My '08 RL has been shuddering and growling at low RPM in 4th and 5th gear. It usually occurs at 1500 RPM (+/- 200 RPM).

It sounds exactly like the problem the 4th gen TL's were having discussed here:
Anyone do the torque converter transmission program recall?

ZachTaylor's thread posted here in the 2nd gen RL forum is somewhat similar:
Strange...trans stays in 4th gear at 30mph, shudders

This is my first car with an automatic transmission, so I'm just guessing here, but it feels to me like the torque converter is oscillating. Like it can't decide whether to lock-up or not.

I tried to grab a video of it tonight. Skip to 30 seconds and the growling/ oscillating tachometer will start shortly after.


I had a trusted Honda mechanic look at it, but they weren't able to duplicate the problem. Probably because they're located in the city and weren't able to get the car into the right conditions for the problem to occur.

If you guys think it's the torque converter, then I'll just drop off the car and tell them to change it. I'm expecting at least couple thousand dollar repair bill. Hopefully it's the TC and not the trans.

 

Your video is private and we cannot see it.

Go to https://acurazine.com/forums/second-generation-rl-2005-2012-76/transmission-stall-speed-test-906321/

Carry out stall test and share the result.

 

The shuddering you note in those gears at those rpms is consistent with a tc issue. Mine shuddered at the bottom of 4th gear, around 37 mph. Never really heard it in 5th. Replaced under warranty.

 

Sorry about that, the video is now unlocked.

I don't hear it or feel it so much in 4th gear. It seems to be mostly a 5th gear problem. It'll start around 35 mph, but the noise is the loudest right at ~50 mph and usually stops after 55 mph.

 

when was the last fluid change for the diff and trans?

 

The rear diff fluid was changed 2 weeks ago. I don't have any record of the transmission fluid being changed. That's a good idea, though. Wouldn't hurt to have that done as well.

 

Blazin, have you had a chance to do a transmission fluid change? Did it help?