Is it really necessary to change the trans. fluid at 30K miles? If not when should it be done? And is there some fluids better than others?

 

Nessesary, probobly not, useful yes. Search around for different brands. 30,000 is right around the corner for me and when I change it I'm going with Royal Purple tranny fluid, it seems to be a popular choice amongst users

 

+1 I highly recommend the Royal Purple for all your lubrication needs. I run it in everything on both my cars. Works great.

 

yes but you do pay a great price for royal purple...
for engine oil i bought Mobil 1 ... less costly but probably performs about the same...

 

Actually Royal Purple only costs about $1.00 more per Quart and it I have seen it dyno 7whp more then Mobile 1 with my own eyes. That is why I switched in the first place.

 

The topic is trans fluid and you are discussing engine oil??

Mobil does not offer a synthetic (Mobil 1) that they recommend for the 6MT in the Z.

 

where can i buy it? also, will they work with AT?

 

I recently switched mine to Redline MTL and MT-90 trans oil. Pretty much the same as Royal Purple. I can tell my tranny shifts much smoother and the 'notchiness’ has decreased.

I also recommend changing the diff fluid at the same time since the stock oil was very dirty when I changed mine; at 12k.

 

Bubble, here you go http://www.royalpurple.com/dealers/cab.html

Might want to call them up first because not all places carry the tranny fluid.

 

It's funny the Royal Purple Syn. gear oil with a 75-90 weight says it's okay of both GL-4 and GL-5 applications.....I know this has been done to death, but that doesn't make me feel to good about using the royal purple????

 

i have AT, after checking on their website, it said:

Max ATF® is recommended for all automatic transmissions requiring Ford Mercon® or GM Dexron® III transmission fluids.

so is nissan requires Ford Mercon® or GM Dexron®?

 

You will generally find this on all synthetics. On mineral based oil, GL-5 mixtures contained ingredients such as sulphur and other chemicals that were corrosive to certian metals. If you put mineral GL-5 in a box requiring GL-4, you had problems.

Synthetics such as Royal Purple have no natural ingredients and NO corrosive ingredients what so ever. That is why they work on GL-4 and GL-5 with the same formulation.

 

Good info...thanks!!!

 

I had the same concern and emailed royal purple, they pretty much said the same thing, and they guarteed that their gear oil meets or exceeds all standards and certifications.

Royal Purple
10-30 in the motor
Max Gear in the diff and tranny...

 

The Nissan 5AT takes a special fluid called type J or J-matic that is only available through them, nothing else can go in there!!!!!

 

I would change it just to be on the safe side.

 

I assume you mixed it 50/50, thats what they told me to do.

 

I got mine changed at 25k miles. It was a little dark so it was a good thing it was done. The Nissan matic J is required.

 

Thank you so much, that is the most straight-forward, informative answer I have found. BTW, people seem concerned about the price of RP, I bought Max Gear 75w90 on-line for $9 per quart, so it really isn't expensive at all. I bought it at www.rpmoil.com, if anyone is interested. Plan on putting it in both diff and tranny this weekend.

 

https://my350z.com/forum/engine-and-drivetrain/161182-5at-transmission-basics-info.html

"Nissan-Infiniti TSB (Technical Service Bulletin) addressing Nissan Matic-J fluid, the ATF flavor that's spec-ed for the G35/350Z.......

SERVICE INFORMATION

If the automatic transmission in the new Q45 (F50) or G35 (V35) requires service, a new type of
automatic transmission fluid MUST be used. The new fluid is Nissan Matic-J.
The New Nissan Matic-J
• Only Nissan Matic-J automatic transmission fluid (P/N 999MP-MTJ00P) is specially formulated to meet the
exacting requirements of Infiniti's new 5-speed automatic transmission (RE5R05A).
• The RE5R05A transmission contains new internal components that require the use of
Nissan Matic-J only!
CAUTION:
• Usage of Nissan Matic-D or any other automatic transmission fluid in the RE5R05A 5-speed automatic
transmission will cause deterioration in driveability and transmission durability.
• Do NOT use any other fluid for the RE5R05A 5-speed automatic transmission, only use Nissan Matic-J.
• Use of any other fluid may result in damage to the RE5R05A 5-speed automatic transmission, which will
not be covered by the INFINITI warranty......"