6spd Manual Transmission
From Nissan 350Z & 370Z Wiki
ALSO SEE
GENERAL
What is it?
The 6-speed manual transmission has close-ratio gearing for short, effortless shifts that allow the driver full control of the engine power and torque on straightaways or windy roads, whatever your flavor.
6MT
"6MT" is a shorthand way of writing "6 speed manual transmission"
What are the gear ratios?
1: 3.794:1
2: 2.324:1
3: 1.624:1
4: 1.271:1
5: 1.000:0
6: 0.794:1
How much power will the transmission hold?
Currently there are owners running the stock 350Z transmission with power levels up to 650 wheel horsepower. However, power levels above 400whp will require an upgraded clutch. This evidence suggests the transmission is built to hold significantly more power than the 350Z comes in stock form.
What version do I have?
Do I need a transmission cooler?
MAINTENANCE AND TROUBLESHOOTING
How do you change the oil?
What kind of oil do I need?
What is the deal with GL4/5 oil?
I thought i might add to this, after much reading.
GL4 (additive package 4) contains anti rust agents. GL5 (additive package 5) contains demulsification agents.
The demulsification agents in GL5 spec oil are known to cause premature corrosion of yellow metals ie:- brass, which i believe are used in the 350z Transmission.
Hope this helps. :-)
How can I adjust the clutch?
I hear a clicking/rattling noise when I push the clutch in.=
I see a lot of 350Z transmissions have been replaced
During the 2003 introductory year, many 350Z owners reported problems with the 6 speed manual transmission. The symptoms reported included: gear grinding, trouble shifting, hard shifts, getting locked out of gears, among other problems. This is something any potential buyer should be aware of when looking into a 2003 (and some 2004) 350Z model.
Why did the G35 not experience the same problems?
This is not an easily defined answer, but it is most likely due to the driving nature of the 350Z owners versus the G35 owners. The symptoms are much more evident under hard driving conditions such as fast shifting, or shifting at high engine RPM. With few G35 owners pursuing "spirited" driving, there is most likely a lower reporting rate of problem transmissions. The G35 and 350Z use the same transmissions, so the failure rate given all other variables the same should be even.
What are the failure signs?
Signs that your 350Z transmission is problematic: gear grinding and difficult shifting are the most obvious symptoms.
How can I fix the grinding problem?
Hopefully you find this problem before the 350Z drivetrain warranty expires. The typical fix is to replace the transmission with a newer revision. If you do not get it replaced under warranty, expect to pay $1600 or more for a new one (plus labor expenses).
It feels hard to shift sometimes
Transmission replacement cost
If you do not get it replaced under warranty, expect to pay $1600 or more for a new one (plus labor expenses).
Drivetrain Definitions
Axle
- An axle is a central shaft for a rotating wheel or gear. In some cases the axle may be fixed in position with a bearing or bushing sitting inside the hole in the wheel or gear to allow the wheel or gear to rotate around the axle. In other cases the wheel or gear may be fixed to the axle, with bearings or bushings provided at the mounting points where the axle is supported.
Clutch
- A clutch is a subcomponent of an engine's transmission designed to allow engagement or disengagement of the engine to the gearbox or whatever apparatus is being driven.
- The coupling mechanism used on a mechanical power press to couple the flywheel to the crankshaft, either directly or through a gear train.
Differential
- A set of mechanical gears that eqaulises the power between the left and right drive wheels, particularly when cornering, when the outside wheel travels further than the inside wheel.
- A device - usually made of gears - that divides the torque between the driving wheels and permits the wheels to turn at different speeds. This is especially important when negotiating a corner, as the inside wheels turn more slowly than the outside wheels.
- A unit that takes the power of the rotating driveshaft at right angles to the rear axle and passes it to the axle. It will not only drive both rear axles at the same time, but will also allow them to turn at different speeds when negotiating turns. In this way the tires do not scuff or skid.
Driveshaft
- A driveshaft or driving shaft is a mechanical device for transferring power from the engine or motor to the point where useful work is applied. The 350Z incorporates a one-piece driveshaft which is actually carbon fiber reinforced plastic.
Final Drive
Flywheel
- A relatively large and heavy metal wheel that is attached to the back of the crankshaft to smooth out the firing impulses. It provides inertia to keep the crankshaft turning smoothly during the periods when no power is being applied. It also forms a base for the starter ring gear and, in manual transmission, for the clutch assembly. Also see engine flywheel and fluid flywheel.
- This is a large gear mounted to the back of the crankshaft which turns the engine when the starter is cranking.
- A flywheel is a heavy rotating disk used as a repository for angular momentum. Flywheels resist changes in their rotation speed, which helps steady the rotation of the shaft when an uneven torque is exerted on it by its power source such as a piston-based, (reciprocating) engine, or when the load placed on it is intermittent (such as a piston-based pump).
Gearbox
- A casing for gear sets that transmit power from one rotating shaft to another. A gear box has a number of functions: it is precisely bored to control gear and shaft alignment, it contains the gear oil, and it protects the gears and lubricant from water, dust, and other environmental contaminants. Gear boxes are used in a wide range of industrial, automotive, and home machinery.
- The shell (metal casing) in which a train of gears is sealed.
Gear Ratio
- The number of revolutions a driving (pinion) gear requires to turn a driven (ring) gear through one complete revolution. For a pair of gears, the ratio is found by dividing the number of teeth on the driven gear by the number of teeth on the driving pinion gear.
- A gearbox contains several toothed wheels that are connected and disconnected to each other in order to switch into the intended gear. The gear ratio is the ratio between the number of teeth of the two wheels that are connected at a given time. If one wheel has 25 teeth and the attached one has 50, there is a 2:1 ratio.
Limited Slip Differential
- A Limited Slip Differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In a car or automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
Pumpkin
- The rear pumpkin, or carrier, houses the final drive gears and differential.
Short Shifter
Toe
- Toe relates to the difference in the distance between the front of the tires and the rear of the tires on the same axle, or to the vehicle centerline. Toe-in, or positive toe, is defined as the front of the tires being closer together than the rear of the tires. Toe-out, or negative toe, is when the rear of the tires are closer together than the front of the tires. Zero toe is when the tires are parallel to each other.
- Effects of Toe: Excessive toe increases tire scuffing and results in tire wear and drag on the vehicle. Excessive toe-in, or positive toe, increases scuffing on the outside of the tire. Excessive toe-out, or negative toe, increases scuffing on the inside of the tire, and in some cases can cause a darting or wandering problem. Bias or bias-belted tires will commonly show a featheredge or saw-tooth toe wear pattern across the entire tire tread area. Any tire wear pattern caused by a toe condition can be further affected by an excess camber condition and may result in irregular wear patterns.