When to flush/replace fluids?

[consultant1027]

Picked up a used G37X with 43K miles on it. Had the dealer give it an inspection and had the front brakes service bulletin applied. They tried to sell me a $400 rear brake job and another $400+ in fluid flush/replace (wanted to do everything: radiator, transmission, differential/transfer case, brake fluid).

I know from experience at Volvo and Acura this is how dealers try to make money selling these overpriced services. I'm sure a lot of Infiniti owners have deep pockets and just trust the dealer and pay their crazy prices afraid their car won't work right if they don't follow what the dealer recommends to the tee.

I told the service rep that I reviewed the maintenance schedule for this car and I didn't see any of these things listed in the first 80K miles! (But I know they should eventually be done.) Only oil changes, inspections, and in-cabin filter replacement is what I've seen as the recommended scheduled maintenance up through 60K! They said they make this recommendation for preventative maintenance on a case by case basis. (Feels to me more like they're not selling enough new cars to make a profit and trying to make up for it elsewhere.) I think they even recommended a power steering fluid flush. It was a lot of stuff. I thought the new 7-speed was a 'sealed' system and you don't have to flush it like previous ATs or at least not nearly as often?

Out of all the fluid flush/replacements that can be done on the car. Which ones would people recommend as most necessary (do it sooner than later) and which ones are the easiest to do yourself?

[SVTCOBRA]

Had the transmission flushed at 45K on the 04 and and 40K on the 08.
Had the diff done of the 04 at 50K
I did the coolante on the 04 at 60K

I'll have the transfer case and diff done on the 08 at 50K (had it checked at 40K)
My local Nissan dealer did the transmission and diff....check them out and save some $$$

[telcoman]

New brakes and brake fluid 84968 miles
transmission flushed Not yet
The differential Not yet
Coolant replaced and flushed along with new plugs and belts at 106682 miles

Telcoman

[consultant1027]

You know, I was talking to my Dad about this subject. He's a car guy. He's owned 36 different cars in his life. Has drivin some of then to over 100K miles. He said in all his life, he did a brake fluid flush once and maybe a radiator coolant flush once. Nevey had any issues and over half his cars he bought used (with low miles). His opinion is that while there is some benefit to these flushes, how significant it is is anyone's guess. He sees the main benefit of these flushes is more peace of mind than actually having a major/significant benefit on the life of the car. Most people don't keep their cars long enough to every find out if the flush made a difference and they'd have to own an identical car without the flushes done to compare to! He said for those planning on driving their cars 'forever' (like 200K+ miles) then these fluid flushes will probably provide some benefit in that long timeframe.

He said a lot of people will argue about the importance of these flushes but he said here's what the final word should be. Who knows the car best as far as its maintenance needs? The manufacturer, the people who designed and tested and build the cars. If in the first 80K miles the owner's manual recommended scheduled service doesn't say to replace/flush any of these fluids, then there you have it. It isn't necessary. If it was, the manufacturer would recommend it, especially to avoid/reduce warranty claims.

But this type of question reminds me of the sort of topic like what's better 5W/30 or 10W/30 oil. Or Amsoil or Mobile 1. Or whatever. Us "car people" have built up deeply rooted opinions over the years, some based on actual experience, some based on gut feel, some base on just wanting to feel good about our cars and baby them knowing you've gone above and beyond the average call of duty for maintenance. I'm the babying type. If I were honest with myself, half the stuff I've done to my cars was probably money wasted - but it made me feel good that the car was cared for as best as possible. But I'm older now, hopefully wiser (or just think differently about things.) and I'm not some deep pocketed gullible owner that is going to fork out $500 in fluid changes when the manufacturer doesn't recommend doing so.

[telcoman]

You know, I was talking to my Dad about this subject. He's a car guy. He's owned 36 different cars in his life. Has drivin some of then to over 100K miles. He said in all his life, he did a brake fluid flush once and maybe a radiator coolant flush once. Nevey had any issues and over half his cars he bought used (with low miles). His opinion is that while there is some benefit to these flushes, how significant it is is anyone's guess. He sees the main benefit of these flushes is more peace of mind than actually having a major/significant benefit on the life of the car. Most people don't keep their cars long enough to every find out if the flush made a difference and they'd have to own an identical car without the flushes done to compare to! He said for those planning on driving their cars 'forever' (like 200K+ miles) then these fluid flushes will probably provide some benefit in that long timeframe.

He said a lot of people will argue about the importance of these flushes but he said here's what the final word should be. Who knows the car best as far as its maintenance needs? The manufacturer, the people who designed and tested and build the cars. If in the first 80K miles the owner's manual recommended scheduled service doesn't say to replace/flush any of these fluids, then there you have it. It isn't necessary. If it was, the manufacturer would recommend it, especially to avoid/reduce warranty claims.

But this type of question reminds me of the sort of topic like what's better 5W/30 or 10W/30 oil. Or Amsoil or Mobile 1. Or whatever. Us "car people" have built up deeply rooted opinions over the years, some based on actual experience, some based on gut feel, some base on just wanting to feel good about our cars and baby them knowing you've gone above and beyond the average call of duty for maintenance. I'm the babying type. If I were honest with myself, half the stuff I've done to my cars was probably money wasted - but it made me feel good that the car was cared for as best as possible. But I'm older now, hopefully wiser (or just think differently about things.) and I'm not some deep pocketed gullible owner that is going to fork out $500 in fluid changes when the manufacturer doesn't recommend doing so.

The auto manufactures recommend all kinds of things. Wiper blades before new ones are needed radiator caps, all kinds of fluid changes etc.
I have not had as many vehicles as your dad but I've been driving and owning vehicles for 50 years. Yes I'm an old farht
The most mileage put on a vehicle purchased brand new in 1980 was a diesel VW Rabbit whose oil pump failed at 246000 miles. Never changed differential or transmission fluid. Brake fluid gets replaced during brake jobs.
The only automatic transmission I owned was a 74 Mazda RX4 rotary engine. Put over 100k miles on it never changed transmission or differential fluid.
I do change oil and filter every 3 to 4k miles and just gave my G35 its 39th oil change.

Telcoman