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A few maintenance questions

11649 Views 7 Replies 6 Participants Last post by  cvipgo
Going through the manual, I came across the following:

1) The car has two air filters under the hood(you'll see their placement in the schematic of the engine bay). What is that second filter for?

2) The inverter fluid gets changed after 15 years/125,000 miles. What the heck is inverter fluid?

3) The coolant/antifreeze is good for 7 years/105,000 miles. Really? I thought it had to be changed way before then.

4) According to the maintenance booklet, the automatic transmission fluid NEVER needs to be checked. Even though it is obviously a closed system, I would think that it would need to be changed at some point. Anyone here with technical expertise who can explain?
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I think that just like the G it is a dual air intake system so there are two air filters.
I think that just like the G it is a dual air intake system so there are two air filters.
That must be a recent addition to Infiniti. I had a 2nd generation G(2007), and it had just the one air filter.
All fluid break down at some point in time. I would change it before the 105,000 miles. As for me, I will change it around 50k miles since I plan to keep the car for at least 10 years. My 2009 Lexus ES350 is the same. I got it change at the 50K miles. Cost me under $200 to change the transmission fluid. Even if it might not be necessary, but at least it buy me a peace of mind.

4) According to the maintenance booklet, the automatic transmission fluid NEVER needs to be checked. Even though it is obviously a closed system, I would think that it would need to be changed at some point. Anyone here with technical expertise who can explain?
Going through the manual, I came across the following:

1) The car has two air filters under the hood(you'll see their placement in the schematic of the engine bay). What is that second filter for?

2) The inverter fluid gets changed after 15 years/125,000 miles. What the heck is inverter fluid?

3) The coolant/antifreeze is good for 7 years/105,000 miles. Really? I thought it had to be changed way before then.

4) According to the maintenance booklet, the automatic transmission fluid NEVER needs to be checked. Even though it is obviously a closed system, I would think that it would need to be changed at some point. Anyone here with technical expertise who can explain?
1) One filter for each bank of cylinders
2) For cooling the hybrid batteries
3) No one is stopping you from changing it early
4) I plan to change it around 75k miles
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1) One filter for each bank of cylinders
2) For cooling the hybrid batteries
3) No one is stopping you from changing it early
4) I plan to change it around 75k miles
When did they start using the two air filters? As I said, my 2007 didn't have them.

Obviously I can change out the fluids early, but this is the first time I've ever seen such a long recommendation for coolant. When did this start?

And the same for the transmission fluid. When did they start saying that it never needed to be checked?

If these are new recommendations, then it seems that the drivetrain is more different than we thought.
Going through the manual, I came across the following:

1) The car has two air filters under the hood(you'll see their placement in the schematic of the engine bay). What is that second filter for?

2) The inverter fluid gets changed after 15 years/125,000 miles. What the heck is inverter fluid?

3) The coolant/antifreeze is good for 7 years/105,000 miles. Really? I thought it had to be changed way before then.

4) According to the maintenance booklet, the automatic transmission fluid NEVER needs to be checked. Even though it is obviously a closed system, I would think that it would need to be changed at some point. Anyone here with technical expertise who can explain?
The only thing I will add here is a caveat about the weird construction of the supplemental cooling system. I would strongly suggest against DIYing this one. And if it were mine I would probably just leave it for the 100K in all honesty, unless it degrades, I would probably test it starting at about 60K.

1) One filter for each bank of cylinders
2) For cooling the hybrid batteries
3) No one is stopping you from changing it early
4) I plan to change it around 75k miles
Perfectly worded answers. The only thing I would add to that is the inverter fluid mentioned here is part of a separate cooling system that is specifically designed to keep the item that steps up and controls the voltage for the drive motor running at its optimum temperature. This device has to potential to generate a ton of heat. The inverter operating temperature is lower than the engine so they have separated them now.

When did they start using the two air filters? As I said, my 2007 didn't have them.

Obviously I can change out the fluids early, but this is the first time I've ever seen such a long recommendation for coolant. When did this start?

And the same for the transmission fluid. When did they start saying that it never needed to be checked?

If these are new recommendations, then it seems that the drivetrain is more different than we thought.
The V36 sedan launched in 2007 used dual air filter with two throttles to improve throttle response as well as fixing the anemic feeling the earliest Gs suffered from under load. The 2007 coupe was the last model to have a single air filter (of the G line). The transmission fluid went to either long life or life long in 2009 when the RE7R07A transmission came out in the FX35/50.
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The V36 sedan launched in 2007 used dual air filter with two throttles to improve throttle response as well as fixing the anemic feeling the earliest Gs suffered from under load. The 2007 coupe was the last model to have a single air filter (of the G line).
True
I have a 2007 G35 sedan which has dual intake system (with two Air filters).
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