New Owner - Questions

[ArmedAviator]

Hello everybody!

I am a first-time Infiniti owner. Infact, a first-time anything-other-than-Ford buyer. Today I bought a used 2012 M37x in Black Obsidian with 84,000 miles on the clock. It appears to be in good shape, but I have some questions so I can make sure she's tip-top.

1. Do the 2012 models need the ECM to be flashed for the 7AT shifting issues?
2. Is there a software update for the nav/radio on the 2012s to fix issues with Bluetooth being funky? (I remember reading something about it, but forget the years).
3. Is your brake pedal squishy? Mine is and I'm not sure if it's normal for this car or if it's in need of a brake bleed - the brake master cylinder reservoir has fresh clean fluid in it so maybe there's air in it. Is Pennzoil or similar DOT 4 synthetic okay? Recommendations? Any gotchas with flushing with the ABS?
4. At 84k miles, should I assume all other fluids and filters (except engine oil) are old and replace them all? (ATF, Power Steering, Coolant) Again, any gotchas with the replacement of these fluids?
5. Suspension - I'm not sure if it's because it's at 84k, but the suspension feels softer than I expected...but I mostly test drove Gs. How often do shocks/springs need replacing?
6. What things should I check to make sure they're up to snuff that commonly go bad or wear?

I am coming from a 2006 Mercury Grand Marquis that I put alot of work into for a quality audio system that looked near-stock, modified and tuned the engine and transmission, stiffened the suspension, and upped the rear axle ratio from 2.73 to 3.73 with a LSD. Was fun to corner fast and get two tire fires at stop lights. Sorry to see it go thanks to the fault of another moron on the road...

[Ilya]

Welcome to the forum (and Infiniti)!

1) Your best bet is to see if your VIN is applicable to that TSB. Ask your service advisor.
2) I know there was BT update on the Y50 (they moved the mic), but not sure about the Y51.
3) Mine is not any squishier than any other car I've ever driven, so if there is new fluid perhaps it was just changed and as you guess it there is air in the system. I'd definitely recommend a bleed before going further. Any DOT4 fluid is fine I believe. No issues with the ABS system if done properly.
4) Yes, I would replace them. Personally, I go to the dealer for all fluids that aren't engine oil. Just too messy and time consuming to do myself although I have the tools and lift in my garage to do it. Runs me about $650 to do coolant, transmission, and both front/rear differential.
5) You're at the point where you could use a suspension update (new struts and possibly things like sway bar links, etc.)
6) These cars are generally pretty reliable if you take care of it. Check the suspension and make sure your car is balanced/aligned and then the fluids...otherwise it should last you with minimal care so long as you keep up on the maintenance. It does happen, but rarely, that an M will be a 'problem child'. We had one member here who's brand new M had to get completely replaced with a new one because of a brake issue that was unsolvable.

[ArmedAviator]

Thanks for your feedback, Ilya.

Cash is tight at the moment since I dug deep into my savings account to buy this car even after the insurance check over my totalled car. Because of this, I want to do as much as I can by myself such as fluid changes and filters.

As far as the struts, I've only ever had separate shocks and springs on a car. Is it normal to replace the entire assembly or disassemble it and just replace the shocks? I.e. if I go to the parts department, what part number(s) should be ordered?

Is it possible to put Sport suspension on the AWD model? What parts would need changing to make it meet that criteria? Struts? Sway bars?

Thank again.

[Ilya]

For stuff like struts, I'd first check your local parts stores like Napa, Advance Auto, etc...the dealer will be pricey. If you do choose to go the dealer route, I use websites like infinitipartsusa.com to look at the parts diagrams to get the part numbers of parts I need. I sometimes will then even go on Ebay to buy the stuff as a LOT of dealers sell on there (you'd be surprised). It's legit OEM dealer parts usually at a better price than what they have in their actual parts department.

I don't remember what the Y51 is, but I know the Y50 had an all-in-one front setup and a separate rear setup (shock/spring separate). Any place you buy new shocks from whether it's OEM or aftermarket will sell you just the shock...you'll have to use spring compressors to get your old spring off the old shock and put it on the new one. Or, you can save up the money like many of us and get coilovers (BC is the most commonly purchased brand although since you have a V6 you have a few more options than us V8 guys) which are shipped to you, brand new, as all-in-one pieces with their own springs, etc.

I don't think anyone has tried, but based on my previous history with the Y50 (2006-2010), there is no way you can install RWD parts on an AWD car...

[Debonair]

#1 -Is it normal to replace the entire assembly or disassemble it and just replace the shocks? I.e. if I go to the parts department, what part number(s) should be ordered?

#2 - Is it possible to put Sport suspension on the AWD model? What parts would need changing to make it meet that criteria? Struts? Sway bars?

#1 - You only need to replace the struts if you are looking to keep the ride feel and height the same. The strut and spring assembly have to be removed from the car, the spring compressed, and then the strut changed. You can even take them out and have a shop compress the springs and swap the struts if you want and then you can just throw them back in. You can see a great DIY of the job HERE.

Your springs, even at 84K should be fine IMO. The car is not used for heavy loads or towing so they really do not get worn out too much.

#2 - As far as I know the only suspension difference on the S models versus the non-S models is a set of stiffer springs. I see no reason why you could not install a set of take-off S-model springs. It would just be a matter of finding them.

An aftermarket set of lowering springs and new struts, or a set of adjustable struts are may be an easier and cheaper route. With the springs+struts you get a fixed stiffness increase and lowering amount. With the adjustable struts (most of them) you can adjust the dampening up to 30 levels (they have a knob on them) and with all of them you can adjust the ride height from about stock to very low, and everything in between.

[ArmedAviator]

#1 - You only need to replace the struts if you are looking to keep the ride feel and height the same. The strut and spring assembly have to be removed from the car, the spring compressed, and then the strut changed. You can even take them out and have a shop compress the springs and swap the struts if you want and then you can just throw them back in. You can see a great DIY of the job HERE.

Your springs, even at 84K should be fine IMO. The car is not used for heavy loads or towing so they really do not get worn out too much.

#2 - As far as I know the only suspension difference on the S models versus the non-S models is a set of stiffer springs. I see no reason why you could not install a set of take-off S-model springs. It would just be a matter of finding them.

An aftermarket set of lowering springs and new struts, or a set of adjustable struts are may be an easier and cheaper route. With the springs+struts you get a fixed stiffness increase and lowering amount. With the adjustable struts (most of them) you can adjust the dampening up to 30 levels (they have a knob on them) and with all of them you can adjust the ride height from about stock to very low, and everything in between.

That's what I expected about the Sport struts. Perhaps I'll look for those. But if I was ust looking to stick with the original equipment parts on this X, what is a reasonable price to have a good mechanic or dealer do this? As I said, I've never dealt with struts and coilovers, so I'd rather just have them done professionally.

Next batch of questions.....

1. The coolant level in my car is low. I want to flush and fill it ASAP. That and the brakes I want to get done today, infact. Should I pay the price for Nissan Long Life (Blue) coolant from the dealer or is something from the parts store recommended and acceptable? For example, Peak Long Life 50/50 mix is available for $12/gallon a mile from my house. I believe I want to go with something that is silicate-free.

2. Any recommendations on air filters and cabin air filters? Go OEM or is Wix or Purolator Classic okay? I don't like K&N filters as they are not very efficient and have caused MAF sensor issues in the past.

3. What differential fluid brand/type/weight is recommended and how much is needed to flush and fill the AWD (I take it there's two diffs, but is there a transfer case that needs flushing too or is it part of the transmission)? It'll be a while before I get to this, so any place online is fine to order from. I couldn't find any writeups on the 37/56 series so want to be sure before I tackle it. A video of the M35 diff flush and fill looked pretty straight forward - use the drain and fill plugs as designed and you're done. (My Ford 8.8" required complete removal of the diff cover to change oil).

4. What oil types or brands, weights, and OCIs are commonly used by you folks? I've used solely Motorocraft filters and 5W-20 synthetic blend oil with 5,000 mile OCIs for over a decade now and that's all I know. I have a few gallons left of Motorcraft 5W-20 - is this acceptable to use in the M for 3-5k? I live in Ohio, FWIW. I change my oil every 6 months (fall and spring, when the weather is nice), and that keeps it around a 4,500 mile OCI.

In the mean time, I'm going to go clean my shiny new car's interior up a bit and learn what all the buttons do.

[Ilya]

1) I'd personally use OEM coolant...BUT, you can use ANY of the Japanese OEM fluids as they are all the same formula as far as I remember. In fact, in the Maxima world, many guys used Toyota (red) because it was the cheapest by the gallon. Honda (green), Nissan (blue), Toyota (red) are all fine. But that's just me. Since I have the dealer do it for me, mine is Nissan.

2) For engine air filters, I use Purolator from my local parts store. For the cabin air filter, I buy the charcoal one from Amazon. I have a HowTo in the FAQ on how to change the cabin one + the part linked (see my signature). You are correct on K&N filters being finnicky with Nissan/Infiniti MAF's. It killed my MAF on my 99 Maxima and I never used one again. I do have one on my motorcycle though as there is no such as MAF there.

3) Can't answer this as the dealer does this for me every 35-40kmi or so.

4) I have used AMSOIL, Castrol or Mobil 1 synthetic and prefer Mobil 1. I live in NY (please update your location in your profile with a general location so know you're from Ohio in future posts) and I use 0W-40 Mobil 1. For filter, I just use the NAPA Gold filters. I run my oil 5kmi which is overkill. I also put like 2 capfulls of Sea Foam in with each oil change to act as a cleaning agent.

[Debonair]

That's what I expected about the Sport struts. Perhaps I'll look for those. But if I was ust looking to stick with the original equipment parts on this X, what is a reasonable price to have a good mechanic or dealer do this? As I said, I've never dealt with struts and coilovers, so I'd rather just have them done professionally.

$300-400 with alignment sounds about right to me. Depends on the shop.

1. Should I pay the price for Nissan Long Life (Blue) coolant from the dealer or is something from the parts store recommended and acceptable?

2. Any recommendations on air filters and cabin air filters? (Fram, Wix)

3. differential fluid brand/type/weight is recommended and how much is needed to flush and fill the AWD

4. What oil types or brands, weights, and OCIs are commonly used by you folks? Motorcraft 5W-20 - is this acceptable to use in the M for 3-5k?

#1 - Have you checked the price on the OE coolant? I doubt the cost difference is enough to warranty going with the aftermarket stuff.

#2 - Either or will work fine

#3 - OE fluid or a quality Sythetic (Redline, Amsoil, etc.). For capacity go here: M37/M56/Q70 HowTo & FAQs > FACTORY SERVICE MANUALS (FSM) > 2012 > 2012 M > MA

#4 - I use Mobil 1 full synthetic most of the time but will run Castrol FS, or Quaker FS if they are on sale for a smoking deal. I run 5W30 only.

[ArmedAviator]

Good call on calling the dealer. Wasn't too expensive. $22/gallon. I got 3 gallons and will be changing that tonight.

I bled the brakes. The pedal feels slightly firmer but I'm not confident that it's where it should be. It does stop on a dime though. The rear rotors and pads need replaced.

I'll ask the remainder of my questions (more keep coming up) in separate threads to make it easier for others to find useful.