Thats interesting to know. I just got off the phone with Nissan yesterday who told me they don't do transmission drain and fills, they hook the car up to a machine with an external pump and run new fluid through the transmission (aka. tranny flush). My friend was going to go there for a tranny service and told him to go to his mechanic for a drain and fill, and save his transmission. (80k+ miles on his Maxima)

 

I did mine around 65k, im at 80k now, but i guess it felt a tad bit smoother or maybe its just wishful thinking

 

Did mine the other day at 67k, seems much better now.

 

mrtrodonet, it would be nice if you'd let us know what you ended up doing and the results. We can go by what Nissan recommends but in a case like yours knowing how the trans service worked your input would be of great value. Just in case we have someone else that neglects to change their fluids for a gazillion miles....
Gary

 

you cant flush out atf on the g's. you will have problems. Drain and fill would be the most advisable. will do mine soon at 125k, and i had friends that done a drain and fill on their g's 03-06 and had no issue.

 

Nissan recommends not doing a flush, that must really **** off the "Stealerships" that charge $300 to do that job! For those members that haven't changed there trans fluid until they get close to 100K miles I'd be interested to know the results of a drain & fill just for future members knowledge....Gary

 

What ATF are most of you using?

 

At 230k miles, I have no idea if the PO every drained and refilled the 5AT on my car. I would assume, having that many miles on her, he did it at least once or twice. But I could be wrong.

The tranny still feels snappy, and has nice, clean shifts when in taptronics mode. The only thing I do notice is a 2nd to 3rd gear clunk under heavy acceleration, but I'm pretty sure I've read somewhere that that's a fairly common issue with 5AT G's and Z's. So I'm a bit leery about actually doing it.

I may do a partial drain/fill and see how that goes. If I do, I'll report back to everyone, especially since my car is so high in mileage.

 

Pretty sure Nissan says that you NEED to use the Matic J fluid in the 5AT. In something as expensive and hard to repair as an auto tranny, I wouldn't use anything else, personally.

It's not something like a rear end, where if you blow it up, it's only a two or so hour job to fix.

 

Matic J was discontinued, although some dealerships still have it, Matic S is what you should be putting in now. It can be added to a transmission that has Matic J already in it, so using it for a drain and fill should be no problem, from what I've read.

I'm at 120k miles, bought the car at 60k miles and not sure of the transmission change history. Never did a drain and fill as I've learned from the past that a high mileage transmission should be left alone.

Unfortuantly, I sprang a leak in BOTH hard lines from the transmission to the cooler, so they had to be replaced. Checked the fluid before hand and it was a clearish red, and showed up as a dark rust color on my rag. I decided to drop the pan out and clean off the magnets for the install/drain and fill...to my surprise, the magnets were completely clean! Filled up with 5 litres of Matic S and after did notice the tranny feels "firmer", and the odd hesitation, not a slip, just a hesitation with random shifts, has gone away (possibly due to the leak or degrading fluid?)

I should add that my daily commute is 90+% highway, and I do baby the car with the exception of a few spirited driving moments.

 

2>3rd clunk is normal, it has to do with the clearance between the direct clutch and the hi-low-Reverse clutch

 

I may be missing something: is there somewhere in this thread where someone mentions what car/trans we're discussing? The fluid situation is rather different from the 5 speeds to the 7 speeds.

 

^ We are talking about the 5AT

Whats different about the 7AT?

 

The official Infiniti line is that the 7AT is a sealed unit and does not require fluid replenishment or replacement. Although there is a drain/refill procedure in the service manual.

 

That's what I thought. It was just a little unnerving the first few times I heard it, because it reminded me of how the tranny on my Trans Am used to clunk right before it blew up.