Many people are using the synchromesh type fluids in Hondas, specifically the AC Delco Friction Modified Synchromesh. Read the reviews. I have it in my Corolla (totally wrong viscosity), it went from almost needing a rebuild from a notchy 3rd gear syncro, to shifting like brand new. It's the best manual transmission fluid out there IMHO, especialy now that most vehicles call for thinner fluids. Mine specs 75w-90 which is 15 cst at 100c, the synchromesh is 9 cst. Works awesome, has been for 40,000 miles and no failures to speak of going to such a thin fluid.
https://www.amazon.com/ACDelco-10-4014-F...iction+modified
This is "The Fix" for Honda/Acura manual transmissions!
October 27, 2016
Verified Purchase
I will admit I was more than a bit skeptical, but now I'm a True Believer!
I had a 2009 Honda Accord (4 cyl., 5-speed transmission) with a "notchy" 2-3 shift that the dealer couldn't fix. However, I didn't worry about it too much, as it was a "lease" car. When the lease was over I bought another Accord (6 cyl., 6-speed), and I was quite surprised to find that I had the same issue! In an effort to fix the issue (this car I'm going to keep), I visited several dealers, one of which told me that they would have to install a new transmission- but at my cost and not under warranty!
After perusing the Honda forums on the "interwebs" I learned this a common issue with Honda transmissions, and that the fix is to replace the OEM fluid with this GM fluid. So, after my warranty expired, one of the first things I did was change-out the fluid, and.....
What a difference! The "notch" in the 2-3 shift is GONE!
So far I have over 2K miles with this fluid, and the transmission hasn't "stumbled" once!
HIGHLY recommended for Honda/Acura vehicles with manual transmissions!