Need some experts help, I just bought an 06 350z last year. Bought the car with 73k miles and since than it is sitting at 76500 as of right now. During that time the clutch went out on it so I had a shop put in a new clutch, pilot bearing, throw out bearing, and new tranny fluid.I told them to check the flywheel while they were in there and they said it looked good.

Since the new clutch the car has given me nothing but issues when shifting from first to second. These issues started happening after I had the new clutch put in, I have never driven my car hard. The only reason I noticed the clutch was going is because when I pushed the clutch in it would make a whining noise and than stop upon releasing the clutch. It is very hard to explain the issue I am having because the issue is very inconsistent, sometimes it grinds when shifting into second from first gear and other times it shifts completely fine.

When I say the issue is inconsistent I mean very inconsistent. Some days ill drive it for an hour and it'll be completely fine the entire drive and other times ill drive it for an hour and it'll grind from 1st to 2nd the whole time. I have noticed that the temperature outside and the operating temperature in the tranny does play a role in how it shifts, I have noticed that the hotter it is the more it grinds. When I first start it up it doesn't grind at all but as the car gets warmer it starts to grind from 1st to 2nd.

I did experiment with it some and I also noticed that if I short shift it around 1500 rpm it wont grind or if I rev it out to 4k it wont grind, it is always around the 2-2500 rpm range that it always grinds. The grind is not bad by any means, it still goes into gear without resistance it just clunks into gear with a slight grind. I literally have no idea, ive tried taking it back to the same shop and told them what its doing and they always say "it seems fine" which is completely false lol. What are your guys thoughts? low tranny fluid? Slave cylinder? I find it hard to believe it would be anything more significant than that with only 76k miles.

 

Welcome and my first thought would be to ask what type of brake fluid was used when your clutch was replaced? Since these problems began after the work was done and seem to get worse with rising temps and low revs, I'd hazard the type and viscocity of tranny fluid might be a factor. A cheap suggestion might be to buy three quarts of Redline MT-85 and simply replace whatever the shop used. It's not a hard task to accomplish and every Z car owner should know how to do it.

 

What brake fluid do you suggest to run and since the tranny fluid is a cheap suggestion what transmission fluid do you suggest I run to maintain the transmission as best as possible? Don’t care how much it cost. Im just going to swap out all fluids and a new master switch since some suggest doing it with the clutch.

 

For brake fluid, I'd suggest ATE Super Blue DOT 4. Moderately priced and widely available. High wet boiling point and fully compatible with the DOT 3 fluid left in your Z. As for tranny fluid, I already suggested Redline MT-85 to maintain it, I use it in both my street and race Zs. If you're talking about the rear differential, that's a different story.

 

ill give that a try thank you very much!

 

Forgot to mention that ATE Super Blue was outlawed due to its blue color by the DOT here in the states. The same product, without the blue coloring, is also marketed under the name ATE Gold 200 and has the same rating and cost.

 

I finally got everything installed. I bought everything from Z1 Motorsports, I got there package that has slave cylinder, steel braided brake line, and master cylinder. Also got my tranny fluid changed with redline MT-85 and got the ATE 200 brake fluid. I just need some help adjusting the clutch pedal properly to the master cylinder.

The issue I am having is when I look up how to adjust the clutch pedal most people suggest about 3-4 threads showing on the bracket from the master cylinder that pins into the clutch pedal. Mine has about 3.5 threads showing and there is a solid 3-5 inches of play in the clutch pedal before it stiffens and you can feel the slave cylinder pushing on the bracket on the transmission. When I have someone compresses and decompress the pedal while I bleed it underneath there is plenty of pressure on the pedal but it is only dribbling fluid out of the bleeder valve almost like the master cylinder is not compressing all the way. Should I keep screwing the master cylinder in on the clutch pedal until it feels right despite what everyone says about how many threads should be showing?

Maybe the pedal is not snapping back all the way because of the clutch spring?

One last thing how much play should be in the clutch pedal? about 1-2 cm from the bracket that stops the clutch pedal?

 

Hi,

You need about 1 inch of play at the top of the peddle.

But, you need to get it Bled Properly then do final adjustment on peddle.

Bleeding is a pain. really need 2 people if you don't have all the pro tools.....

I've done this by my self, pumping the peddle like 30-40 time then holding it with a 2x4 wedged between the the seat bracket and peddle.

you pump it 30-40 time, hold the peddle, then open the bleeder. nothing will come out at first. just keep doing it. then repeat.

make sure to keep the resivor full of fluid.

you will start to get some peddle feel, just keeping pumping 30-40 time, and bleed again. in till NO AIR, NO Bubbles come out of the Bleeder.

for adjustment at this point.

make sure you have about 1 inch play at the top, this insures Full Engagement.

Make sure you can push the peddle to the FLOOR without it deflecting the Master Cylinder support.

Don't Go by how Manny threads are showing, that's B.S. every clutch is different.

if the clutch peddle id deflecting like you said, then ROD is to LONG, back it off 1/2 turn at a time in till it feels good.

Start the car, keep the peddle to the floor, put the car in Gear, making sure there is No Drag on the clutch, car wanting to more.

Let me know if you have anymore problems.......

Also, I used this Amsoil..... I can tell you I've Tried ever different Trans Lube I could find to make mt 6 speed shift better. This is the only one that worked, and it make a Big Difference.

I Race my car at the drag strip, and shift need to be easy shifting at 8000rpm.

TimRod

 

Welp, I am not sure were to go from here. Clutch has less than 3k miles on it. I just put new Redline MT-85 filled correctly just dripping out of the fill hole. Transmission fluid has less than 100 miles on it, just installed brand new slave cylinder, brand new master cylinder, brand new steel bradded clutch line. All parts are from Z1 motorsports. Clutch has been bled extremely well not a single air bubble, peddle as been adjusted correctly. I still have a slight grind from 1st-2nd and from 2nd-3rd. The issue is still very inconsistent it typically does it in the 2-2500 RPM range. If I rev the car past 3k it shifts smooth as butter. By inconsistent sometimes it does this and sometimes it does. The car shifted completely fine when I first bought it, smooth as a hot knife cutting through warm butter. Only reason I knew the clutch went out was because when I held the clutch down it made a whining sound.

I bought the car at 73k miles, clutch went out about 74k. I had a shop put a new clutch in and I told them to check the flywheel, they said it looked good and slapped it back in, it was not resurfaced or replaced. The grinding issues happened after the shop put the new clutch in. I brought the car back like 3 times and told them it wasn't right but they insisted "it seems fine." At the time being my first manual I didnt know squat but as I own this car longer I am starting to figure things out. I had a guy mention to me that it could be a possible flywheel issue but he also mentioned synchro's. Let me know what you guys think. This is driving me nuts, cant stand paying insurance on this beautiful car just to let it sit in the garage. About to drop the tranny myself since apparently no one in my area knows jack squat about the 350z platform otherwise it would have been done correctly the first time the tranny was dropped. If you have suggestions for Synchro's and flywheels that would be greatly appreciated.

 

Sorry to hear that this grinding issue continues to plague you. As I said when I first suggested the MT85, it's a relatively cheap fix to try. But beyond attempting to make sure the clutch is properly bled and components installed correctly, the choices get harder. But here's a few questions for you to ponder:

1) You mention an inconsistent grind when upshifting, but what happens on downshifts? Usually, worn syncros get worse when downshifting from the 3-2 downshift and will be grind quite a bit going from 2-1.
2) You mention this problem seemingly gets worse as the tranny warms up. Does this consistently happen?
3) If you upshift consistently at 3K, does the grinding stop?

Strange that the problem started when you changed just the clutch and pressure plate. I wonder if you had the original dual mass flywheel or if it was replaced with a single mass aftermarket unit. And while this seems like an inconvenience, are you not driving the car b/c you think it's damaging it permanently?

 

Suggestion: When it happens again, hold the clutch peddle to the floor (hard and hold it there) immediately see if it happens repeatedly while shifting into and out of gear. If it does, suspect the transmission's internal synchronizers. If not, suspect that the clutch is not dis-engaging enough. Why? Perhaps incorrect or defective parts, misalignment or improper installation, and possibly the shifter not aligned correctly. Is the correct oil in the transmission ? Is it full ?

Good luck !

 

Thank you for your quick responses. I did experiment and test the car some today. I adjusted my pedal outward so the length of the master cyclinder rod is longer. This did help with the grinding but you can really feel the gears. Not sure how to describe it, like when the car is turned off and you put it into gear that's how it felt when I adjusted the pedal outward. It was just a test but it is at an unsettling distance. About a quarter inch of free play, If I lightly press my foot on the pedal while driving there is not much wiggle room before it starts to ride the clutch. Bite point is just very slightly past halfway, it was not riding the clutch but to close for comfort.

I did some down shifting from 3rd-2nd and from 2nd-1st with regular driving. I do not hotrod this car it is very nice, except for the tranny issues atm...... downshifting from 3rd-2nd it does not grind but like I said before you can really feel the gears, it is not smooth how it should be, like if the car is off and you put it into gear. downshifting from 2nd-1st it also does not grind but 1st goes in pretty difficult like it just hits a wall and doesn't want to go.

About 90% of the time when I upshift past 3k rpm it does not grind at all and shifts as smooth as butter as it should. Like once in a blue moon it has a slight grind past 3k.

The problem does get worse as the tranny warms up. typically when I start driving in the morning it shifts completely fine. Driving on Hot days or driving for more than 30 mins when everything is at operating temperature is when I get the most grinding.

I am still driving the car but it is very demotivating with the tranny issues at the moment. I don't think it will cause permanent damage, I just dont want to keep driving the car around if it is just going to cause more damage and cost me more money. Ive have already been burning a hole in my pocket with this car lol. paid 10k for it, put a new clutch in right after for 1500, routine maintenance cost, just spent 400 on the clutch pedal system and tranny fluid, just bought brake pads. I easily have a good 2-2500 wrapped up in parts already in just a year on a car with only 77k miles. Like honestly being my first manual and buying my dream car at 21 has really been a poor experience so far lol.

I know that transmission is in good shape, I know that shop did something wrong I just don't know what. When I first bought this car everything was great, as soon as I had the clutch put in it has never seemed right since. I brought the car back to the shop about 3 times and told them it wasnt right and they just said they didnt hear anything. Pretty typical around my area, the "professional" shops have about as much integrity as the guy on Facebook market claiming "just needs a battery, will fire right up"

If you think I should drop the tranny I have no problem doing that. It is my first manual but I am also a motorcycle mechanic at a Honda dealership so I have experience doing difficult jobs like so and making sure there right. This would be my first time dropping a transmission but I know how to follow the manual and torque everything to spec, patience is definitely key when doing things like this. Just not really sure what I should be looking for in the transmission that would cause these issues or what to replace.

I do agree with J-CAT though that it does seem like it may be misaligned or not installed correctly. I know they make a special tool for aligning these things and I'm sure the shop did not use it at all. Probably gave it the good ole eyeball it down and call it good. Another thing I wanted to bring up was, do you think the pilot bearing could be pushed in to far? I was doing some research but I do not recall what they said, I just know they said something about the pilot bearing being pushed in to far can cause issues in the transmission.

J-CAT - I just put some Redline MT-85 Tranny fluid in just slightly over 3 quarts until it was dripping out of the fill hole, not draining just dripping. Tranny fluid has less than 100 miles on it. I will try that tomorrow and see what it does. Thank you for your feedback!

 

Hi, we went over all these Issus over the phone.

If you have done everything we talked about, and I know you did, Then:

I'f you are not happy with how your car shifts, and you want to spend more money, Then:

Drap the Trans, and either get a Brand New CD009 or CD00A, or at the very lease a good used CD009 ( I see used ones for sale a lot, but you never know what your going to get. If you plan on keep this car, get a New one.

As I told you the History of this Transmission and the the problems it's had. CD009 or CD00A is the only way to go.

While the Trans is out, either have the Fly wheel Surfaced, or get a New Flywheel like a JWT, or some other good quality Aftermarket one.

Yes, you need an Alinement Tool to install the Clutch, they are like $10. It's is just for the purpose of gettting the Spline in the disc lined up some the trans input shaft will go in easy. If the Trans is in, then it's Alined.

This is just the Price of buying a Used Car.

It's has low miles, so fix it and you will have a great car.

Sincerely,
TimRod