weird 6th gear problem

corbin09

Hey all i dont know if anyone else has experienced this, but on a wot run, in 5th at pretty high rmps, i went to shift over to 6th, I wasnt at redline mind you but probably around 6k, and it wouldnt go into gear, so i let off the clutch and tried again and got the same problem. I didnt double clutch but i shouldnt have to right? has anyone else had problems with this in any gear including 6th and is this normal for these cars? (i came from an s4 and am new to nissan) Any help would be greatly appreciated.

m4a1mustang

The 6th gear synchros suck. I don't think this is an uncommon problem. I know it's difficult to engage 6th gear quickly in mine so I've been either shifting very slowly and/or double-clutching to make it a little easier.

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6SPD_FTW

ABSOLUTELY agree that 6th gear synchro sucks! It will die soon! Mine started being very difficult to get into 6th at around 4000mi. At 5000mi, I got the 1st CRUNCH going into 6th. It grinds everytime I shift into 6th gear now, unless I do it very, very gently.

Bad 6th gear synchro is a pretty common problem on the 370Z. No recalls from Nissan, yet.

And the best of all is that 5th has started doing it also. GO Nissan...LOL.

I haven't taken it to Nissan, yet. Just been living with it. But I'm gonna go really soon and see what my dealer says.

Late,
Trav

TX_370

+1

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corbin09

wow that is bs... i have had my car for 4 weeks... and i cant believe im already having trouble with it. My brother has a nice 350 and he said he has never had any problems with it? I am going to take it to the dealership this week but i think its crazy that things are already messing up on my BRAND NEW car. Do you think they will replace the tranny if the problem persists or will they try to beat around the bush and since it only happens when going into 6th hard will they say that it wont affect my daily driving?

m4a1mustang

I think a member here had his transmission replaced because it was so f'd up.

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Josh@STILLEN

I wouldn't wait.. and their fix is a new transmission.. I'm on transmission #4

corbin09

I am PISSED... i just got off the phone with nissan and i told him my problem. The first thing he asked was how fast were you going that high up in the rpms in 5th. I responded with that is irrelevant and when he asked again saying he couldnt help diagnose a problem without knowing i said 100 in a controlled environment. He stated that there is some kind of rev limiter on the car limiting from shifting into 6th going over 120. I am SURE this is a load of BULLS*it. The on top of that to make me even more mad they had the balls to ask me to pay for a rental car.... (NOT HAPPENING). my car also does the 1st gear chatter which pisses me off as well but i figured it was normal? Anyone else had this bad of an experience with nissan? Also i made SURE to make the service tech note that the car was wayyyyy too hot for the texas summer and he needed to find something to do asap to fix it... he said it is find for normal driving conditions and they havent had 1 problem....Im fixing to trade this piece back in.

wstar

It's about as easy for them to run the numbers as it was for me when I first read this thread (6K in 5th on a 6MT = ~128mph), if I were you I'd find some other way to explain the problem to them than claiming you expect that to work on the street, because they will drag out the "that's illegal everywhere and/or you're tracking the car so we can't help you" angle.

Anyways, running the numbers some more makes for an interesting angle on their claims about 6th either not being designed to be shifted into at high RPM and/or it being limited/locked-out from those shifts.

On the Sports Package wheels and rubber, on a 6MT car, 7500 RPM in 5th is right at 160mph, which is also the ECU speed limiter. So technically, that means there's no reason to go to 6th at high speed at all except as an overdrive gear to drop the revs and cruise with more efficiency. Even then at those speeds it's not much of an overdrive: at 160mph (7500RPM), the 5->6 shift drops you to about 6K. At 128mph, for comparison, the 5->6 shift drops you from 6K to about 4750.

So their angle here may be that they know the 6th synchros are weak for a hard high-rpm shift and they don't care, because honestly if you're accelerating hard at those speed ranges, there's no reason to leave 5th ever on the stock ECU. If you wanted to back off the throttle and then cruise somewhere in that range, then you'd go to 6th, but that would be a soft and simple shift, not a WOT shift into 6th still accelerating.

You might play with it more and see if this line of reasoning holds up. I don't have a 6MT so I can't really help.

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Scribe

That was me!

They replaced the trans, no questions asked. It'll get worse, and when it won't go into gear without scratching, take it in.

wstar

BTW, good link for playing with gear numbers, that I used above:

Gear-Speed Calculator Program

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ZKindaGuy

There is NO problem or defect...I had the same issue until I discovered that I was putting a very slight downward pressure on the shift knob when trying to go into 6th gear. This engages an anticipated prep for going into REVERSE. However because the car is moving forward the REVERSE shift lock gets engaged obviously for safety reasons. This prevents any upshift into 6th AND into REVERSE and causes you to have to either go into neutral and retry the 6th gear shift or to downshift into 5th and then re-shift into 6th WITHOUT any downward pressure on the shift knob.

This isn't any bullsh*t either as I have done this at least a dozen times an was able to reproduce it over and over again exactly as I described above. And it only takes the slightest amount or almost imperceptable down-pressure on the shift knob which is why it is not easy to detect at all.

DannyGT

Your correct, no bulls anywhere..

I actually reproduced this as well and I found going into 6th by almost cupping the shifter in an upward manner would result is perfect shifts everytime.

But its true what wstar said, I know I never need to shift into 6th at 150+ under wot...Just use 5th unless your really looking to dragrace/mile race someone on the street. But still who needs to be doing that so agressivly on the street ?

Road coarse > Drag

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xiven

I agree...just leave it in 5th. You'll have more power in that gear anyways.

corbin09

So yesterday I took my car to the dealership for the biggest waste of a lunch break ever. I mentioned the oil overheating problem and he said it was normal in texas weather to have it around 260-280(uhhhhh dont think so). Then my main concern the transmission. He said that there was NO reason i should be driving the car that fast which to me is irrelevant to why it is broken but he said that since he or any of his employees cannot drive it that fast to diagnose the problem there was not much he could do for me. I am furious, my particular car has only 3k miles on it.