Change your manual transmission fluid ASAP!!!

[Scooby South]

Getting ready to do this on my car. along with a new LSD...

Bill

[FrSleeper]

So has anyone experienced problems with using a GL-4 synthetic trans fluid???

[roddy]

No. Most manual trans fluids are GL-4. GL-3 is actually an obsolete spec and hard to find. GL-5 is the one you want to avoid for use in the transmission.

[brad fischer]

Someone asked what other cars had a similar Aisin transmission. The Genesis Coupe has a Aisin as well and has most of the same issues that I read hear. I have a 2010 Genisis bought in 2009 and a BRZ bought in 2013. 2nd gear cold shift difficult and occasional grind upshift to 2nd.

[JB86'd]

Originally Posted by roddy

No. Most manual trans fluids are GL-4. GL-3 is actually an obsolete spec and hard to find. GL-5 is the one you want to avoid for use in the transmission.

The exception to that is motul 300..which is gl-5 and gl-4

[solidONE]

Originally Posted by rice_classic

By the way, because of our awesome engine bay, you all realized that you can fill your tranny with a tube and funnel from above the car right?

Of course you did... using a pump from underneath the car would be silly. :wink:

Originally Posted by Kostamojen

I filled with a tube from the top. But I still had to lift the car to drain it and get the plugs off and the skidplates off, all that jazz.

What diameter OD tube to fit the fill hole?

[roddy]

Originally Posted by JB86'd

The exception to that is motul 300..which is gl-5 and gl-4

You're right, there are a few that have GL-4 and GL-5 ratings on the label. I should have mentioned that. My point though was to not use a full on GL-5 in the transmission.

[funbeatsfast]

I replaced the factory transmission oil at 5K miles. It was brown with a few shavings, but nothing that alarmed me. Put in Redline MTF. That felt a little better, but still had to 1-2 shift deliberately.
Of course I filled it from below, because I love pushing heavy oils through a fluid transfer pump for 30 minutes. Definitely not because I'm an idiot...
I read about Motocraft fluid on one of these threads, and remembered hearing about it from a Miata guy. I work for a Ford franchise, so decided I should give it a try. At 11K (early May) I put in 2.5 quarts of Motocraft XT-M5-QS GL-4. Cost $17 per qt with employee discount. Twenty something without.
It's awesome. Borderline magical. In less than a mile I could tell it was better than Redline MTF. Two auto crosses later it still feels great. In 5K more miles I'll buy 3 more qts of this stuff. I might buy them tomorrow just to have on hand. You should all go out and buy some too.

[Rocket.BRZ]

Hey guys I wanted to update that I switch from pentosin to redline with 1 quart of shockproof. 5th gear grind is completely gone and its shifts like butter.

[White64Goat]

Which Redline products specifically? There are several in the trans fluid line and the Shockproof line. Thanks

[Rocket.BRZ]

Originally Posted by Rocket.BRZ

Hey guys I wanted to update that I switch from pentosin to redline with 1 quart of shockproof. 5th gear grind is completely gone and its shifts like butter.

it was 75W90 NS GL-5 redline gear oil with 1 quart of lightweight shockproof.


fixed 2nd gear grind and my 5th to 6th grind. Shifts like butter much better than pentosin which was my last fluid.


(updated for more info)

[Rocket.BRZ]

Originally Posted by White64Goat

Which Redline products specifically? There are several in the trans fluid line and the Shockproof line. Thanks

reply to your post is above.

[OICU812]

Originally Posted by Rocket.BRZ

it was 75W90 NS GL-5 redline gear oil with 1 quart of lightweight shockproof.


fixed 2nd gear grind and my 5th to 6th grind. Shifts like butter much better than pentosin which was my last fluid.


(updated for more info)

... so basically 40% of your tranny fluid is shockproof product correct?? Curious why you did this or rather how you came up with idea on the blend? Not too familiar with shockproof from RL and it's safe margins..

[xxBrun0xx]

Originally Posted by Rocket.BRZ

it was 75W90 NS GL-5 redline gear oil with 1 quart of lightweight shockproof.


fixed 2nd gear grind and my 5th to 6th grind. Shifts like butter much better than pentosin which was my last fluid.


(updated for more info)

Isn't GL-5 the one that's bad for our tranny? Even if it seems to work, wouldn't it void your transmission warranty, since Subaru/Toyota only recommends GL-4?