Monday, July 15, 2024 Detailed Auto Topics
You May Also Like
AGCO Auto Quick Tip:

Try our new Category View for Detailed topics segregated by their topic.

Now it's even easier to find the information you need.

AGCO Auto Quick Tip:

You can also receive our Detailed Auto Topics, delivered to your computer, as soon as they are written, please subscribe to our RSS feed.

AGCO Automotive Detailed Topic Blog


Detailed Topics

The most common failure symptoms in differentials are noise and leakage. While they are often mistaken as the problem, both are more often the symptom of another problem. For instance axle seal leakage often indicates a worn axle shaft, bad axle bearing or a plugged vent tube. In this picture oil can be seen on the brake backing plate of the left rear wheel.

Oil on backing brake plate indicates leakage

Once the rear wheel, brake caliper and brake rotor are removed, the nature of the leak is easier to see. The rear parking brake shoes are also contaminated with oil and will have to be replaced.

Leaking rear differential axle seal with oil on parking brakes


Removing the axle shaft shows the actual problem. This axle shaft is badly grooved from a worn bearing and causing the leakage.

Damaged rear differential axle shaft


The right side axle seal is also leaking, to a much lesser degree.

Right side axle seal leakage


While bad axle seals allow oil to leak out, they can also allow water to leak in. This can be a far worse problem. The milky colored oil in this differential indicates water contamination of the lubricant.

Corrosion damage caused by water contamination


The ring gear has been damaged by corrosion and is the source of noise in this differential.  These gears will need to be replaced, at considerable cost.

Corrosion damage to rear differential ring gear caused by water


Water also often enters a differential through a damaged vent tube. In this instance this is not the case as the vent tube is still fully intact. Driving though water, above the height of the axle can allow it to enter the differential.  This is particularly bad if the axle seal is leaking.

Water entered this differential even though the vent is intact


Best is to avoid driving though high water and have leaking seals addressed immediately.  Professionals like AGCO Automotive can spot and often prevent more serious damage.  Properly servicing this differential might have prevented an expensive rebuild, replacing the ring and pinion gears.  Avoiding repairs rather than simply repairing damage, that's the AGCO way.

Post or Read Comments (2)

Please click the link above to leave your comments


Registered visitors are always invited to leave their comments and thoughts by using the form above. If you need to you can login here or register here.

You can also win a free AGCO coffee cup, by reporting any errors you find, with this form.