6MT Problems

[Boomer]

There are 3 pages over at the other site about gear grinding in 3rd and 2nd gear, mostly 3rd gear. Does anyone know of any others? Several posters are saying the gears grind primarily when they are cold, but it takes a loooong time to warm up. I've been meddling and telling them to not force it into a gear, but some are even trying the old "double hitch" method and still grinding. One owner has 400 miles on his and he gets a grind sometimes "babying" it. Others have a grind regardless of their technique. Will there be a TSB on this, anyone?

[2003z]

mine grinds, even when I baby it too.

[Boomer]

Originally posted by 2003z
mine grinds, even when I baby it too.

Ouch, this does not bode well for 6MT longevity. I thought we were past this, Nissan doesn't have a fix yet?

[NSANY]

Between this and the chronic discussions about possible front suspensions design flaws, I have to admit I'm getting a tad nervous. My Z doesn't exhibit any of these problems, but then again I don't put as much mileage on as some. Plus, I keep her garaged so the gearbox never gets too cold (which IMHO is probably the reason for the grinding).
And the suspension thing has me envisioning my Z having a steady diet of $150 tires every few months...

If anyone hears official news, definitely post here. I'd like to keep my finger on the pulse of these two issues, as they seem to be the leading gripes from the early owners.

- Chris

[2003z]

NSANY, I too keep my car garaged. By cold, I mean freshly started, My garage never seems to get below 45 degrees. I don't drive mine much either, and it didn't really start until 4800 miles.

[mk350z]

After 2000 miles in very cold weather in New England, the only thing I notice is a notchy feeling, rather than a grind, on the upshift from 1st to 2nd. This seems to go away after the car really gets warmed up. The dealer says they have no knowledge of the problem, yeah right. It only happens on the upshift.

I picked up the car the day before Thanksgiving, so it hasn't seen any warm weather yet. I'll see how it reacts if spring ever gets here.

Marc
PPW Enthusiast

[BILL T]

Mine works fine even when very cold. The only time I've ground any gears is when my coordination is off when very spirited driving. I'm not sure grinding is normal - if you can make it grind all the time you might visit the dealer, it might just be a simple adjustment that'll save your transmission.

[Goober]

Haven't had a problem either. Sitting at 3500 miles as a daily driver.

I do notice that on some special times, the shifts are as smooth as silk (no, not because of me). The stick seems to move easily, gears mesh perfectly and such. Doesn't matter the temp, whether it is the first or last start of the day, or how long it has been running. Happens every 10th use or so.

[Boomer]

Originally posted by Goober
Haven't had a problem either. Sitting at 3500 miles as a daily driver.

I do notice that on some special times, the shifts are as smooth as silk (no, not because of me). The stick seems to move easily, gears mesh perfectly and such. Doesn't matter the temp, whether it is the first or last start of the day, or how long it has been running. Happens every 10th use or so.

Why the variation? I wonder about such things. I have no ideas as to why it does it.

[Goober]

I've wondered to but since normally it feels, well, normal. I don't mind. I just take the smooth times as my Z thanking me for taking care of her.

[josed]

After 2800 mile mine started to severely grind going into 3rd from second. It will not do it if I go from 4th to 3rd. I took it o nissan, and they ordered a new transmission. They have not told me yet what the problem is

[Tere]

I'm currently at 2,700 miles, VIN 9113. Never once had a gear grind, and I do exercise the old gearbox extensively with both up and downshifts, with frequent quick upshifts at high rpms. I've found the Z to be one of the best MTs I've driven (including 3 other short-shift close-ratios).

[TCL]

I have no problems with mine but I'm very interested in knowing whether the issues are a result of one or more of the following:


1) A subset of the cars have a bad trans from the factory
2) All the cars have transmissions that are fragile and it's only a matter of time before they all experience problems. In this instance the life span will probably be function of how the car is shifted.
3) A lot of drivers using shifting techniques that are bad for the trans.

I'm inclinded to think it's #1 - some of the cars had bad transmissions from the outset

[Tere]

Originally posted by TCL
I have no problems with mine but I'm very interested in knowing whether the issues are a result of one or more of the following:


1) A subset of the cars have a bad trans from the factory
2) All the cars have transmissions that are fragile and it's only a matter of time before they all experience problems. In this instance the life span will probably be function of how the car is shifted.
3) A lot of drivers using shifting techniques that are bad for the trans.

I'm inclinded to think it's #1 - some of the cars had bad transmissions from the outset It may be a combination too. I remember a discussion about the clevis being a weak link in the early models; rumor is that it was fixed in the later VINs, but I'm not sure the VIN# switch point.

The Z MT is also very light weight with small synchros, so it may not put up with severe abuse; driver technique may play a big role in the abuse. I think we all remember the epic photo sequence of the guy trying to get his MT Z out of the parking spot -- now that's abuse. :crybaby:

There are a lot of first-time MT drivers getting Zs, and I don't think the Z is a good car for the new shifter to learn on. And we've got the folks who slam the shifter into gear; to shift quickly, it is not necessary to slam it into gear. Even quick shifting is a two-step process -- out of gear, a nanosecond pause, and into the next gate. Most MT race cars don't have synchros so they have to double-clutch -- that emphasizes the two-step process.

The shifter also needs to float freely -- it ain't a hand rest! If someone hangs onto it with even light pressure, it can't float freely, and could result in transmission damage. And for crying out loud, you don't grab the shifter with a choke hold to shift! Put your palm on top of the shifter and pull/push with your wrist, not your biceps! In other words, you don't have to be the incredible hulk to shift gears! ;)

All of the above isn't babying the car; it's driving it with good and race-proven technique. Take a look at the view of The Run that shows the shift and pedal views -- check out the driver's technique. My critiques are that he's a bit hesitant on brake to throttle and back (could be a course familiarity issue), he tends to ride the clutch too much (that's why you have a big inactive pedal to the left of the clutch -- put your foot on it when not clutching), and he uses the shift choke hold on forward shifting (1/3/5) -- shifts with his arm not his wrist, but his 2/4/6 shift technique is pretty good. You will see the two-step shift process in action. Also watch how much floating the shifter does -- it will move a lot, and the driver needs to let it move freely.

So, yep, I'll bet your item #3 is a big cause for many of the problems we are seeing.

[Boomer]

Originally posted by TCL
I have no problems with mine but I'm very interested in knowing whether the issues are a result of one or more of the following:


1) A subset of the cars have a bad trans from the factory
2) All the cars have transmissions that are fragile and it's only a matter of time before they all experience problems. In this instance the life span will probably be function of how the car is shifted.
3) A lot of drivers using shifting techniques that are bad for the trans.

I'm inclinded to think it's #1 - some of the cars had bad transmissions from the outset

I'm inclined to think you are right about #1, because Nissan is still replacing, not repairing the transmissions.

As for #s 2 and 3, someone used the analogy that the Z's transmission shifted like a precision-made rifle bolt. If you have ever sampled or used a rifle with a bolt action, you know that you can't rush the mechanism until it is properly aligned to its path. It will reward you with very smooth operation when you make sure you are very deliberate in following its path exactly. If you don't, it will jam or its components may break.

I think there is a number 4. I have read about owners trying to shift w/o using the clutch, just to see if they can. Invariably, you will screw up and may damage your sychronizers. This not smart or cool. You just reduce the life of your transmission.

I have a number 5. Owners who don't depress the clutch all the way to the floor. One of the worst and most injurious things you can do to a transmission. When you can't engage the cluch properly, the synchros can't do their job and you will get a grind.

I suspect Nissan may change the transmission synchros for 2004. If they do, one way to extend a transmission's life is to put multiple synchros on 2nd and 3rd gears. Some manufacturers use double synchros on 2nd and triple synchros on 3rd gear because those gears get the most use in driving. Whatever Nissan decides to do, I 'm sure 6MT drivers will benefit.

Boomer--use it or lose it, I don't care.

[Tere]

Forgot to add for the mod folks...

The best shifter mod would be a nice big ball shift knob that fits comfortably in the palm of your hand to promote good technique. The worst shifter mod I've seen is surprisingly the Nismo knob (vertical cylinder) as far as functionality is concerned.

[Devil Z]

One more reason I don't need to have the first one off the boat.
VIN# 13262 just went over 2k mi. and no problems whatsoever. I feel for you guys though. :no: :ugh:

[NSANY]

Originally posted by Boomer
I think there is a number 4. I have read about owners trying to shift w/o using the clutch, just to see if they can. Invariably, you will screw up and may damage your sychronizers. This not smart or cool. You just reduce the life of your transmission.

I love these people. It simply amazes me to think that people can disregard the clutch and think that they're so in tune with the rotational speed of their lay shaft that they (in their infinite idiocy) don't need to use it.

Reminds me of a friend who power shifted his '57 Jeep and ended up with needle bearings all over the place. He got to enjoy that feeling exactly ONCE before he was rebuilding his trans in the student parking lot at Texas Tech.

[2003z]

Originally posted by Boomer
I'm inclined to think you are right about #1, because Nissan is still replacing, not repairing the transmissions.



Unfortunately, Dealerships aren't allowed to fix transmissions anymore. Its all pull and replace, regardless of the car or problem.

[Tere]

Originally posted by 2003z
Unfortunately, Dealerships aren't allowed to fix transmissions anymore. Its all pull and replace, regardless of the car or problem. That's true -- they may also be having the engineers taking a look at the failed components to evaluate any improvements that could be made, so they need to have the entire failed tranny! And I think they're replacing some abused ones in the process. ;)

[Boomer]

Originally posted by 2003z
Unfortunately, Dealerships aren't allowed to fix transmissions anymore. Its all pull and replace, regardless of the car or problem.

Its probably more economical, they can control Quality rebuilds and the dealer can't. Makes a lot of sense, when you think about it.

[NSANY]

Interesting thing I learned the other day along the same lines...
My newly-acquired SE-R needed the front rotors cut, so I took 'em off and brought them to my buddy at the service dept. He said NNA rules are that all rotors must be cut ON THE CAR using a nifty new $9000 machine.

Must have something to do with a few too many jarheads screwing up the reassembly of a locking hub on a Pathfinder or XTerra now and then.

Made me realize that it's all about making sure there's no comeback work. Keep it as simple as possible!

[ZPRESENCE]

replaced at 9,000, problems started around 5,000miles, third gear grind and very notchy, I now have 4,000 on the new tranny, no problem yet!VIN 6762

[TCL]

Does anyone have a VIN under 1500 with a lot of miles on it without a transmission problem? I only drive mine on weekends so I'm only up to 2500 miles so far. I better try to get 10K-15K miles on it before my warranities expire just in case my transmission is also a time bomb. My VIN is in the 1400's.

[2003z]

I'm VIN 915, with about 7500 miles now. Mine used to grind going into 3rd gear when the engine was cold, and only on cold mornings. Now that its warmer, no more grind.

[Boomer]

Originally posted by TCL
Does anyone have a VIN under 1500 with a lot of miles on it without a transmission problem? I only drive mine on weekends so I'm only up to 2500 miles so far. I better try to get 10K-15K miles on it before my warranities expire just in case my transmission is also a time bomb. My VIN is in the 1400's.

You have a basic bumper to bumper warranty for 3 yrs and 36,000 miles, and a powertrain warranty for 5 years and 60,000 miles. The transmission is Not a wear item like a clutch plate, unless I've forgotten. The long powertrain warranty was a major factor in my buying Nissans and Toyotas. What could possibly expire warranty-wise, that worries you? You have 5 years for something to go wrong, if its going to do it.

I am confused; I have no such worries. If my 5AT goes out, I expect it will be replaced, since there will be no question of abuse. A sports car is designed to be driven hard, not abused, but high performance is why we buy them. If they can't handle it, they are worthless to me.

Example: I use the manual mode extensively to hear the engine rev when it goes over 5-6000rpms. I am careful about downshifting because it doesn't like being shifted into 2nd gear over 20mph or downshifted at all into 1st. I know that, so I try not to do it, but sometimes it happens rather suddenly w/o my intending it. I've only done it a couple of times and I expect the AT to take it in stride and not be damaged by it.

If it can't take it, its a bad sports car transmission and should be redesigned or dropped from the option list. Good sports cars should be very durable, or they will be nothing but rolling art. Thats nice, but I would sell such as quickly as I could. The Z is not a fragile car. Some components may be at the moment, but they won't be fragile for long or people like you and me won't buy them. The Z's 6MT transmission should not be fragile for long, because Nissan will fix the cause as quickly as they can for economic reasons, as well as not wanting continued bad publicity. Don't borrow trouble, drive your sports car like its supposed to be driven. Hard and fast is how you should drive it. Sports cars driven by timid drivers really aren't much fun, IMO. Why bother to buy otherwise?

Boomer--my opinion, use it or lose it.

[Boomer]

Originally posted by Tere
Forgot to add for the mod folks...

The best shifter mod would be a nice big ball shift knob that fits comfortably in the palm of your hand to promote good technique. The worst shifter mod I've seen is surprisingly the Nismo knob (vertical cylinder) as far as functionality is concerned.

I agree, Tere. Remember the pretty wood shift knob on the 240s? Whenever I shifted, it always felt too small and it was slippery in hot weather, I couldn't get the leverage I needed for positive shifts. I modified the 240 quite a bit, but the first was a big, black leather ball shift knob. It transformed the shifting for the better, I was able to snap off really fast shifts with enough leverage to avoid grinding the gears in almost any situation.

The NISMO shifter looks too skinny to provide any leverage, and it will be very hot to the touch in the sun. Its very attractive, but not utilitarian at all. Put it on for shows and getogathers, maybe, but use a knob like Tere describes to drive your car. No other style of shift knob is better, IMO.

[Boomer]

Originally posted by 2003z
I'm VIN 915, with about 7500 miles now. Mine used to grind going into 3rd gear when the engine was cold, and only on cold mornings. Now that its warmer, no more grind.

Are you using the OE transmission lubricant? Someone posted that the Zs use a lube rated GL4, and if some owners who have changed to a synthetic or other aftermarket lubricant, it may be rated at GL5. This grade/rating is not recommended by Nissan and may be causing your grind when cold. I am not familiar with the rating, but the poster said changing back to a GL4 rated lube stopped his problem.

If you still have the OE lube, ignore this post.

[2003z]

Originally posted by Boomer


If you still have the OE lube, ignore this post.

ignored. Like you said, its got a 5 year warranty, so I will worry about it next winter if it rears its ugly head again.

[Silverstone]

Mine now grinds shifting into third gear (4860 miles), Took it to Nissan and they ordered new tranny. They called HQ's and they seem to be aware about this tranny problem.

Shitty tranny or not - I still love my Z!!!

[Boomer]

Originally posted by Silverstone
Mine now grinds shifting into third gear (4860 miles), Took it to Nissan and they ordered new tranny. They called HQ's and they seem to be aware about this tranny problem.

Shitty tranny or not - I still love my Z!!!

A number of sports cars have double and triple synchronizers on 2nd and 3rd gears. I don't know if it is true of the Z or not. If it isn't, then Nissan may need to add them because 2nd and 3rd are the gears used most in an MT. It was true of mine and a lot of other people's cars I've heard.

[jtree007]

Before my accident my Tranny had lost its 3 gear syncro

[Dr Bonz]

VIN #1596 here at 3500 miles and no grind at all. My car is garaged and was not driven over the winter.

I think it was Raceboy who was using the Redline tranny oil but he used the Light Weight Shockproof and not the MTL/MT-90 mix that is recommended by Redline.

I still have the OEM fluid in but plan on switching to the Redline mixture shortly.

[AuburnZ]

VIN #769 and no transmission issues. No grinding when shifting the gears.

[rouxeny]

I can't remember my VIN off the top of my head, but I think it's somewhere around 1500. I got the car in September of last year and drove it through the winter. Never garaged it and it sat in snow fairly frequently. So far, I've got about 10,000 miles of fairly conservative driving. Of course, the clutch always hits the floor before any shifting, and I'm not a slam-shifter either. I do rest my right hand on the stick far more than I should, but I did that with my previous car and never had any real problems. If anything, the worst thing I do is that I probably slip the clutch a little too much on 1st when starting.

Basically, no problems with the tranny so far. The notchiness is less than when new, as are the overall vibrations. I haven't had any grinding ever, nor really any odd tranny sounds at all. I do have a slight whistle when I step on the gas, I wonder if it's some air intake sound that I never noticed before. It does not sound like a metallic noise. There are an assortment of rattles through the cabin. Most noticeable by me is some click emenating from the passenger door. I haven't found that one yet. I also have the dreaded window klunk and a small rattle from the rear view mirror.

Hopefully the next 10,000 miles will also be trouble free.

[AuburnZ]

Our main rattle was the one in the visor which I just got fixed this past week with the dealership replacing the light in the vanity mirror. So far, haven't really heard any other rattles.

[Boomer]

Originally posted by rouxeny
I can't remember my VIN off the top of my head, but I think it's somewhere around 1500. I got the car in September of last year and drove it through the winter. Never garaged it and it sat in snow fairly frequently. So far, I've got about 10,000 miles of fairly conservative driving. Of course, the clutch always hits the floor before any shifting, and I'm not a slam-shifter either. I do rest my right hand on the stick far more than I should, but I did that with my previous car and never had any real problems. If anything, the worst thing I do is that I probably slip the clutch a little too much on 1st when starting.

Basically, no problems with the tranny so far. The notchiness is less than when new, as are the overall vibrations. I haven't had any grinding ever, nor really any odd tranny sounds at all. I do have a slight whistle when I step on the gas, I wonder if it's some air intake sound that I never noticed before. It does not sound like a metallic noise. There are an assortment of rattles through the cabin. Most noticeable by me is some click emenating from the passenger door. I haven't found that one yet. I also have the dreaded window klunk and a small rattle from the rear view mirror.

Hopefully the next 10,000 miles will also be trouble free.

Window klunk? What window klunk? How come yours came with a window klunk and mine didn't? I feel slighted.

[Dr Bonz]

Really? Yours didn't come with the Klunk? It is, as you know, a port installed option. Maybe they forgot to put yours on?

I use mine to hold up my cell phone antenna:

[Boomer]

Originally posted by Dr Bonz
Really? Yours didn't come with the Klunk? It is, as you know, a port installed option. Maybe they forgot to put yours on?

I use mine to hold up my cell phone antenna:

Looks like everybody should have at least one, damn that port bunch, they're fallin down on the job.

[Silverstone]

Tranny installed today...'bout time. Wow what a difference: previously when shifting it was always kind of "blocky" now it's smooth as "butta" (best way I can 'splainit). When using the clutch I was doing some serious calf exercises, now it's just right.
Seems like it's a totally different beast.

Had to do some serious VDC-off riding tonight. Is it possible to fall in love with the same car twice?

[6klaunch]

VIN 2530. 5100 miles. I havn't had any problems with the transmission. Last Saturday, I noticed that I crunched 3rd gear a couple of times. I thought I was being sloppy with the clutch so didn't think much of it. I'll keep an eye on it.

Thanks for the info.

[alpine]

I've ben crusing the boards the past couple days, and I'm seeing plenty of familiar faces and tags.

Hopefully you guys aren't getting sick of this.

Anyways to get to the point:

A few days ago I got the 3rd gear grind.

Called 3 local dealers, none of them no ANYTHING about ANY problems with ANY transmissions.

All of them would be happy to look at it, it's going to take at least a day or two and IF there is something wrong then we'll take it from there.

I have seen posts all over from people who have had their trans repaired/rebuilt/replaced.

I'd like to see if anyone could give up some additional information as to which dealers, and dates of these serviced transmission so I can use that as leverage.

thank you all and please adivse!

[emone4o]

I'm also cruising boards trying to learn as much as I can about this tranny problem….and others. I think I take the cake with VIN 00201 and I just turned over 10k miles.

I had a feathering problem last year that was taken care of under warranty...but I had to fight the dealer before they agreed to replace the tires. The quality of workmanship was horrible, they scratched the rims up and it looks like they removed the old weights with a dull screwdriver. Needless to say I was very hesitant to take it back to the dealer last month when I noticed my seat covers wearing through on the driver seat bolsters. I brought it to a different dealer this time, but I'm still fighting with them because my wear is on the bottom part of the driver seat, on the hump between the drivers’ legs, and the wear from the picture in the TSB is on the side bolster.

I haven’t noticed any serious grinding yet, but I have noticed a very notchy feeling going from first to second and second to third. It’s more of a clicking than a grinding…but it doesn’t feel normal and I’m afraid that it’s the beginning of a serious tranny problem. I bought the car in Sept of 02’ and it’s been garaged during the winter. I don’t drive it very hard and I definitely know how to use a manual transmission.

Does anyone have any documentation from the dealer they brought their car too showing that the tranny was replaced under warranty? You can blank out your name and all the personal info, but that would be great ammo if I could walk into the dealer and with documentation showing that the tranny was replaced and they didn’t charge you anything. If anyone has anything like this for the seat wear problem also, that would be great.

[PHFloyd]

I get the slightly notchy gear feeling going from 1st to 2nd when the car is cold.
It is not helped by delay time in neutral.

[The Brickyard Rat]

My Brick has 14000 miles with no tranny problem; shifts like a fine Swiss watch. And that includes teaching my son to use a manny tranny.

One of the car mags on a long term test (I don't recall which mag) ran into a tranny issue after several thousand miles & the dealer fixed it.

My guess is two sources for the tranny problems: (1) Bozos that don't know how, or don't want, to shift properly and (2) some bad trannys from the factory.

[Tere]

I tend to agree with Rat. My 300 is tougher to shift than my 350. Of course, I set the 350 up specifically for my shifting techniques, but it shifts like a dream. Very quick and silky smooth on all upshifts and downshifts in all gears (including downshifts to first above 20 mph). Wish I could get my 300 set up that well (it has ambiguous gates). My 350 has almost 13,000 miles on it (VIN 9113, 11/02 production) and I probably upshift and downshift more than most -- very "spirited" driving most of the time.

From what I've seen, I think the tranny problem is pretty isolated, and can't be ascribed to a particular production run -- possibly a factory quality control problem. And then there's the other issue; I think most of us remember the classic video of the guy burning up his clutch trying to get his brand new Z out of a parking spot.

I can't emphasize enough the old "out of gear, rev match, and into gear" shifting process. Rev matching on upshifts and downshifts makes for very smooth shifting. My nephew was riding with me a few weeks ago (doing WOT and redline shifts) and commented that my shifting was smoother than an auto tranny. Without rev matching, I can pretty much guarantee notchiness or worse -- gear crunching, particularly with high rpm quick shifts. ;)

[NSANY]

Mega dittos on the RPM matching. With how most people shift gears, I'd love to see how they would do with a nice old non-synchronized dump truck. :D

[Tere]

LOL... How'd you guess... In my early teens, my three "learn-how-to-drive" vehicles were: 1. a '47 Willy's Jeep -- three on the column and a really finicky clutch, 2. a lord knows what year antique White dump truck -- no synchros; double-clutch city, and 3. an equally old Ford tractor. It was a few years before I even learned to drive on a road -- I just made my own roads. :D

[briankoenig03]

"Of course, I set the 350 up specifically for my shifting techniques"

Are you referring to changing fluids and changing to the lightweight clutch? Or did you do something else to fit your shifting style?

[Tere]

Clutch and short shifter... The shifter takes some playing with to get it set just right -- pattern (very tight) and ease of movement. It's about 2.5" gear to gear, and just takes a flick of the wrist to shift gears. The gates are well-defined, so it's almost impossible to miss a shift either up or down. A well set up shifter will gain you a tenth or two on the dragstrip, and also helps for tack and autocross. ;)

[haleo]

i have 06 that from day 1 of purchase tranny grind from 1 to 2 gear any one know what to do?