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NASCAR will have a new look and new technology from the start of the 2022 season at Daytona. The cars will retain a tube frame chassis and silhouette bodies, but the shapes will be different to closer represent the road cars, and almost every aspect under the skin will be new aside from the engine.

The flywheel and clutch will now be housed in a spec. bellhousing, with the clutch no longer connected to a gearbox input shaft. Instead it will run on an Xtrac supplied clutch shaft supported by a steel ball bearing in a housing that bolts into the new bellhousing. The clutch shaft will drive via a six-bolt CV joint a carbon composite propshaft that uses a flexible coupling technology and drives the rear mounted Xtrac transaxle. The new five-speed manual sequential change transaxle, including a variable preload differential is used in conjunction with independent rear suspension and 18 inch diameter wheels.

The concept of moving the transmission to the rear of the new Next Gen car was to improve driver safety, allowing the driver’s seat to be mounted closer to the centreline of the chassis,  which could not be achieved with the traditional transmission and transmission tunnel; equally the new transmission location offers additional packaging benefits when considering electrification.

The P1334 features an externally adjustable nitrogen gas-charged, positive preload differential, as has been used by Xtrac since 2012, when it was introduced for IndyCar. It has since been used in a host of Prototype, GT, rally and Formula cars.

Along with the P1334, Xtrac is supplying the Next Gen driveshafts including Xtrac high-capacity tripode joints with 38 mm rollers, as used in DPI and LMP1. The driveshaft assemblies feature a retention device, which is designed to keep the driveshaft shaft with the upright in the event of a crash.


  • 5 speed manual sequential gear selection + dog engaged reverse, sequence R,N,1,2,3,4,5,6.
  • Vacuum arc re-melted steel, full form ground ratios.
  • 750Nm (553lbf ft) maximum engine torque.
  • Quick change input drop gear set.
  • High efficiency, full form gear ground and super polished spiral bevel gear final drive.
  • Torque biasing limited slip differential.
  • Tripode output flanges – Xtrac 38mm version.
  • Provision for oil temperature, oil pressure and hall effect non-contacting potentiometer.
  • Large dog ring inspection ports.
  • Nutted shafts for increased stiffness and durability.
  • Aluminium L169 casings with ‘O’ ring spigot sealing.
  • Semi dry sump with twin scavenge pick-ups, featuring removable oil filters.
  • Gearbox weight with standard options, 78Kg (172lb)


  • Cost effective, reliable solution.
  • Active oil cooling ports.
  • Externally adjustable nitrogen charged differential.
  • Fixed ratios reduce track-side maintenance requirements.
  • Extended service intervals.
  • Optimised centre of gravity utilising a hypoid bevel final drive.
  • Overlapping gearchange barrel profile.
  • Drop gear options reduce CWP inventory requirements.
  • Allow driver to be positioned closer to chassis centre line for added safety.
  • Transmission location offers packaging benefits when considering electrification.
  • Wire-lock studs on split faces for scrutineering seals.
  • Magnetic drain plugs fitted as standard.


  • 13 input drop gear options.
  • Low, Medium and High speed CWP options along with cluster options.
  • Road course specific clusters.
  • 4 speed “Martinsville” cluster set up.
  • Provision for gearchange potentiometer fitment.
  • Xtrac 1339 driveline, with or without Ultra High Accuracy MagCanica torque sensors.

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