i know Honda does not recommend ANY lubricant additives, and i wouldn't normally use any. out of curiosity, i did use a product called instant shudder fix, (recommended by some on this forum) it is a napa auto parts product # 765-2969 ( 2oz.tube of licquid ) $6.75 i did this in an attempt to cure a "mild" shudder experienced while driving up-hill, during the 3-4 upshift. . i added it to a warm transmission on 8/23/2016 @ 222,955 miles. for my car, it worked immediately. shudder was gone! as of today, 4 mos and 3,200 have elapsed and still no shudder. today i received the results of the second transmission fluid analysis by blackstone labs. according to the lab tech., "FRANK: Thanks for the note about the "Shudder Fix" additive. It doesn't look like that stuff contains
anything unusual since these additives are similar to what we typically see from Honda DW-1 oil, and that's
fine. Did it help anything on your end? This run was a little longer than the last, so the extra iron is okay.
The increase at aluminum shows a little more torque converter or oil pump wear, but not enough for us to
call a problem. If you're having issues, maybe the increase at aluminum provides a clue. From what we see,
all is well. Just check back next time to monitor." needless to say, i'm relieved the additive does not appear to have had any negative effects. regardless, the transmission will come out next spring and be replaced by the av6 i have on hand.

 

I have used instant shudder fix and highly recommend it. I used it on my 07 Grand Caravan, around 85k miles i started to get shudder here and there and put some instant shudder fix into the tranny and now at 120k miles and tranny is working perfect.