What's the best manual transmission oil?

[Grindal]

According to my 90' Honda CRX shop manual Honda recommends 10w30 - If you live in an area where the temperature doesn't drop below 0 Fahrenheit you can use 10w40 or 20w40.

Attached is the page from the Manual.

[ChazInMT]

Zombie Thread.....ARISE!!

Hey, the 1990 manual page is a cool thing to put in here. I'd say if you have a 1990 car you want to put the 10w-30, or 10w40..Go for it.

I know fer sure my 2004 Honda Owners Manual says use the Honda MTF, but if yer in a pinch, use motor oil, But, Replace the Motor Oil with the Honda Stuff ASAP.

I have been in other Honda specific forums where guys who are veteran mechanics are adamant about using only the Honda MTF oil, it is the only thing I'd ever put in my 04.

[slowmover]

Honda is a world of its' own. Good advice.

[user removed]

I read somewhere that the motor oil that Honda recommended in 1990 had additives that are no longer in the oil. Basically that means that the old recommendations are no longer valid. Your best bet is the fluid Honda provides for their new manual transmission cars. I can't remember where I read this information since it was two years ago when I sold my VX, but I changed the transmission fluid and used the Honda fluid. It doesn't take much and one of the weaknesses is the input shaft bearings in the Honda transmissions. If you don't have any problems with your transmission then personally I would use the fluid Honda currently recommends.

I learned this lesson the hard way a long time ago when I changed the fluid in a BMW 2002, only to find out later that BMW used mineral oil in their transmissions at the time. Had to replace all the synchros in the transmission, a $600 mistake in 1975, I'll never forget.

regards
Mech

[Grindal]

I went ahead and bought 10w30 Synth oil from Amsoil to put in the manual tranny. Anyone see an issue with using this oil? It's what Amsoil recommends for my 90 CRX.

[jasonst]

Originally Posted by Grindal

I went ahead and bought 10w30 Synth oil from Amsoil to put in the manual tranny. Anyone see an issue with using this oil? It's what Amsoil recommends for my 90 CRX.

I think that's a very wise decision. Amsoil makes a great product. I'm curious about and leaning towards this in my 90 CRX HF:

[Ladogaboy]

Just my opinion, but I think Amsoil is over-priced for what you're getting. I'm not going to go so far as to say oil is oil is oil, but the top rated manufacturers are all a safe bet. It just so happens that Amsoil is twice as expensive, and they justify it by saying that their oil will last 5-10x longer.

[morphector]

2 types of std transmission oil that I like:
gm syncromesh
ford manual transmission fluid (with a steep 31$ a pint)

[forums123]

A toyota mechanic I ran into at the local autoparts store said he used to drive a honda and he said not to run synthetic in a honda manual tranny because the synchros need a certain amount of friction to work properly. He said synthetic is too slippery and will cause you to grind your gears and also lead to premature tranny failure. Sounded pretty sensible but also dissappointing as I was hoping to improve my fuel economy by running a lower friction synthetic oil in the drivetrain. On the other hand I would hate having to replace/rebuild my tranny, as the cost would seriously offset any gas savings from running synthetic oil in the tranny.

I like the recommendation to use Honda MTF but I am curious does Amsoil provide any kind of warranty or gaurantees their synthetic mtf will not damage a honda tranny?

[WesternStarSCR]

One thing I learned on my recent Toyota is that is important to find the correct SPEC (GL-4, GL-5, and / or MT-1) that your particular owners manual and / or Field Service Manual may be calling for in your vehicle.

For the Corolla / Matrix / Vibe / Corolla xRS platforms (C59 - 5 speed and C60 - 6 speed), there is a lot of discussion on Toyota Nation.

The important take away is that the preferred is a GL-4 only spec, such as Red Line MT-90. The Gl-4 Spec ensures that 'yellow' metals such as brass in the bearings, are not corroded, and that there is enough of the correct additives to allow the syncros to work without slipping too much.

People have found, at least in these cars, if they went with a GL-5 ONLY or MT-1 ONLY spec, it was notchy shifting.

Supposedly Toyota manual or FSB said Gl-5 is OK. The take away is that it MAY be OK, but for bearing life and smoother shifting, the preferred by owners is either a GL-4 ONLY, or a GL-4 & GL-5 spec.

But not a GL-5 spec only, where GL-4 is not listed anywhere on the bottle.

Personally, I just added Valvoline conventional lube, that specs both GL-4 and GL-5 on the bottle. It is hard to find a GL-4 only lube at a store, so most just order them. I was OK with the $6 a quart for the Valvoline for my case, and 80W-90


From TN:

Gear Oil for M/T:

Most agree on a few good oils. The Toyota C59/C60 needs to have a GL4 oil to prevent damage to the yellow metal inside the transmission. Synthetic gear oil is amazing and works great in the cold for smooth buttery shifts. Replace all every 30K.

Redline MT90: My favorite. Available on Amazon or from Redline for about 13 bucks a quart.

Product Data sheet: Red Line Synthetic Oil - Gear Oil for Manual Transmissions - MT-90 75W90 GL-4 Gear Oil

Amsoil Synthetic Manual Transmission oil: Another highly recommended yellow metal safe oil.

Product data sheet: AMSOIL Manual Transmission & Transaxle Gear Lube 75W-90

Royal Purple Max Gear: Well recommended, yellow metal safe oil.

Description sheet: http://royalpurpleconsumer.com/produ...ive/#!max-gear


Relevant links:

DIY Manual Transmission Fluid Change - Toyota Nation Forum : Toyota Car and Truck Forums

Read Me: Official 9th Gen Maintenance Thread. All you ever wanted to know!! - Toyota Nation Forum : Toyota Car and Truck Forums