I got the autotranny replaced 1 1/2 years ago by Nissan. Well thinking of circulating the ATF to get the fine and shaving out before swithcing to synthetic ATF. The old dealer used a flushing machine. Well moving to Oakland CA area, the dealers have a puzzled look on their faces when asked to replace the ATF with synthetic and asked
if they use a pumping machine. Three of them have said that they just remove the bottom pan and replace the screen, leaving about a quart behind. It's my understanding that the Nissan tranny's screen is on top (thus not easily replaced)
and there no drain pan nor plug. Have Nissian changed design?

 

I think it is in the top where the Valve Body is located.

 

there is no drain pan on our trannies.

what they'll need to do is hook it up to a flushing machine and do it that way. You'll need about 12 quarts of fluid to do the job, so be ready for fork over the $$ when you have it done.

 

aww crap, i was thinking about having this done too.. how important is changing the tranny fluid? whats better for the money changing the fluid or geting a tranny cooler.

 

Well it depends how long it's been since you've changed the tranny fluid. If a long time, then I would say go ahead and do that. If it wasn't too long ago, then I would say get the cooler installed and then change to synthetic (which is my next step).

My siutation: Installed tranny cooler and changed the fluid (regular Dexron III) about 3000 miles/3 months ago. Now the tranny is beginning to shift not as smooth (colder weather?). Should I flush and fill with synthetic at a shop? Or can I just change to synthetic by changing the fluid gradually over 2 or 3 weeks time?

Thanks in advance.

 

You don't need a machine to do a fluid exchange. (It's a DIY job. Just do a search.)
The red dye in ATF is temp sensitive. If it changes color (to brown, or darker) the fluid has been overheated and should be changed. Synthetic ATF can operate at a larger temp range than regular ATF. However, even if the synthetic fluid is ok at high temps, other soft parts like the adhesive on the friction material and seals can still be damaged from excessive heat. The item that generates the heat is the torque converter when it slips. If you do things like race by engine braking to stall speed, or sit in heavy traffic during the summer with the AC on, you also need a cooler.

 

Tranny cooler or not to tranny cooler. I've been told by realiable sources that with a tranny cooler, cold weather shifts are harder and it takes much longer for the tranny to reach proper operational temp. Good for hot and heavy load, but not very good for normal cold weather driving.

The Nissan auto tranny was designed to run on Dex IIe, which is thicker than Dex III. Dex III is thicker than synthetic ATF. Is switching to syn. making it too thin? Is using high grade (truck grade) Dex IIe better than synthetic?

As far a I know, I got a new not rebuilt tranny. Someone posted a notice than Nissan doesn't sell new ones anymore. My tranny went because of a side collision into the front wheel. Luckly no one was hurt.

 

There's been a lot of talk that Nissan tranny are sensitive. That goes against the old experience that they were work horses and last 160 K mile or more. What happened? Change of design, mfg. or the switching to Dex III in a tranny that was designed for Dex II?

Let's hear it from the high mileage Max. tranny (with no rebuilt) owners. Are you using Dex II or III or synthetic? Low mileage ones, what are you using? Any trends?

Dave

 

Nissan tries to use the fewest different types of trans in the most number of cars as possible. So some applications work better than others. The same basic transmission used with the VG engined Max's was also used in the Stanza and M30 Infiniti. They last a lot long in a Stanza. The 4th gen Max's use the same basic trans as the Q45; they hold up fine and die around 100k in the Q.
The trans had no problem getting through the warranty period (even with an extended warranty) so Nissan probably wasn't all that concerned. Now all these cars are old, didn't have their fluid changed often enough and are beat on. The trannies die. If an owner started out on day one with the intention of keeping the for 10+ years/200k miles, they would have had to have changed the fluid (complete exchange) every 30k miles and put on a cooler.
There's a guy on the Yahoo Infiniti board that is part owner of a Infiniti repair place. After seeing 100's of cars (Nissans) he's come to the conclusion that you can double the life of a trans by putting on a cooler and changing the fluid.

 

I'm about to reveal my former state of ignorance so be gentle with me. I didn't know you should change tranny fluid once a year... I bought my 89 GXE with 27,000 miles on it and I got 170,000+ miles out of the transmission (original fluid for all 170,000+ miles). I paid $2500 to have it rebuilt so I'm real motivated now to take good care of the tranny.

 

A friend asked a tranny shop to change his fluid because his tranny was acting up. The shop said that the cruddy fluid was all that was holding it together, i.e., change the fluid and the tranny will quit. After a few years, he's still using the same tranny.

I know a couple of tranny's that have quit right after fluid changes. But the thought is to get the fluid changed, before it's too late.

 

This is true...every mechanic has told me that if the fluid has not been changed in a long enough time, it forms an addiction to the metals that float around in the fluid and they begin to fill in the parts of the tranny that have been eaten away. so when the tranny is flushed, those gaps reopen and nothing is aligned correctly and you arent moving that car until rehab. time.
moral of story...communicate with tranny shop clearly so that they know what they are doing (ie. they mention that addiction to you and understand the consequences) and what you want them to do to the tranny specifically.