Yes, I understand that as cars get older they seem to lose that extra jump in their step. But I have a question.

My car just hit the 60k mark and even before this, I feel like it just doesn't have that oomph anymore. I replaced the air filter and have been using Mobil 1 synthetic oil in all of my oil changes which are pretty much every 3k miles.

Now when I took my car into the dealer multiple times for a window issue, I received 2 different loaners, both G35 sedans (last year before G37). One had 30k & the other 50k, but both had that extra push when I gassed it, like when I firstgot my car. Now I know that dealers have the advantage of keeping their loaners serviced on a more regular basis, but loaners also get beat up by thoses who are loaning them.

My car is a 2005 coupe and I don't ever really push it, in fact I find myself doing the opposite because gas prices have been pretty bad since I bought it. Also, I live in southern California.

With the 60k maintenance due, does anyone have any suggestions as to why this lack of performance seems to occur other than just aging? Any specific maintenance I should tend to first? And does anyone notice this lack of performance?

 

any performance mods? what have you done to the car since you got it? hows the gas mileage compared to when you first got it? you might just be used to it by now. go drive a geo metro for a week and your car will have its ***** back

 

No mods other than a Z-tube when I first bought the car. I've only done all the oil changes and replaced the air filter & rear brake pads & resurface rotors so far. The car still runs great with no problems, it just doesn't seem to have ***** anymore. I thought it was because I was used to it, but the loaners I drove are heavier and have the same HP as my car so why do they feel like they have that extra quickness. I guess what I'm asking is what does the dealer do to keep their loaners driving like new cars? And if that was the case, after driving the loaners for a week, it should have felt like a new car when I got my car back, but it didn't.

 

i cant say what the dealer does to maintain their loaners, i assume just a little more rigorous maintenance than the average joe. the fact that your loaners were newer Gs (sedan or not) wouln't have helped you feel like your coupe was brand new again when you got back in it. if they had been something more typical i would say you'd have gotten that new feeling back.

what was your window problem? what did the dealer do to fix it? why did you have to go back twice? did you feel it was performing worse before or after the dealer?

did you feel it was performing worse before or after the air filter (what did you put in btw)?

you might try a simple ECU reset just for good measure.

 

the loaners you drove have a different engine (HR vs DE) and more importantly have different rear end gear ratio (3.692 vs 3.36 if you are AT, 3.54 if you are MT)

When I first drove the 07 sedan I knew right away there was something other than engine that was making it peppier/snappier... I suspected shorter rear end gears... I researched and found out they are 3.692 (which also is on a few other Nissan vehicles) - that ended up being the very next mod I did and worth every penny.

 

OP if your talking about the 07-08 g35 sedan, Its a different engine that's why it is faster.

 

the FD is as much (if not more) of a difference... I dyno'd about the same as stock HR (more now)... and the 07 was still peppier - the 3.7 FD makes a big difference.

 

IMO, much of the reason why the final drive was increased to a 3.69 is because of the taller tires (.6" taller) and needing to motivate an additional 160lb to 220lb more heft with the same amount of torque when compared to the first gen car.

 

The loaners G's were the newer G37-styled G-sedans, but they were G35's. You know when they still had the 3.5. But they might be right about the HR.

The window problem was that over time, there was a gap developing between where the glass & molding sits. I took it to them and they ordered a new molding trim and supposedly fixed it. Then my window wouldn't go up or down a day after I got it back. So I took it back and they replaced the motor. Then the window was making noises when going up or down like something was touching the glass. So I took it back again and they said they replaced the motor again and re-aligned the glass. The window has been fine since, but it was a huge headache. Good thing I got it done right before my warranty expired.

I replaced the air filter with an OEM one. Gas mileage is approx. 10% better and it seems marginally better performace-wise.

 

What mod did you actually do? Cost & difficulty?

 

had the shorter ring & pinion gears installed... gear set was about $450 I think + $10 or so for crush sleeve... install was about $450 (iirc) had it installed with Quaife ATB differential (about $1500 or so)... this was 2-3 yrs ago so the numbers are off top of my head from what I remember.

there's a lot of info on the forum... just search FD or final drive.

 

Sorry if I don't have the proper understanding, but for the best-bang-for-your-dollar, would this be the best option? Couldn't you go with a supercharger or turbocharger for approx. the same amount of money & yield more performance?

 

you won’t get close to that price for FI (super charger or turbo)... but then again, the mods we are talking about are ttly different than FI (apples to oranges really).

The gears alone were good bang for the buck... the Quaife wasn’t (it’s good, but not worth the price).

It’s expensive to modify this car - not to many "Bang for the buck" mods.

 

It’s expensive to modify this car - not to many "Bang for the buck" mods

How true that is!

 

Okay, good info. But going back to the original idea of maintenance instead of modification. I'm still convinced there is a loss in performance that is or isn't associated with aging. What maintenance has anyone done that "refreshed" their car again? I'm not necessarily talking about a major difference, just noticable whether that is small or not.

Along with that, what 60k maintenance did everyone feel was worth doing?