanese Super GT Championship, and still has Drag Reduction System (DRS), in the form of a pneumatic flap mechanism to reduce the amount of aerodynamic drag generated by the car.
The DRS function will be used with the newly-introduced push-to-pass function that starts this season that will allow drivers to call upon 30PS of extra engine power at the push of a button which will temporarily allow more fuel to be injected into the P48's turbo engine.
Inside, the cockpit receives a new firewall for added safety while doing away with the interior mirror and instead equipped with a rear-view camera and display.
Also, a new vent on the rear windscreen has been added to aid in cabin ventilation, but other than those mentioned, the race car's aerodynamics have remain unchanged against its predecessor in order to avoid an 'aerodynamics arms race' between manufacturers.
The Class 1 technical regulations were announced at the Norisring in June, 2018, by DTM boss Gerhard Berger and his SUPER GT counterpart Masaaki Bandoh that comes with a 'common parts' concept to help reduce real costs, while adding the aspects of greater safety and equal opportunity.
Components for nearly all areas of the car have been standardised and will be produced and distributed in both Europe and Japan to help bring costs down - allowing manufacturers the omit the need to invest heavily into design and development efforts.
However, the biggest difference concerning power plants in the new regulations was the change from last year's 4.0-litre V8s to the current 2.0-litre turbocharged four-cylinder engines that will produce somewhere around the 620hp mark - roughly 100hp more than before.
With the added power, the regulations will allow for the front aero design to be adapted in order to provide more cooling function for the engine and brakes, while the front and rear diffuser as well as the rear wing can be modified to the same standard as the current Super GT specifications.
This season (2019) will most likely see two racing series go head-to-head against each other.