hexotic

You're correct on the oil changes. 5-7500 is good. As for flushing fluids. You can do the diffs, you can do the transfer case. Transmission, the dealership will refuse to do. They call it lifetime fluid. Basically there are clutch packs inside this transmission that wear down and clutch material is suspended in trans fluid. Doing a flush beyond 70k gets rid of that clutch material – not recommended as the transmission may start slipping. You can do a drain and fill, but not a complete flush. If the car is above 100k, don't touch the fluid, leave it as is.

killcount001

I’m guessing you suggest the diffs and transfer case but do you think I should do the trans drain and fill or not? It’s a little rough at the higher rpm’s when it shifts but I’m guessing that’s normal

socketz67

Personally, I feel that the OEM rear spoiler, midnight grill and front lip are mandatory cosmetic mods as they transform the look of the car quickly while maintaining a more modern upscale OEM look; a color matched roof spoiler (eBay) would be fourth.

Rochester

iTrader: (9)

The exact recommendations should come from the manufacturer for the car.

Conventional wisdom is to change standard oil every 3500 miles, and synthetic every 7000 miles.

Also at least once a year, because oil does break down over time, although synthetic less than dino.

I'm actually changing my oil today. It's been a year and a half since my last oil change, but only 3000 miles, so... whatever.

socketz67

I fall into the same camp Rochester. I change every 2.8-3K simply because its been 6 months or more since the last change.

v2vq

@killcount

worth checking this sticky thread below!

https://www.myg37.com/forums/newbie-...read-this.html

Phewwwwww, I learned the hard way when I bought my first car (2+2 Z32). Went straight to mods, neglected what needed to be maintained and lost a lot of money. Invest in your investment and the G will treat you right!

hexotic

I did it on mine at 74k miles, runs perfect. It's hard to give a straight answer since it may differ a bit from car to car and how much it has been abused or not. If you're in the 70-90k mile range, it's a good time to do it because doing it beyond that could have negative effects. That's about all I can say and you have to make the decision based on your situation.

P.S. the AT in the G does not like hard launches from stand still. Roll pulls are fine, but from a dig, would not recommend doing it too often. I'm on my second transmission, just saying lol

Atowsley

The first mod on my 2nd G37 (bought today) is to have the engine hoses replaced entirely with Z1 Silicone ones. The back heater one has a plastic clip that starts decaying. Mine also were bulging a bit at 60,000 miles.

Atowsley

My dealer when asked changed my transmission fluid (drain and fill). I'm not sure if there is an easy way to check? They accepted the work and charged me for it.

bigwillyvert

personally i would start with the things that will help your car handle the power first. good tires, coilovers, sway bars, subframe bushing collars, engine mounts, tranny mount, diff brace, etc. These cars were "luxury" vehicles so they have a lot of soft creature comforts built in for a smooth ride. These will all make your car handle much better and feel faster. Once those are done then go on and add power, but if you are serious about making jam honestly i'd skip all the bolt ons and just go straight to forced induction.

goldbug

iTrader: (4)

+1 on a lot of what has already been said. Flush all the fluids you can and fill with proper fluids. Motul makes amazing stuff, Gear300 for our transmissions, gear300ls (for the sport vlsd), RBF600 for brakes (and clutch for manual transmissions). ATE Typ200 is a step above OEM brake fluid and a step below RBF600, with a 3yr service interval compared to 2yrs for RBF600. Only use ester-based engine oils such as Motul, Redline, or OEM oil. There are more esters out there but most stick to those. Stick with OEM Nissan/Infiniti coolant (unless tracking, different story).

You mentioned you have 80k miles on it, so I would start with that along with replacing your spark plugs. If they hadn’t been changed that could 100% be the source of your rough idle you mentioned. Check your serpentine belt also for any signs of wear, if it hasn’t been replaced already- might be worth considering as well. I’d also go ahead and put in new drop-in air intake filters and a new cabin air filter, and clean the MAF sensors to be safe. I’m a dealer mechanic for Volvo, and you’d be amazed at how many cars and trade-ins we get that had work “performed” by another shop or dealer and the part was never replaced/changed/cleaned etc.

Also check all of the coolant lines, radiator hoses and clamps. The OEM radiator hoses and clamps are known to develop leaks overtime. As others said, if you have to replace them, you can go with a lifetime set of silicone hoses, but be warned silicone hoses permeate. OEM radiator hoses are recommended by Seb at SpecialtyZ (owner and master tuner). +1 also for a metal heater hose coupler from Z1, CZP, gktech etc. As mentioned, the plastic OEM coupler will break, and it’s not an “if” but a “when” sadly. It’s something I would buy and keep on hand, maybe even in my car, if I still had the OEM plastic connector installed.

The only way to real power bumps on these motors sadly are with forced induction (turbo or supercharger). That is unless one wanted to spend serious money to build a motor…400hp (crank) naturally aspirated can be done on this platform, but getting past 400whp takes some serious time and investment without going forced induction. You will see some smaller gains with breather bolt-ons, which some consider decent gains- to each their own. The most bolt-on power gains will come from high-flow catalytic converters…the OEM cats and OEM exhaust are very restrictive. Several members suggested intakes also, and since you mentioned prioritizing mods on handling and visuals, try a set of K&N (oiled) or AFE (dry) drop-in filters for the OEM air boxes. They’ll help with throttle response, add a hair more sound, will add few extra hp (don’t expect a 10-20hp gain though) and cost a substantial amount less than most front mount intakes.

You can pair them with a set of post-MAF tubes which are made by several brands such as Z1, Mishimoto, CZP, etc. which will clean up the engine bay and help visually, and will open the intakes a bit more since they remove several of the plastic (un-needed) resonators on the OEM intake tubes. Many members including myself have tried several aftermarket intakes over the years and go back to this OEM+ setup; it just seems to run better, and the design is about as efficient as it gets regarding heat management and protection from the elements.

Sway bars will do wonders on the OEM suspension, and fully adjustable coilovers are a definitely a step above that with regards to handling changes, but need a few supporting mods to maximize alignment and height adjustability. Lowering springs work, but at an eventual cost/toll on your shocks, and don’t provide the best ride or most even drop sometimes. Urethane engine, transmission, and differential mounts will make a big difference at your mileage coming from OEM mounts. Front strut tower braces/bars (FSTB) are also popular and cheap mods to help stiffen the front slightly. Go with a steel or carbon (even carbon wrapped is better) FSTB if you can find one, since they maintain their strength more when heated. Aluminum might look pretty but isn’t the best option due to its thermal properties- sadly most FSTBs are aluminum.

Knew I was forgetting something. An Ecutek tune (even an off-the-shelf tune) for this car will be the best investment. True gains, Bluetooth app, better throttle response, safeguards, and…rpm adjustable launch control!

hexotic

nice, thats rare. Maybe they dont care anymore haha, but most people are usually told no.

rotarymike

iTrader: (4)

+1 on change all fluids. I'm a redline fanboy, but don't let me stop you from buying motul or amsoil or whatever.

From what @BULL was saying, the AWD ECU implements kind of an electronic limited slip using differential braking rather than pure gear, so I would stick with that until you're having issues putting the power down. Swaybars make an AMAZING difference. For exhaust I'm partial to Fast Intentions for cost v performance but that's still a $2500 exhaust, headers-back.

IMHO, other than controlling body roll with swaybars, sticky tires/less sidewall makes a huge difference in how the car handles. See if you can find a square set of 19" fronts from a Coupe Sport (they're on the marketplace often enough) or even the 18" duckfeet OEM Sport Sedan wheels. Then start looking into the big-brake Sport Akebono setup.

Like 370Zs, these cars are not cheap to modify, and don't reward simple mods with huge increases. OTOH, they already have close to 1HP/Liter which was the Honda S2000 holy grail. You're not going to turn a G37 into a Hellcat - accept that, and focus on tested mods (here is a good place to find out what people's experience with different mods are) and you'll have a nice sleeper sedan that no one will expect is as fast (accel but also handling) as it is.

Rochester

iTrader: (9)

Couldn't have said it better myself.

brezzsent

I'd get the Sport rear sway bar really makes the handling on the awd more neutral as the awd tends to understeer a bit. The sway bar makes the car feel more planted with less body roll. projectfreetv.onl

waplus