Automatic Gearbox Flush … but it says filled for life?

The oil is supposed to be lifetime fill on my Land Rover – why change it?

This is some of the information from ZF who manufacture automatic gearboxes for most Land Rover and Range Rover models and a little of our own advice when it comes to deciding if it’s worth servicing your gearbox


• The oil in a modern automatic transmission is a highly engineered component as it serves many functions including lubrication, cooling, hydraulic application of clutches and power transmission via the torque converter
• Modern transmissions utilise overlapping application of clutch packs at gear changes (instead of freewheels) and controlled slip of the torque converter lock up clutch which puts greater stresses on the oil
• To meet these challenges partially synthetic oils have been developed for ZF 5, 6 and 8 speed transmissions which are maintenence free under normal operating conditions. However, as some degradation of the oil inevitably occurs over time and usage, ZF recommends oil and
filter changes after 50,000 to 75,000 miles to ensure optimum performance.
• Oil degration can lead to complaints such as judder, noises and a deterioration in gear change quality.
• Some car manufacturers already recommend oil servicing at
60,000 miles and others are starting to put greater emphasis on
the technical benefits rather than ‘cost of ownership’.


Why use approved oil?


• There were many approved oils for the simpler 3 and 4 speed transmissions, however, it is only feasible to exhaustively develop and test one oil to meet all the demands imposed on a modern transmission.
• Claims are made that alternative oils are equivalent but whilst they might have same basic characteristics such as viscosity they won’t have the same crucial additive packages which are closely guarder secrets of the oil companies

Will a gearbox flush fix gearbox problems ?

A gearbox flush should always be considered as a preventative maintenance procedure and part of the routine maintenance of a vehicle. The aim is not to use it to repair. There are many cases where the transmission has been diagnosed as faulty but a gearbox flush has brought the vehicle back to a drivable state. This is sometimes long term and sometimes short term. However every vehicle is different and we cannot guarantee the outcome until the service has been carried out

There are many issues an automatic transmission can suffer that no amount of oil changes will prevent. Given the cost of repairing (or worse, replacing) an automatic transmission, it’s not worth risking the issues an oil change can prevent

If there has been a treatment fitted such as Dr Tranny a gearbox will feel worse after a flush if it’s been hiding issues. Any service history you have will be important to see when considering what to do next

Why use a flush ?

Simply put, changing oil in a gearbox by dropping the oil alone does not get all of the oil out. When dropping oil you get 45-60% of the oil out and mix the fresh with this older oil. When you are doing a gearbox flush you get out 92-95% at least.

We offer a gearbox flush for all automatic gearboxes and you can book by calling 0191 4698740 or email info@spannermonkeys.co.uk