Honda MTF

What weight grade is Honda's manual transmission fluid? Two different
dealer parts departments that I spoke with did not have an answer. I was
also wondering if anyone knows who manufactures this oil for Honda? Is
there an equivalent non-Honda lubricant, i.e., same specs, same
manufacturer, but different label? I have also read that Honda's fluid is
better than regular 10w/30 since it has a higher zinc content but the
dealer's parts department could not confirm this. It would be great if
someone could post some definitive information.

Thanks, Eric

 

Gear oils are graded using a different system than engine oils, so the
numbers are not correlative. A 20w weight engine oil has about the same
relative viscosity as a GL70w trans oil.
http://www.cloverleaf-auto.com/oils.htm

Honda MTL pours a lot like a straight 30-weight engine oil at room
temperature, and Honda originally specified 10W-30 motor oil before
sulphur-phosphorus and zinc were removed, so my guess it's still equivalent
to a 10W-30 engine oil.

Might be Exxon Mobil. This stuff may be it:
http://tinyurl.com/6ox6n

Unless you're an insider, you'll never know for sure. Just like you'd never
know that Canadian-market Acura MDX seats are made by Faurecia and Civic
interior trim is made by Kumi Canada unless I told you so.

Consult your friendly local tribologist. Don't know one? Neither do I.

Considering how cheap the stuff is compared to what else you spend on your
car every year, I just buy it from the dealer.

There are a number of anti-wear additives, not just zinc dithiophosphate.

 

Thanks for the info!

Eric

 

Unless it comes in a lighter grade, then this product is not a likely
candidate as putting 80w-90 in a Honda manual tranny will kill it.

Eric

 

That's sounds a lot like you don't understand gear oil weight rating.

What weight would you recommend?

 

I read that gear oil numbers are not equivalent to engine oil numbers. That
stuff may be the same viscosity as 10W-30 engine oil.

 

I'm not sure. 90W hypoid oil (that nasty sulfurous-smelling stuff) is a lot
heavier than any motor oil. Beyond that, I don't know.

Mike

 

I don't think you can compare EP (Extreme Pressure) oils with ordinary
oils.


Doin' some diggin' here...
http://www.lotuselancentral.com/trannyoil.htm
http://www.redlineoil.co.uk/products/products.htm
http://www.spectro-oils.com/gadata.htm
http://www.greerracing.com/index.php


Gear oil numbers ARE different. From the Lotus link:
"75W90 gear oil has the same weight and viscosity properties as 5W30 motor
oil".

 

----------------------

Who needs to save a few bucks? It doesn't take five quarts does it? For
the difference a quart or two might cost, at least you'll know that the
Honda stuff has all the best additives that a Honda tranny needs. If we
can judge by the (terrible) results people get when they try using
'alternative' tranny fluids in their Honda automatics, it's just NOT
WORTH IT TO CHEAT. Cut back on coffee, spend the difference on your
tranny MTF.

You were probably going to substitute something that was even more
expensive, no?

'Curly'

 

and from the Greer Racing link, "engine oil and gear oil have their own
specific viscosity rating system. As such, the viscosity of 75-weight gear
oil is equivalent to 10-15-weight engine oil."

Huh. Could be just working with the smelly stuff made me think it was thick
and gooey. All oil really gets everywhere if you let it, and the awkward
angles for adding gear lube make it messy.

I did find this link for how motor oil viscosity is measured, for the
curious
http://www.type2.com/library/mainten/oilw.htm
but so far nothing on how EP oils are measured.

(The Lotus Elan site reminded me of my youth when I had a Lotus Europa. Did
you see that improvised tool picture?)

Mike

 

For what it's worth, I have 10 years of professional experience as an ASE
certified tech. Six of those years were spent working in an independent
Honda shop, where among other things, I rebuilt engines and manual
transmissions. I have personally rebuilt Honda transmissions that had been
ruined due to the fact that they had the heavy 80w-90 gear oil in it. If I
remember correctly, one of them had the differential fail. This was not a
typical failure and it was attributed to the wrong oil installed in the
transmission. This was over 9 years ago and I don't recall whether or not
Honda MTF was available at that time. The owner of the shop has a degree in
mechanical engineering. Under his guidance, and Honda's recommendations at
that time, the shop used 10w-40 oil for manual transmissions. I believe
that they are now using a synthetic gear oil though I don't recall the
specifics right now.

Eric

 

Original spec for my '85 Civic transmission oil was 1-W-30 motor oil.
As a long-time motorcycle mechanic, I hadn't much liked motor oil in
transmissions, have been using motorcycle trans. oil (Bel Ray),
currently at 282.000 mi. and going strong. I would expect Spectro's
gear oil to work well also - I just prefer Bel Ray in my bikes, so
that's what the car got.


Tom Willmon
near Mountainair, (mid) New Mexico, USA

Net-Tamer V 1.12.0 - Registered

 

It still sounds like you don't understand gear oil weight ratings.
You DO realize they are measured on a different scale, right?

80 gear oil is about 8 to 11 cSt.
90 gear oil starts at 14 cSt.

10 motor oil is about 4 to 6 cSt.
40 motor oil is about 14-17 cSt.

So, 80w-90 gear oil is *slightly* heavier when cold that 10w-40 motor oil.
Slightly.
A better choice would be 75w-80, which is bang on a 10w-30 motor oil, but
has the anti-shear additives that motor oil doesn't have, but gear oils
need.