Squeezer

Would this hurt the tranny in any way? I'd like to start using it rather then Honda MTF since I use it in my diff.

honda606

Yes it would. Gear oil is for the differential and Transmission fluid is for the transmission. DO NOT USE Gear oil in your transmission.

Get some Redline MT-90 transmission fluid, AMSOIL, or some other equivilent if you want something other than Honda MTF.

cdelena

It is a GL5 lube designed for differentials. It is likely that the EP additives will damage some parts, beside the lube being too heavy for this transmission.

Squeezer

Ok well I was just confused then, because auto parts stores carry ATF and gear oil, but not MTF and I've known people that use gear oil in their manual cars and never had a problem. I've always wondered why auto parts stores carry ATF and gear oil but no MTF fluid. Anyway, I'll go with Honda MTF when my tranny fluid needs changing, thanks!

honda606

Squeezer,

You can order Redline Synthetics now from the S2ki store at quite a nice price. Perhaps you should consider that. The 7.99 or so asking price is typically what you would pay if you could find the stuff locally; however, in Jackson you may have a little difficulty doing so. You could support your car and the site at the same time.

fly_S2K

In the Owner's manual it states that a temporary replacement fluid for honda MTF is motor oil with an equal weight of 10w-30. With that in mind, 75w-90 logically wouldn't be doing the tranny any good. The gear oil is much too heavy for the tranny. I really suggest just going the extra mile to pick up some Honda MTF, Redline MTF, Pennzoil/GM Syncromesh, or other MTF's that fits the right weight.
Hope that helps.

-Johnny

CoralDoc

Correct, with emphasis on TEMPORARY.

Quote:

With that in mind, 75w-90 logically wouldn't be doing the tranny any good. The gear oil is much too heavy for the tranny.

While this sounds like it should be true, it isn't. Gear oil and engine oil use different specifications for their weight (viscosity) ratings. For example, 75W/90 Mobil 1 gear oil has a viscosity index of 150, similar to the viscosity of a 10W/40 motor oil. However, you are correct that it is unsuitable, the additives in gear oilare different than in motor oil and gear oil should NOT be used in the transmission of the S2000.

Quote:

I really suggest just going the extra mile to pick up some Honda MTF, Redline MTF, Pennzoil/GM Syncromesh, or other MTF's that fits the right weight.

Good Advice. I use Honda HG manual transmission fluid. There are some exhaustive threads about this topic, do a search to read about other options and recommendations.

fly_S2K

Thnaks for clearing up what I left out or missed. Great information.

StwoK

True statement

Hypoid gear oil rated at GL-5 or GL-6 should be used only in the differential and it contains activated sulphur. The sulphur compound will corrode the brass synchros in your transmission over time , resulting in its failure. Use GL-4 rated oil your transmission.