Driveshafts Technology for Passenger Cars

March 2007.

GKN Driveline is the acknowledged world leader in constant velocity joints with a market share of over 40%. All major car makers in the world use drive shafts by GKN Driveline. GKN Driveline’s global market leadership is based on a strong engineering heritage and 21,000 people in more than 40 locations in over 30 countries.

The right idea at the right time

At the end of 2005 GKN Driveline Engineers announced two major breakthroughs in constant velocity joint technologies which are exciting the interest of the vehicle manufacturers all over the world: The Countertrack technology for fixed joints allows angles of rotation as great as 52°. The races of the 8 balls in a cage are not just opposed, they have been made into an S-shape. The new technology has the ability to reduce the weight of the shaft by up to 35% thus reducing vehicle weight, i.e. of 4.0 kg of a typical FWD mid size car in production today. It also improves driveline efficiency – keys to improving fuel economy and performance.

The Crosstrack technology for ball plunging joints will dramatically improve driveline noise, vibration and harshness (NVH) in a vehicle.
Both joint technologies may be used for front wheel side shafts as well as for propeller shafts.

SPIDAN and LÖBRO – original GKN brands for the independent aftermarket
Through the GKN Driveline product brands SPIDAN and LÖBRO - the original GKN drive- shafts technology is available to the independent aftermarket. Dealers and workshops benefit from the market leadership and the technical know how of the OE supplier of driveshafts in many ways.

With a product range of driveshafts, joint kits and boot kits for more than 40,000 car applications original GKN parts provide the largest product range for replacement passenger car side shafts and repair kits – the right parts for each individual application.

Material and production processes are to OES specifications, supplying maximum safety in the car. Extended services such as overnight deliveries, printed and online parts catalogues including technical specifications and detailed assembly instructions, professional trainings  as well as marketing and advertising provide additional benefits for parts dealers as well as for workshops.

Recommendations for the correct handling of driveshafts

Driveshafts and constant velocity (CV) joints are bespoke components in modern cars for which high quality is critical. They transfer torque from the differential to the wheel and are therefore constantly subjected to extremely high stresses when the vehicle is in operation. As a result age-related wear is among the most commonly occurring causes of damage to the outboard (wheel side) and inboard (transmission side) joints, closely followed by damage resulting from defective boots, the use of inferior quality grease, and unfortunately, improper handling frequently occurring during installation and removal.

Routine inspection steps for driveshafts, CV joints and boots

Built-in driveshafts

• Check the driveshaft for a tight fit
• Check cleanness of the driveshaft (no greasecontamination)
• Check the shaft for damage and for bent or missing parts
• Check the boots and clamps: torn, slipped and porous boots are the most requent cause of failures
• Check the slip spline for excessive radial movement
• Check the joints for excessive radial looseness
• Fixed joints: Check the joints in all possible steering angles

Removed but not dismounted shafts

• Place profile tube in a vice
• Imitate the fixed joint’s rotation. The joint must be movable smoothly without any bucking
• The fixed joint must have no excess radial movement.
• Place profile tube in a vice

Boots

• Do not twist the rubber boot during assembly
• Before mounting the circlips, bleed the boot
• Use new circlips and the special mounting tool.
• When mounting the stainless steel tension fitters of TPE (Hytrel) boots, pay attention to the torques

Where replacement is required, GKN Driveline provides good removal and assembly instructions for SPIDAN and LÖBRO driveshafts, CV joints and boots. To support the correct handling, GKN Driveline offers a range of high-quality tools.

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