Late model Toyota Rav4 vehicle with optional all wheel drive have a common problem we’ve been seeing pop up as they age, namely a fluid leak from the rear differential. Most of the Rav4s with the issue have multiple seal leaking (both axle seals and the front pinion seal). Because the rear differential is packaged with a magnetic coupler the problem can often be misdiagnosed.
The root cause of the issue is the rear differential vent on top of the assembly. Here’s the differential out of the car with the vent and leaks highlighted:
Rav4 Rear Differential
The vent plugs up causing pressure to build inside the rear differential, the seals failing under the pressure. Even if only one seal leaking it is critical to replace the rear differential vent (even if it appears to be OK) with the updated part to prevent the leaks returning soon after a repair (we rarely see only one seal leaking on these when the vent plugs up though). Here’s the magnetic coupler removed:
Rav4 Rear Diff Apart
And here’s with the magentic coil removed revealing the seal race (seal has been removed):
Rav4 Rear Diff Apart Further
If you do take the differential apart this far be sure to measure the seal depth before removing it.
For the above differential both axle seals and the front pinion seal (behing the magnetic coupler) were replaced along with the updated vent. The entire assembly was also cleaned prior to reassembly as fluid has a tendency to pool leading to residual messes. Failing to replace a plugged vent will result in all the seals leaking again.
If you have a leaking Rav4 rear differential, don’t hesitate to give Minnesota’s premier Toyota and Lexus specialist repair shop a call for an inspection at (952)426-4798 today!
