I just switched to castrol GTX 20W-50
in my gearbox … (2-3 weeks, 2000 miles ago)
and i love it !!!
shifting is much smoother, and overall, maybe it’s just me but it feels much better …
my 2c.
Hmm… a little thick for the tranny, no? I would be somewhat wary of using heavy viscosity oil, especially since Honda recommends 5w30 or 10w30.
But hell… if it works then it works.
-Thomas
why ? what could go wrong ?
what could go wrong with thicker oil ?!
i don’t see anything … maybe gas mileage
a little bit but nothing else … or ?
me.
Well… if you cant see anything wrong with it, then why ask the question?
Honda specifies using a light viscosity oil, hence my first reaction is to think that 20w50 is in the heavier side compared to what is recommended.
Ill take me for example, and how much my tranny is worth
(YS1 w/LSD), and personally, I’d rather not take any chances.
-Thomas
higher viscosity means more drivetrain power loss (less HP to wheels) I would stick to the manufacturers reccomendations on this just my opinion
20w50 seems way too thick, Is it not hard to shift first thing in the morning when its cold??? This is my 6th or 7th, hell I lost count honda product I have owned, all which had manual gearbox’s Currently I am switched to synthetic (Mobil1 10W-30) in my tranny with 170K. Somebody had once put regular 75W-90 Gear oil in the tranny at one point, but thats all gone now. The tranny shifts awesome!!! Try that in there just for shits and giggles. Mobil1 is extremely slick oil!
shifts great …
actually the shifting is just great … and
in cold mornings nothing happens … i let the engine get warm anyway (but this has nothing to do with the gearbox 
…
no, i am definitely recommending this …
the reason i didn’t go with something like 5-10W is that thicker oil also offers better protection especially at high rpm’s and drags …
anyway … i guess that if it works and you’re not racing it, it becomes just a matter of opinion.
r.
Originally posted by InstantRamen
Don’t use motor oil in the tranny. The owner’s manual is kinda vague, but take my word for it-- my gears started to grind after 500 miles. I drained and refilled with Acura/Honda manual tranny fluid and the problems went away. That stuff is expensive but is the only thing I’ll use from now on.
hmmm … i talked to many people about it before,
i even went to some perf shops and asked what they
would use for the tranny and ALL said use regular-thin motor oil … now, i used thicker
just to see how it is … but … i don’t think
you are right. even if you look in the ACURA
Integra factory repair reference manual …
it still says use SAE 10W-30 …
also, it’s been over 2500 miles since i changed
it and i simply love the shifting and also the
feel … before i had some trouble shifting into
first … 1 out of every 10-11 shifts didn’t work
… now i never experienced it again …
anyway …
my 2c,
r.
Originally posted by InstantRamen
A lot of engineering and testing goes into Honda products and there’s probably a good reason why they sell a separate MTF. This link says it all: http://www.richmondhonda.com/faq_oil.htm …scroll down to “Why must I use Honda-brand transmission fluid in my manual transmission?”.
you can’t be serious … you can’t just quote some
people that sell honda products on this …
obviously they’ll sell you what they have …
no, really … this was fun … 
quote me some real people like mechanics and
reviews. again, the acura factory manual says
use normal oil !!!
r.
Didn’t Honda used to use Motor oil in all their trannys? At some point, I guess they figured they could make way more money if they’d just develop their own brand of tranny fluid and sell that too along w/ motor oil…
Personally, I’d just go w/ tranny fluid. I mean, comparing tranny fluid with 20W-50 oil is like comparing grape juice and syrup! … (as far as viscosity goes) …
hmmm …
well … i’m not an expert either …
i might be wrong … but it seems to work
great for the past 3000 miles and synchros
don’t grind etc etc.
anyway … pobably MTF is better or at least
as good …
r.
archivethis
ditto to the honda mtf. atf for me. not even expensive either, just a few bucks from the local mom n pops shop.
Sure Honda/Acura sells the MTF at the dealer for like $5US more or less…but I spoke to 1 of the mechanic at my dealer, they say they put 10W-30 in the tranny unless the customers request it (which means more $).
BTW the manual states either 10w-30 or 10w-40. I might try the Honda MTF on the next change and get my own opinion on the stuff =).
Ken
I put synthetic blend oil in my trans. for a couple years. It seemed to shift fine…hardly any troubles except for a scratch here and there(probably my own fault). Then I switched to Honda MTF just because I was curious. Now, with 195K miles, when I first start the car it’s harder to get it in gear. But once you’re rolling it gets easier. Weird.
I’ve heard on this website that synthetic oil can ruin your synchros but there was no hard proof from that source. I’d be interested to try Mobil 1 synthetic.