Had a question for anyone who knows exactly how hot the trans fluid gets for our manual transmissions in weather such as Arizona or even track conditions. The reason I'm asking because a lot of my GTR friends have experienced high temps in their DCT's and switched over to Wilall trans fluid rather than the OEM fluid along with an addition to a trans cooler such as the HKS or Greddy unit. I know I"m going to switch to synthetic Redline 75w85. Also, have any of you guys ran the Motul gear 300? It says on the bottle that it's gl4/gl5 and I know the gl5 will cause damage to our brass synchs. Just out of curiosity of people who experienced any sort of issues in hot weather and racing conditions? I plan on running a trans cooler and oil cooler soon, I just want to hear some feedback on what you guys have experienced. Thanks.

 

GTR trans and 6MT Z trans are completely different animals. A trans cooler is not need unless your running full race pace segments over 30 minutes long. A trans cooler will set you back a pretty penny, its around $400 for just the pump.

 

I understand that both cars are different. I'm just wondering if anyone out there experienced anything with high temps with our transmissions.

 

your crazy to run ANYTHING but oem NISSAN fluid in your trans.

lol..
With all this reading youre doing, im surprised you werent aware of that.

I have redline.. its terrible. Its extremely notchy, and has zip for detergents in it.


trans cooler for a stock Z tho??

 

I guess it's different for everyone. The OEM fluid is fine, but I just feel it would be better with something that can handle more heat. A lot of Nismo people tell me that Redline was the way to go especially in hot conditions. I don't know if your transmission that you ran that fluid with was a the CD09, I had a buddy on here who used to track his Nismo in Texas all the time and had no issues. With the GTR is a little bit more touchy with fluids as opposed to our transmissions. Stock, I'm planning too because who knows how hot our transmission fluid is getting and a peace of mind just like the oil cooler. It's HOT here man, you know that.

 

You already know that I'm building so I would do that for the sake of keeping things on the cool side. Obviosuly, when I step into the GTR it'll be the case here to modify those components.

 

pics or it didnt happen.

You deserve this.

 

I talked with a few vendors at ZDAYZ and all of them say the OEM fluid is junk and to switch to Redline.

 

Vendors don't sell OEM fluid (for the most part) so they're not going to sing it's praises.

Usually aftermaket stuff is good to go, but we have fussy transmissions, esp. with the older versions. There's something in the OEM fluid that makes them run nicely.

Also, you can't even come close to comparing the GTR box with the 6MT. That's an auto for starters, it's also AWD, not to mention about 600 brake. The requirements for those three items, even on their own, is far in excess of anything on the 350z.

No concerns is the short answer.

 

Let me rephrase that, builders/racers recommended it.

 

What kind of power level are you talking about, and how much tracking are you going to be doing? Depending on your answer to this, there actually may be some benefit to you running a GL5 oil even though the trans is specced for GL4. GL5 oil has far superior bearing and gear face lubrication properties to GL4 and will protect those parts better. The trade off is that synchro action can suffer (which is a definite consideration with this trans especially, because of the synchronizer problems it is known to have). Those same EP additives that make it so good for bearings and gears, cause synchronizers to have trouble synchronizing (meaning you might end up with gears grinding, and excessive wear on sleeves and the synchro teeth and engagement teeth on the gears).

The notion that "anything but OEM is a bad idea" is incorrect. Redline (and many other) trans oils are quality products that benefits over OEM especially in race conditions. Redline is the name you hear most often because it is the most well known and one of the easiest to come by of the "really good" group.

But previous posters are right that you cannot compare the GTR transmission and the Z transmission in any way.

You say you plan on getting a trans cooler. Do you mean you are actually planning on tapping fittings, and installing a pump too? I assume you know you can't just plop a trans cooler on a manual trans like you can on an automatic trans which already has a pump and fittings built in, right?

 

Er, the problem with the GL5 is that it contains sulphurs that 'eat' the soft 'yellow' metals on the synchs, don't do it.

 

That is a distant secondary consideration, a typical argument brought up by people who have no first hand knowledge building manual race transmissions. You will wear out the synchros in a car that is road raced (especially a trans that is hard on synchros like the 350Z trans) long before you "eat" them away. The "eating away" of yellow metal synchros by GL5 will take years.

I built race transmissions for 5 years at a very high level, transmissions I built and modified have been in many championship winning and record setting road race, drag race, and bonneville salt flat cars. I know what I'm talking about when it comes to this stuff.

 

So, are you trying to say what i said is wrong? because that's what it looks like.

 

I am saying exactly what I said. the corrosion consideration is a distant second to the synchronizer function problems that can sometimes be had with GL5 in a GL4 specced transmission, and can also be outweighed by the benefits of GL5 in certain applications (like a car that is tracked a lot). Which is why I asked him how much racing he'd be doing with it and how much power he is making, etc.

Also there is the fact that most GL5 oil manufacturers use deactivated suphur compounds these days that offer a much lower corrosion risk to yellow metals than they did 10 or 20 years ago, but I didn't even bother to go into that.

In short, if you are racing the car often enough and hard enough you are going to wear out other components in the transmission long before you do any appreciable corrosive damage with GL5 fluid.

 

GL-4: BECAUSE STREET CAR
GL-5: BECAUSE RACE CAR

Race car means deep pockets with backup cd009 on hand, spare motor, clutch/flywheel and 30k cash reserve