Z1 Street Pro R190 Limited Slip Differential was produced exclusively for all 2014+ Infiniti Q50 and 2017+ Infiniti Q60 models. The nature of the factory open differential leads to dangerous conditions especially in high power, high boost cars. The benefit is not only on acceleration, significant improvements are experienced in corner entry, overall cornering stability, predictability when driving the car at the limit, and leads to a generally safer and more controlled driving experience.

Z1 Street Pro Differential

The factory differential in all Infiniti Q50 and Q60 is a standard open differential. The biggest flaw with open differentials is their inability to distrubute power between both wheels. With an open differential torque is applied equally between both wheels, however in situations where wheel slip occurs (such as rapid acceleration) the slipping wheel will receive almost all torque. This imbalance between the left and right wheel leads to poor cornering stability and poor straight line acceleration, infamously known as the "one wheel peel". Infiniti combats this problem using "Electronic Brake Force Distribution". This form of stability/traction control applies brake pressure to individual wheels across the drive axle (literally dragging brakes! Slow the car down to speed it up?) to regain control in low traction scenarios. While this does help manage stability, it's important to note that this is no substitute for a proper mechanical limited slip differential. Dragging both rear brakes to equalize torque distribution will also impact acceleration, our differential manages this without the added braking.  

The Z1 Limited Slip Differential is a helical differential that is a dramatic improvement over open differentials given its considerably greater ability to distribute torque at both wheels. With its internal gear design, it boasts exemplary street manners and is operationally quiet when compared to clutch type differentials that have a tendency to chatter or clunk when cornering at low speeds because of axle bind. The Z1 SP-Pro differential is a helical unit that exhibits no axle bind and provides smooth operation in any circumstance. Seriously, your wife won't even notice you upgraded this thing. Because of the internal construction the Z1 SP is low maintenance (only regular fluid service intervals) and ensures exceptional life span with no special fluids or friction modifiers needed. Standard fluid may be used, however Z1 recommends the use of Red Line or Motul differential fluid found in their respective links to the left.

Installation Note

Please keep in mind that the differential in your Q50 / Q60 is new and service tools may not be available at driveline shops in your local area. It is VERY IMPORTANT that this installation is done by a competent and experienced driveline shop. Incorrect gear lash or pre-load will result in accelerated wear, noise, etc. As a convenience, Z1 offers this differential as a fully assembled drop in unit with core exchange HERE. Also available in this service is a Red Sport gear upgrade. More details can be found at the above link.

If you choose to locate a driveline shop for installation, we recommend purchasing new side bearing and side axle seals. As a convinience, this has been included as an option below. (different spec side shims may be needed for install - available seperately HERE)

Features:

• No Maintenance
• Great Street Manners
• Robust Build Quality
• Low Noise - Chatter Free!
• Improved Power Delivery and Handling
• No Special Fluids or LSD Additives Required
• Improved Power Delivery and Handling
• No More One Wheel Emarassment at the Drag Strip
• Build Service Available - Simple Install!

Fits:

• 2014+ Infiniti Q50 Sedan
  • 2WD and AWD 2.0t
  • 2WD and AWD 3.0t
  • 2WD and AWD 3.7l
• 2017+ Infiniti Q60 Coupe
  • 2WD and AWD 2.0t
  • 2WD and AWD 3.0t

*This differential does NOT fit 2014-2015 Q60 Coupe*

*** This item does not qualify for any additional discounts or promotions ***