2003-2009 Toyota 4Runner and Lexus GX470 SUVs are prone to a gear oil leak from the transfer case, V6 or V8 powered, where the transfer case shift actuator mates to the back of the transfer case proper. We’ve covered the replacement of the transfer case shift actuator in another blog and the repair procedure is largely the same: remove the transfer case, dissemble the transfer case until you release the actuator, swap the actuator o-ring that is leaking.
Here’s where the leak comes from (an up close of a V8 powered 4Runner):
Transfer Case Leak
The repair is deceptively complicated. Simply pulling the transfer case actuator off the back results in a destroyed actuator – the internal motors that move the select forks/shafts become misaligned and can’t be repaired. The actuator then requires replacement. To remove the actuator you must pull the transfer, disassemble the case, and slide out the actuator:
Transfer Case Actuator (not leaking in this photo)
Transfer Case Open
The shafts that are connected to the highlighted cogs and select forks need to be unbolted and unclipped before the actuator can be pulled carefully out the back.
Because the transfer case needs to be removed and rebuilt to replace the leaking actuator o-ring, this is not something CARspec recommends a non-professional try and tackle.
As Minneapolis, Minnesota’s premier Toyota, Lexus and Scion specialist, we repair GX470 and 4Runner transfer cases often and have all the needed tools, special fluids, and experience to perform the job correctly the first time. I’ve you’ve got a leaking GX470 or 4Runner transfer case, don’t hesitate to give us a ring at (952)426-2798 to schedule an inspection today!
