Possible Nissan OEM clutch system issue - Everyone Read

RCZ

Well, the issue isnt in the parts. In fact there are a lot of happy people with the same clutch in the 370z. The problem is that the grabbiness of that clutch exacerbates the issue much more than the stock setup does. I no longer have the Southbend installed, replaced it with a ClutchMasters Stage 2 and all of my big problems are essentially gone. Why? Because the Clutchmasters is a much more forgiving clutch so it allows that drag to go by unnoticed, just like the stock clutch does. I would bet the farm on the fact that a whole lot of people have clutch drag and don't know it because the stock clutch hides it.

Compared to my '06 STI, my car's transmission is junk. There was nothing more satisfying than revmatching and going through the gears in that car (specially after kartboy bushings). In this one, I dread having to shift. I am not getting any grinding or clanking. The only problem I have is the one caused by the clutch drag; resistance to going into gears smoothly.

And whats with the crazy bogging when you hit the gas hard at low rpm. It is clearly being held back electronically. Whether its supposed to or not, it sucks for drivability. Sometimes I want to merge into traffic quickly and the car just makes noise and goes nowhere until a little bit higher in the revs. I'm not expecting full torque at 1000rpm, this is different. This has been reported many many times and there are a ton of threads about it AND the car did it before the SC..so I know its not that either.

Why Nissan!

DIGItonium

[OT]
Yea, the throttle control transition is not always smooth. I have my foot down and steady, and it feels like it is oscillating between throttle position values even though the clutch is fully engaged.

There are other times when I progressively press further down on the pedal I would expect an increase in response, but instead it's either a flat spot or a tease (it rises, but plateaus the rest of the pedal travel as if throttle hit a low ceiling).

I've done some tests where I get the car rolling in 2nd around 1k RPM and then flooring it. When it is "cool," the revs ramp up very quickly. After driving for awhile, it takes forever to ramp up past 4-5k RPM. Pre-VHR engines don't do this. Because of this, sometimes I have a hard time getting the turbos to spool up. In 2nd and 4k, there's no boost as if throttle wasn't opening fully.
[/OT]

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livethefunk

it seems like a lot of these mt problems have been happening before the 36k warranty which is good for everyone. Im scared because I bought mine used and its about to break 36k. I have no idea how the person before me drove the car but the mt seems strong with no problems yet. I just don't want something to happen later down the road with me not being able to afford it.

Davey

Well that sucks. I thought the stock STI trans was... OK. Mine had about everything Group N/Kartboy/Turn In Concepts you could get as far as driveline stiffening on it and I still didn't think it was that great. I didn't think it could hold a candle to my S2000, but that is no surprise, not many things can compare to that trans.

But it's not like my HR Z felt like a hunk of crap compared to the S2K (other than the clanking) and the 370Z feels better than the HRZ, so, like I said, I think your transmission has a problem.

I don't have that problem, either, thankfully.

I guess I'm just rubbing it in...

Nah, I just know these problems don't happen with every Nissan, and complaining about it on forums isn't going to do anything. Complaining to dealers and complaining to NIssan is what would solve the problem. Loss of power is a serious issue. If you can reproduce it regularly, take it for service. If they can't fix it, LEMON LAW THE DAMN THING. Nissan will take notice when it starts costing them money...

RCZ

Nope, Nissan will not do a damn thing for me, much less the ignorant, lazy jerkoffs that roam the service department at my dealership.

I hear that S2k tranny is amazing! I test drove it once, but I didnt think anything of it. I guess I didnt get enough time to really appreciate it.

You don't have that problem? Floor it at low rpm in second gear when the car is warm and tell us what happens. You will get this lag...nothing...then all of the sudden, like an on switch, car takes off.

Just like DIGI, when the car is cold, it drives the way it should drive all the time. Very responsive and smooth. Soon as it heats up, it changes completely.

Also, I dont think you're rubbing anything in. Its clearly happening to some people and not to others. Just consider yourself lucky its not happening to you!

Davey

That sucks Nissan won't do anything for you.

I really don't have the issue that I can tell. I floor the car all the time from ~2,000 RPM. Actually it's one of the things I like about the car - it doesn't have torque like a V8 or anything but it's not anemic like a 4-banger is, I felt like the V6 is a nice compromise in that regard.

I've never felt it lag at all, except when the traction control has come on (cold/wet/both) and most of the time when I goof around it's after I've driven the car for half an hour or more on the highway, and I tend to pass pretty aggressively, so, you know, oil temps are up to 220 or so. We had NO spring this year so it was up around 100 degrees almost every day this summer since I got it... The car spent a lot of time good and hot.

I do consider myself lucky, for sure. I heard about all the trans issues with the 350Z, too, and I knew about DIGItonium's issue from the other thread... Been really hoping I never experience it and so far I have not.

I mean, I'll put it this way. I like the car. It's not the greatest, but, I do like the car a lot. I wish the brakes got some cooling and it had an oil cooler. I hate to see someone else having a bad time with the car. If I had to put up with the **** you guys are dealing with, I'd be outright raging mad.

Perfourmance

yes, the s2k has, eeeer had (), an unbelievable gearbox. You had to be careful shifting quickly and aggressively from 1st to 2nd in the AP1 (9k rpm limiter)...it was slightly remedied in the 2.2 liter (AP2) with a reduction in limiter and different synchros.

so now i've gotten: 1) notchy gearbox with lurch, judder, and resistance to downshit 2) oil temp issues with "spirited driving" and now 3) "bogging" at low rpm with the car up to op temp

Evo X <--> 370Z !?

granted, the EVO has issues of its own...the MR TC-SST only handles ~300 tq and can't be worked on, yet, by Mitsu. The GSR (5 speed) apparently has a pin breakage issue within the trans...not to mention those guys (evolutionm) have a 51 page thread about the notchiness of the 5 speed; go figure!?

bottom line, picking apart every car's weakness isnt going to get me anywhere and basing a purchase decision on a couple bad apples is heinous. i just hate to hear that this experience has ruined the car for some of you guys.

Davey

Dude, even the almighty mustang has piston slap, grind, broken transmissions, etc. if you read the interwebs. Oh, that garbage Chinese getrag, you know.

What I'm saying is, you are right, you can't judge your experience based on what other people's problems have been.

If that were the case, I would have never bought the S2000, because the differential explodes the 1st time you floor it, and the tops all get rip in them from the inside, etc. And I would never have bought the 350Z because everyone had their transmission replaced 4 times under warranty, the power window motors fail every other week, etc.

I don't have any issues with my 370Z. I feel bad for the people who do, but I don't believe I'm the exception to this, I believe there are a number of people with transmission issues and (whatever is causing) the bogging but it's not something I would worry about when buying the car.

I hate that these guys can't get any movement from the dealer on the problems. "It's normal" = ********.

DIGItonium

The issues I have are just annoyances (some that can be fixed for adjustments), but this is my only car and it is a daily driver. Being that, I'm still driving it. Most of the time it is not notchy, but either the CSC is not throwing far enough or the clutch disc is dragging is when it's notchy. Of course, this is isolated to the South Bend and ZSpeed combo. At least it's not impossible to drive the car, and I can still enjoy it 95% of the time. In the 350Z, the notchiness was permanent regardless of how fast or slow I'm shifting. This is leagues better.

IMO, sports cars like ours should require oil coolers from the factory (like the 335i, and I think Mustang Boss 302?).

As for bogging at low revs, it's due in part to throttle response changing (i.e., it doesn't open up as much or fast enough at the same pedal position) after the car has been driven for awhile. It comes and goes, but it doesn't make the car impossible to drive. It just requires pressing the pedal down a bit more. All I'd like to see from Nissan is an ECU program that retains consistency and bring back the neck snapping response from the 350Z.

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esfourteen

I agree with digi, the only issues I have are annoyances. I can occasionally grind 1st -> 2nd if im really driving it hard but its not frequent enough to reproduce and have nissan warranty it. Not everyone experiences this grind, but I started getting it with 300 miles on the car.

The transmission is noisy and not the smoothest, but I still enjoy driving it and wouldn't trade for an automatic. Perhaps once you drive a more refined gearbox (M3) this transmission might feel worse =]

My issue with lurching and clutch dragging is related to the clutch I chose (southbend), I sent it back and hopefully they can tell me what was causing it as I'd like to use the clutch again if I go FI, it felt great aside from the frequent engagement issues.

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RCZ

^ I've driven completely stock cars that have the lurch problem. Its definitely not just Southbend Z speed combos.

As far as buying or not buying this car...like all other cars in this segment, they have limitations and things aren't always perfect. That, however, is NOT a reason to excuse it. Its not ok for things not to work correctly just because other companies have problems with it too. I for one would hope my 43k car can shift and accelerate smoothly. Of course Nissan won't lift a finger until I'm stranded on the side of a highway somewhere.

Davey

Well, I'm not saying it excuses it, I'm saying that there are going to be a certain range of cars that shift like crap, have a transmission explode, etc. in any collection of cars due to production tolerances.

stanley79finn

I've noticed it on several z's. Never on mine though.

ImportConvert

As I suspected, there is no problem with the car. When you have the transmission in neutral and the clutch is engaged, everything in the transmission is spinning EXCEPT the output shaft.

That means that all those gears are doing what, 700rpm (I don't know what a 370Z idles at)?

As many of you have noted, the transmission can handle some power. I have taken a look at pictures of the gears online, and they are not puny. They have some mass to 'em.

Then you put it in first and the output shaft is engaged.

Guess what? All the inertia of that transmissions internals spinning at 700rpm hits the rear end as the output shaft comes into play.

Of course it's going to roll forward a foot or two if you whip it from neutral to first. To test this, why don't you crank the car and KEEP the clutch fully depressed. Then shift to neutral, NEVER RELEASING THE CLUTCH, keep it there 60 seconds, and shift into 1st. I bet dollars to doughnuts 0 lurch. Now put it back in neutral, let the clutch out, and after 3 or 4 seconds stab the clutch and jam second. Roll.

*This is as far as I have read in this thread, so if someone already said all this jazz, sorry to re-hash.

B&W_Evader

The tranny in every car I've owned has had it's own personality.

72 Ford Capri 2.0L - Worked great, fast shifting flawless 4 spd
72 Porshe 914 - Super finiky, needed light touch whenever it wasn't redlined, flawless when shifted at redline. To go into first, need to be at dead stop and put it into sencond gear first. Then a whip over to the left and down on the shift knob.
71 240Z - Flawless tranny - Abused the hell out of it for over 100k, driveline started loosening up from all the U-Joint replacements
69 Corvette - Super-T10 tranny - Semi-finiky, needed to be shifted slow or it would grind.
96 Tacoma - Need to be gentle, about the same as the Vette
2011 370Z - Little bit mor finiky than the Vette. Ultra slow shift and does not like to be put into first between 0-10 mph while on the breaks. (it clunks)

Your tranny is like a woman, figure out how she likes it and then give it to her.

I've only broke 1 tranny, the main gear came out the side of the casing... DOH! (friend's 68 camero with indy tranny) What a POS!