I usually have the service on our G37x sedan done by the dealer. Whenever we go in I tell them exactly what I want done instead of saying "do the 30k mile service, etc..." because I know a lot of those little visual checks and inspections can add up to $$$. I have a copy of the manual on my computer and cannot find any mention of changing the transmission fluid, transfer case fluid, or the differential fluids. Obviously they need to be done at some point, but when? The car just turned over to 30,000 miles and there are no issues at all with it. I don't ever recall changing transmission fluid that early. On our Tahoe we MIGHT have changed it once in 100,000 miles, and some people say don't ever change it. Just looking for some feedback on when do to these fluids. Thanks!

EDIT: Just found one answer..."7-speed automatic transmission fluid is maintenance-free." Also see the other fluids as a "premium service upgrade" every 30,000 miles. Fine, but when does it NEED to be done?

 

Try searching the forum. The trans fluid is not a lifetime item. It should be replaced periodically. How often is a good question. Much depends on how aggressively you drive the car. I'd say somewhere between 30-50K would be a reasonable range.

 

For whatever reason Infiniti is very vague when it comes to service of the AT. The manual for my 09 doesn't list any AT servicing unless you're following the top "extreme use" schedule. Some dealers will say it's a sealed transmission that doesn't require service (which is total BS), some will say you need to service every 30k miles, which is a bit on the early side, and some in the 70-80k mile range. I changed mine (did the DIY procedure on the site) which is a 3x drain & fill & a pan removal which allows you to clean the pan & magnet residue. Some dealers will just do a simple 1x drain & fill, and this at every 30k may be a viable plan. IMO if you wait until 70-80k miles you should do the full 3x drain & fill and a pan cleaning. Just be sure when inquiring to find out exactly what the dealer does when giving you a quote for any AT servicing. Here's the on site DIY for reference~https://www.myg37.com/forums/d-i-y-i...rop-clean.html

 

Thanks for that. We won't have the car past 50,000 miles, will probably be trading in for a CPO Q50 next summer or the summer after that. Any info on the differential fluids or transfer case?

 

It's a good idea to change the transmission fluid every 30-60k depending on driving habits and weather conditions.

I personally had my transmission fluid changed (drain and fill) at the dealer at 40k, and did the differential fluid myself at 30k. I would treat the transfer case similarly to the differential fluid - would not hurt to change it every 30-45k.

If you're planning to only keep the car til 50k, you could probably do without. There are many who have do not change the transmission, differential, and transfer case for quite a while (60-100k).