I think I'm losing the planetary gear in my OD on my '01 4runner. From what I've read, this was a weak link in the early 00s 4runners and Tundras. I could be completely wrong though (hopefully). Here's a video of it.


I've already checked the following:

Cats
Muffler
Skidplates
Heat shields
Transfer case damper
Suspension
Shift linkage
Felt around the top of the transmission
Banged on anything else I can find with a rubber mallet

I'm currently running Amsoil and have 248k miles (owned since 190k). I do have a Magnefine filter. The sound still exists in 4HI so I don't think it's the transfer case. It literally only happens in OD. The speed of the sound slows down as I'm coming to a stop before it shifts out of OD. I'm out of ideas at this point other than the transmission. So any others you guys might have are definitely welcome.

Let me know what you think or if you have any questions. I really appreciate the help.

 

Does seem really strange, a video makes everything sound strange though. I suspect a cracked flex plate since that is the only common issue found in that area, but I'm only guessing at this point without experiencing it.

 

I want to give an update for anyone else with this same issue. I saw a transmission guy who confirmed the problem. The planetary gear in OD is going out. I'll likely be pulling the transmission this weekend. Dealer wants $2300 for a reman without a torque converter (with a hook-up). I'm going to get it built on the side for $1000. Plus I'll buy the torque converter and anything else that is needed. I normally wouldn't do a side build. However, the guy builds race transmissions for a bunch of people and knows this transmission. So I'm going to let him work his magic on it. He's going to do some valve body work while he's in there as well.

Too bad this isn't as simple of a fix as the Tundras (just swap in an '03-'04 tranny). Oh well, I'm hoping to get it all said and done for under $2k. Fingers crossed I can pull it off.

I hope this helps someone in the future.

 

Looking forward to your progress on this - the sound is certainly disturbing!

My 4Runner is the first automatic transmission vehicle I've ever owned and I remember having some hesitation when I purchased it new nearly 16 years ago. But it was the only transmission choice in 2001.

i now have 373,000 miles on it and am continuously amazed at how reliable this truck has been. I've had the transmission flushed every 100,000 miles with Toyota fluid - it still shifts and behaves the same way it did when new.

I hope your rebuild goes smoothly.




Andreas