This is just a quick write up of an issue I just experienced with my 2017 Honda Pilot for those of you out there who may own one. I've found several folks online describing the exact same problem however the diagnosis seem to be all over the place.
A few months ago when my Pilot had about 45k miles on it, I started noticing a strange pulsating feeling went I would drive it under light throttle load between 20-30 mph. The transmission didn't feel like it was trying to shift however the RPM gauge would fluctuating up and down about 500 RPMs. I thought maybe it was the throttle position sensor etc. I'm not normally one to involve the dealership service department in the maintenance of my vehicles, however since the power train warranty was still in effect for another two months I gave them a call and made an appointment. On the phone, Service Manager suggested that the ATF may need to be changed. I thought this was odd because I was under the impression that the service interval is 90k and I was only half way there. Unfortunately I had to cancel the appointment at the last minute and a few days later decided to just drain and fill the fluid myself to see if it made a difference. Incidentally, I asked my wife when the last time she had her Pilot's (90k) fluid changed and all I got was a confused look (not a good sign); so I ended up doing both of them at the same time. I filled with Idemitsu's H+ DW-1 fluid and the pulsating issue seemed to go away. That evening I was surfing the web and stumbled over a Honda Service bulletin on the issue that someone had published. He mentioned that he also had the same problem and that it seemed to go away after a drain and fill but the problem still persisted at low RPMs between 5th and 6th gear. Jumped in my Pilot and took it for a spin, sure enough I found mine still had a slight pulsating under the same conditions. Called the dealer, rescheduled the appointment.
So anyway, apparently Honda recognizes that "under certain driving conditions the ATF may wear out prematurely". Service Bulletin 17-014 addresses "Judder from the Torque Converter Lock-Up Clutch". The remedy (on Honda) is to drain and fill the ATF three times in a row and then update the firmware on the transmission to keep the fluid from getting too hot, and then give a warranty extension to 80k. The tech working on it had a difficult time trying to replicate the issue, apparently they need to "capture the logs" and upload them to Honda for analysis. Two test drives and two office catering pick ups later they got the info they needed and got Honda to approve the procedure.
I guess what really gets me on this is - if it's 90k fluid why on earth is it wearing out at 45k? I can understand if it's driven hard, maybe 75k or 80k, but half the expected life? I don't tow anything with the vehicle, all I can think of is several trips down to the beach with a roof box, bikes on the back, and everything my wife can stuff in the vehicle put a heavier load on it than expected. I'm considering adding the official Honda transmission cooler.
Apparently the Honda DW-1 fluid isn't even synthetic, I'm thinking about draining an filling it again in 30k with the Eenos import ATF. Fluid suggestions?oop