Changing manual transmission fluid
 

Hey guys, When I shift into 2nd gear, it feels rough sometimes. Something to do with my snycros?(sp) It just isn't as smooth as all the other gears. Will a transmission fluid change help? IS there a DIY on changing the fluid? I searched and couldn't find anything. IF there isn't can you guys tell me what kind of fluid and how to do it?
Thanks

Try doing the clutch res. fluid pump. That would help with clutch chitter sound and yes tranny fluid should be pumped/flushed out after 50k miles.

Yep, changing the clutch fluid will help - did the same on mine and there was a big difference. You can use dot 3 or even better, dot 4 or dot 5.1 (they last longer, absorb less moisture, and work better at higher temperatures). Don't use dot 5 as it's silicone based and you can't mix the two.

I have checked with several mechanics I trust and they all say unless you're redoing the clutch or working on the tranny, changing the transmission fluid is not totally necessary on a manual. The same is not true for auto's since there's higher pressures, etc and the fluid breaks down much sooner.

I haven't changed the tranny fluid myself but I've read you need a hand pump to refill which can be a pain. Be sure you know how to fill it before you drain it, or you'll be looking at towing your car to have it refilled... clutch fluid is simpler - do you have the FSM? Note that it's the same stuff as brake fluid so it's corrosive (wash it off paint immediately) and poisonous.

Ultimately, if you're not comfortable leaving the old tranny fluid in, there's certainly no harm in changing it out - it's not that expensive to do either.

Hope this helps and GL.

Changing your MT fluid if it's never been changed will help how your trans shifts if you use REDLINE synthetic trans fluid. Find an autoparts store that sells Redline, take it to any mechanic cost will be minimal....Gary

Don't take this word for word as spoken gospel. Some people have had problems with using other gear oils aside from the OEM Nissan/Infiniti manual transmission gear oil. The recommended viscosity of the gear our for our transmissions is a very odd one that's sort-of in between the two common viscosity levels that oil manufacturers typical make for gear oil.

Personally, I opted to just completely avoid taking any risks with this (since our transmissions are known to be finicky about gear oil), and went to the Nissan dealership and bought 3 quarts (I think that's what was needed) to fill my trans with new gear oil after doing my oil change at around 20K miles. I believe our transmissions take something like 2.2 or 2.5 quarts to fill them, but it's been a very long time since I changed it and I could be mistaken about that volume.

I've used Redline before in my Tacoma (a vehicle that is very not-picky about tranny oil) and it was fine for about 5000 to 8000 miles, and then it started getting hard to shift. I did a little research and found that a lot of people have run into problems with Redline gear oil in transmissions shearing prematurely and resulting in labored shifting. I personally experienced this, and switched to Amsoil gear oil in the tranny on my truck and the problem went away immediately and never came back.

If you do opt to buy the OEM gear oil for your G35 (which I personally recommend), don't buy it at Infiniiti... go to Nissan and buy it there. The Nissan gear oil is the same stuff as the Infiniti oil but it's like 3 or 4 dollars per quart cheaper.

i learned the hard way, when it comes to transmissions. You want reliability. In this sense i would stick with OEM fluid. Also what year g35 do you have? 03-04 and early 05 are known to have crappy manual transmissions. It usually 3rd and 5th gear that grind. They upgraded the syncros in late 05-07 models so there no more grinds.

If you dont have cd009 transmission, it will eventually get worst. changing the transmission fluid will help with the grinds but not eliminate it.

I changed my trains fluid with oem Nissan fluid and Redline gear oil in the diff.

My transmission literally has thousands, yes thousands of passes at the strip and I have no grinds.

Mine is a late 05 model.

I'm at 62,000 miles on my 04 right now. No grinds or anything, but it is a little rough. I'm thinking I need a transmission oil change and diff change though.

Thanks for the feedback guys. I have an 03. Only my 2nd gear is giving me problems and I am thinking about selling it soon. I want it to be perfect when I sell it. Do I need a pump or something someone talked about? How do I get the new oil back in?
Thanks

You don't need a pump, but it's well worth buying one. They're only like 4 or 5 bucks for a little cheap plastic hand pump that mounts to the top of the gear oil bottle(sorta like a liquid hand-soap dispenser). If you don't use a pump, you can gravity feed the fluid into the tranny by using a long hose and feeding it in from the engine bay. The purchase price of the extra length of hose to gravity feed it will cost just as much, if not more, than buying one of those pumps though.. and you're likely to spill gear oil everywhere in the process once it reaches capacity.

Trust me, buy the hand pump. You'll use it again at some point filling a differential or future transmission.

ummm....don't try to engineer science and stick with OEM....if you want to swap out transmission down the road then start experimenting with different brands. The OEM fluid lasted this long do you really want to gamble. Your transmission is junk anways no offense and being 2003-2004 it is lower than cd009. Cd009 started in 07/04 for 350z and towards the start of the year in 2005 for g35. My vehicle was build date 06/05 and has cd009. Get underneath and start taking picture of the bell housing from up and over and snap the top of the bell housing. CD009 has triple cone 1st, 2nd and 3rd gear syncro, 3rd gear baulk ring,5th gear baulk ring, and 5th gear

http://my350z.com/forum/engine-and-d...sion-list.html
http://www.350z-tech.com/forums/148-...rd-gear-2.html


Edit while you are at it look into the RJM A.F.P bracket to help with shifting, bucking, and jerking. The bracket, along with clutch fluid flush and new tranny drain and fill is the best solution until your tranny totally craps out or a new clutch which ever comes first.



BRACKET.....FTW

http://rjmperformance.com/

http://i124.photobucket.com/albums/p...DSC00087-2.jpg

When you have money down the road buy this setup...you will probably need a different shift fork and pivot ball the shorter one..thats what she said..d.erp

Tranny..click it u know u like tranny

http://www.z1motorsports.com/350_g35...oducts_id=3342

Clutch kit

https://g35driver.com/forums/engine-...hipping-5.html

https://g35driver.com/forums/g35-sed...pics-vids.html

http://i124.photobucket.com/albums/p.../MoneyShot.jpg

http://www.harborfreight.com/multi-u...ump-66418.html

http://www.harborfreight.com/oil-suction-gun-95468.html



http://mgaguru.com/mgtech/tools/pics/oil_gun.jpg


http://www.harborfreight.com/media/c...mage_16308.jpg

http://i33.tinypic.com/2hs2ej7.jpg

Sorry for jacking the thread, but..when should I change the MTF? I'm at 68k and I don't think the previous owner changed it before..