Q.
Trawling through the internet, I’ve noticed a number of issues relating to Freelander 2 rear differential failure. Land Rover apparently issued a technical service bulletin (LTB00342/2010) detailing a repair procedure for dealers. Does this affect all vehicles, or just a handful? Is it worth changing the differential oil at regular intervals?
A.
There have been concerns with the Freelander 2’s rear differential and the attached Haldex coupling that apportions torque to the rear wheels. This potential trouble spot is well-known, but relatively few vehicles have been affected.
The technical bulletin you refer to was revised in 2011 and now covers model years 2007 to 2011 and VINs 000212 to 257090. It refers to pinion bearing damage attributed to the way in which the coupling applies torque when moving away from standstill or during slow-speed manoeuvring, causing overload of the bearing. Symptoms include a humming sound, a high-pitched whine or a rumble from around the rear differential.
An improved fourth-generation Haldex coupling was fitted from the 2009 model year, which also includes some late 2008 Freelanders. This coupling can accept updated software that controls the torque application to the rear wheels, and hence the load on the pinion bearing. It would normally be necessary to update the software if the bearing or differential had failed and was renewed.
The fact that this update is applied retrospectively only when the bearing showed symptoms suggests there is no great concern about this issue.
A diagnostic check is needed before investigating symptoms. For example, the message ‘traction reduced’ with the relevant trouble code may mean a poor connection on the Haldex sensor. If the connectors are serviceable, the next step before considering the diff is trying a new pressure sensor, for which an adaptation routine needs to be carried out using diagnostic kit.
The rear differential oil is scheduled for replacement at 150,000 miles or ten years, whichever is sooner. A more frequent oil change won’t help if the pinion bearing is suffering static overload. If the symptoms are present and the problem is confirmed, the damage will have been done, and the only course of action is to renew the bearing.