I don't know if any of you have this problem. I have a 04 6 MT and when I am at high rpm, I have a difficulty getting into 3rd.
For example, at 60 mph when I am in 5th and want to accelerate really fast,it doesn't want to go straight to 3rd.Also, when I am in 4th at 65-70mph,it goes to 5th when I shift fast.It is really annoying. I told the dealer and they said everything is fine with my car.
I feel very insecure,sometimes I need to get out of a tough spot on the freeway and can not rely on 3rd at all. Kills the fun of driving my beloved G.
I would appreciate any advice.Thanks.

 

Most likely a safety feature, preventing fastest guys on the road like you, against blowing the engine. It is most likely same safety feature as the one that prevents you shifting into 2nd at considerable speeds, and shifting into 1st at any speed. It can be easily done if you can rev match, but at 60mph trying to shift into 3rd will probably put you around 5000-6000 rpms which is up there. I bet if you slow down to 50mph it will be no problem, so you just have to monitor the speed and figure out when the shift gates are open and when they are "blocked". Good luck and be safe.

 

Nope,l not a safety feature!
I can shift into any gear at anytime in any range with no complaints, grinds or sounds of any kind, so I know his problem is definately not normal.

Try another dealer and\or contact Infiniti consumer affairs.

 

Well you have to rev match.. the synchros can only do so much. I can put any gear in at any rev including near redline... if i rev it first of course. If I don't rev match, then sure, the synchros don't want that gear being selected. But that's totally normal.

Try this... cruise up to 70mph... put it in 6th. That should be about maybe 2300-2600rpm (dont recall exactly). Now.. clutch in, pull it out 6th, rev the engine to about 5000-5500rpm and move the stick from 6th to 3rd, then clutch out.... sync up your gas pedal moves with the clutching and it should take the gear nice and smooth and be ready to kick *** in 3rd right in the power band.

I do this in the types of situations you mention "need to get out a bad spot" which usually means a rock thrower is directly in front of me and i have to haul *** for a moment to get out from behind him and into the other lane.

you can try the above at lower speeds... cruise up to 40mph, put it in 4th... rev up to about 4000-5000rpm and put 2nd gear in...

 

Sorry to threadjack, but can someone explain to me the whole theory of rev matching? Before someone assume's I'm just a dumbass, please read the following carefully.

I revmatch all the time. It makes for much smoother disengagements when downshifting, and saves a bit of abuse on the clutch. I understand that specific purpose.

However, it seems many people suggest rev matching to help the synchros out when going from one gear to another. This is the part that I don't understand. When the clutch is fully engaged, the transmission should be free of the engine, correct? So what does it matter at what speed the engine is revving? The only thing revolving that should affect the transmission will be the driveshaft, which will be rotating at wheel speed divided by final drive ratio. So what am I missing?

 

Thank you guys for your quick response.mal TX, I did do the rev matching and it feels much better. That was a great advice. Now I have to get used to doing it faster.I am kind of used to just putting on gear quicker and revving the engine confuses me.Practice makes perfect.

 

Rev match my ****!
You dont have time for that bull**** unless your skipping gears (up or down)...
This is how I do it; I just down the clutch and shift quickly and it goes in, no problem, at any RPM in any gear. No thinking, no complicated formula, no rev match.

 

htownboy --

that's not good for your drivetrain, your performance, or your smooth ride.

but okay whatever

 

lokoto... yeah practice it and it won't be long. I can do it very very quickly and I don't waste "time" with the engine at the wrong revs. When you can do it fast enough, it almost seems as if you are not doing it.. you gas as you put the clutch in, your revs are already where they need to be from that, and it all happens so fast that you just take off.

i suggest practicing it at lower speeds like 40mph 4th to 2nd. 4th to 3rd at 40mph is also very easy since it is only about 1400 rpm difference... I was able to do that one pretty much instantly perfectly pretty quickly then I practiced the others.

anyone who claims they aren't doing this... they are revving up between the shifts and maybe even going too high and slipping the clutch.. which is not ideal (you want to minimize time to power transfer) but also works and is tolerated OK by the drivetrain.

 

I always rev match as I simply don't like the jerking when I don't. I also want to minimize the wear and damage on my tranny as well. Rev matching & heel and toe are pretty fun as well

 

As to rev matching when going "from gear to another" .... that should not be necessary if you are shifting "in rhythm" with the car. If you take too long to go from say, 3rd to 4th and now the revs are too low to enter 4th at the speed you are traveling.. you can either declutch anyway and get a jerk or you can rev a little and then declutch and have it be smooth. Your choice.. smooth = easier on the mechanical components but I think it's really more about ride comfort in this case cuz the tranny is strong.

One exception -- if you are trying to enter 1st gear... at say... 15-20mph, it will not go in no matter how much you synchro rev match.. for that you need to double clutch rev-match. So... say you are traveling 20mph in 2nd gear. You put the clutch in, select Neutral, then let the clutch out. Rev to about 3500rpm (or higher i forget just check it while driving in 1st at 20mph), push the clutch in quickly, then push the gear shift towards first.. it'll go in if the revs are close enough. Then you can declutch and you're in 1st. Contrary to popular belief there is no "lock-out" in 1st.. or any gear.. just limits to what the synchros can do and consequently the need to have the input/output shaft speeds fairly close (within tolerance of the synchros). For 1st gear that tolerance seems to be very very low.

 

u are absolutely correct. rev-matching has absolutely no bearing on the synchros doing their job. i really don't know why the so-called 'expert' stick shift drivers on these forums keep bringing up rev-matching when it comes to the actual shift of the gears.

 

OK... basics... we have an input shaft, a chosen gear (maybe N), and an output shaft.

The output shaft is ALWAYS attached to the rear tires by way of the differential. It always turns some multiple of the tire's speed.

The input shaft is attached to the engine's flywheel by way of the clutch. If the clutch pedal is pressed, it is either stopped or slowing down. If the pedal is up, it must spin at the same speed as the engine.

In between is the gears... one object.. the gear, cannot spin at two different speeds at the same time. So... if the input and output shafts are not spinning at the same speed... the gear cannot be selected.

Enter the synchros... you start to put the gear in.. the synchros bring the input shaft into sync w/ the output shaft so the gear can be selected.. then either your gas foot or the clutch brings the engine flywheel to the same speed as the input shaft.

ok i have to go but apply that to shifting up/or down and what happens during shifts (you clutch in, rpms drop, you move the gear, you clutch out, etc), apply the fact that synchros ability is not infinite, and it should all make sense (rev matching, double clutching, etc).

 

So to rev-match, can you rev it while in gear? Like...

Lets say you want to do a rev-match downshift into 3rd from 4th...would you...

1.Clutch in
2.Rev
3.Shift into 3rd
4.Clutch out


or....


1.Clutch in
2.Put in neutral (with clutch still in)
3.Rev
4.Shift into 3rd
5.Clutch out

Which one? Plan A or Plan B lol

 

Both plans are fine. In plan b though, you want to let the clutch out after putting into N.

In plan a, as you perform step 3 the synchros are bringing the input shaft up to speed to meet the output shaft so the gear can go in.. you will feel the shifter resist going into the gate momentarily, and then go in.

In plan b, if you were good enough at your rev matching, step 4 would practically suck the gearshift into the 3rd gear gate (i've been lucky enough to have that happen while playing with this) and your synchros will have done very little in the process.

plan b is called double clutching and is necessary to get into 1st gear at speed.