Gear Ratios

[Rice Killer]

I'm kinda at a loss here. I know in the CTS-V the auto is actually faster than the manual. But I seen that the ZL1 is going to have different gear ratios than the CTS-V so maybe GM improved on this a bit for the ZL1.

CTS-V Gear Ratios
1st: 3.01
2nd: 2.07
3rd: 1.43
4th: 1.00
5th: 0.84
6th: 0.57

ZL1 Gear Ratios
1st: 2.66
2nd: 1.78
3rd: 1.30
4th: 1.00
5th: .80
6th: .63

I do not know anything about gear ratios and was hoping somebody with some more knowledge would chime in and give their opinion on the ZL1s gear ratios. I know we don't have the gear ratios, not that I've seen, for the auto, but assuming that it's the same as the CTS-V, would the ZL1 manual gear ratios help it be more on par with the auto??

I keep going back and forth between the auto and the manual. I love the idea of having launch control but I think the auto might be faster. Any thoughts??

BTW, I'm not trying to start an Auto vs Manual debate. I know this has been covered..

[1BADZL1]

2010 Hydra-Matic 6L90 (MYD)
Hydra-Matic 6L90 six-speed RWD/AWD Car and Truck automatic transmission
2010 Model Year Summary

Carryover features and benefits from 2009 model year

2010 applications: New: GMT 610 Full Size Vans. Carryover : Chevrolet Silverado 2500 HD, GMC Sierra 2500 HD, Chevrolet Suburban 2500 HD, GMC Yukon XL 2500HD, Cadillac CTSv
- Increased Torque & Power Capacity for High Performance passenger car.

Increased torque capacity
The Hydra-Matic 6L90 allows higher-torque output engines to be used in truck applications that do not require a heavy-duty, commercial-style transmission, and in high performance passenger cars.

Overview
The Hydra-Matic 6L90 is six-speed automatic transmission for rear- and four-wheel-drive trucks, designed with modular flexibility and compatibility with advanced electronic controls. It is a heavy-duty version of the 6L80 six-speed automatic, with a strengthened input gearset which has two additional pinion gears for six total, and a strengthened output gearset, that uses wider gears than the 6L80. The 6L90 flexibilty extends to the clutches where the 6L90 has one more clutch plate than the 6L80 in each clutch for heavy duty applications. There is also a 6L90 "Lite" version without the additional clutch plate to more closely match application requirement where appropriate. The 6L90 shares about 75 percent of the parts as the 6L80, although the case of the 6L90 is 35mm longer than the 6L80 case.

The 6L90 has the capability for adaptive shift controls and other features such as grade braking, and Driver Shift Control with tap up/tap down shifting. A wide overall ratio spread of 6.04:1 allows a "steep" first gear, as well as very "tall" overdrive top gear for low-rpm highway cruising. With this wide ratio spread, acceleration is maximized, as is fuel economy. Engine noise is also lower during cruising. Both fifth and sixth gears are "overdrive" gears, for example.

As in the 6L80, gear changes from second to sixth gears are accomplished with clutch-to-clutch control, where an oncoming clutch is engaged and an "offgoing" clutch is released in a precise manner to achieve the ratio change. The first-to-second upshift, however, is a freewheeling action, where the second gear clutch engages while the first gear one-way clutch spins freely. This allows a greater degree of smoothness at lower vehicle speeds. The clutch-to-clutch shifting and single freewheeler allows significant reductions in packaging requirements.

Advances in transmission control modules allow the modules to exist reliably inside the transmission, where temperatures remain fairly constant compared to a body-mounted module. The transmission and module are assembled together, so no additional steps are necessary during vehicle assembly.

The 32-bit transmission control module (TCM) monitors transmission performance and compensates for normal wear in components such as clutch plates, so transmission performance remains consistent for the life of the transmission. The control module also "tests" the components of the transmission following assembly to optimize the interaction of the components. The module is compatible with future global applications.

DEXRON VI premium fluid validated to improve durability and shift stability and
was developed to have a more consistent viscosity profile; a more consistent shift performance in extreme conditions; and less degradation over time. Internal GM tests have demonstrated DEXRON VI delivers more than twice the durability and stability in friction tests compared to existing fluids. The DEXRON VI fluid was designed specifically and validated for the new family of GM six-speed automatic transmissions.

The 6L90 variant of the new Hydra-Matic six-speed automatics centers on the desire for common components and manufacturing tooling. The 6L90 six-speed contains three gearsets, a conventional input planetary gearset with six pinion gears, as well as one compound output gearset and one simple output gearset. The compound output gearset uses three sets of pinion gear pairs, with one set of pinions meshing with the sun gear and the other set with the ring gear. This arrangement allows for optimal ratio steps with a 6.04 overall ratio spread.

The torque converter is 300mm in diameter, and is available with a single-plate or dual plate
(for extreme high torque applications) lockup clutch, which makes use of GM's proprietary electronic controlled capacity clutch (ECCC) technology, which uses a small, regulated amount of slip to dampen out engine pulses. This creates a smoother running drivetrain, especially during shift events.

Low maintenance
For severe use, DEXRON VI fluid changes are the only maintenance recommended. For normal use there is no fluid change scheduled.

The Hydra-Matic 6L90 is produced in Ypsilanti, Michigan and Toledo, Ohio

[1BADZL1]

Gear ratios:
First: 4.03
Second: 2.36
Third: 1.53
Fourth: 1.15
Fifth: 0.85
Sixth: 0.67
Reverse: -3.06

[1BADZL1]

Originally Posted by Rice Killer

ZL1 Gear Ratios
1st: 2.66
2nd: 1.78
3rd: 1.30
4th: 1.00
5th: .80
6th: .63

I would like to clarify the ratios you posted.
These you posted above are for the MG9 and not the MYD so there is no confusion.

[2012ZL1]

Whats MG9? There is no MG9 on the order sheet. The manual trans is MN6.

[1BADZL1]

Originally Posted by 2012ZL1

Whats MG9? There is no MG9 on the order sheet. The manual trans is MN6.

MN6 code refers to the manual Tremec 6060 transmission, which is available in the Camaro, different versions of Corvette and our V.
Make sure you are not ordering a SS...
Very possible. I do not know why the correct RPO would not be reflecting the correct transmission. MN6 is found in SS I believe...
MN6 while is a 6 speed, is NOT the same gear set for ZL1.
Hope that helps.

[Rice Killer]

Thanks for the information MY68RS!

[garfin]

There are 2 codes that appear on each manual transmission vehicle. MN6 refers to the fact that it is a manual transmission vehicle and MG9 is the RPO code for the specific gearset used in the TR6060 for the ZL1 (and CTS-V).

Best regards,

Elie

[OldJedi]

ZL1 is supposed to get an MG9 HD 6 Speed manual.

[OldJedi]

Elie, I see you sold your 98 SS, are you getting a ZL1 ???????

[htron50]

Originally Posted by OldJedi

ZL1 is supposed to get an MG9 HD 6 Speed manual.

ALA 1969 Rock Crusher? Bet So! It's going to be a real monster tamer! You won't be able to hurt that thing.

I'm going with Auto simply due to physicial limitations, but, I will always admire the stick shift and the heavy duty nature of this one! Good going!

Let's ALL keep in close contact here as we go to get our Traditional Orders system modifications next week!

Have a GREAT WEEKEND ALL!!

[2012ZL1]

wierd. well the number on the quick order is definately MN6, so if that is the generic term for manual trans then I guess thats it..Auto is MXO

[garfin]

Originally Posted by OldJedi

Elie, I see you sold your 98 SS, are you getting a ZL1 ???????

Well, I sold the SS (and accompanying '97 Bonneville L67 winter beater) to get the V.
I'm holding my breath, waiting to see what price GM Canada puts on the ZL1 and will hopefully have an opportunity to drive one at some point in the new year.
I can't see keeping the V and a ZL1, so I guess I'll have to wait until a few more unknowns become a bit more clear to me. The V is one amazing car, but I've learned to "never say never"!

Best regards,

Elie

[OldJedi]

Originally Posted by garfin

Well, I sold the SS (and accompanying '97 Bonneville L67 winter beater) to get the V.
I'm holding my breath, waiting to see what price GM Canada puts on the ZL1 and will hopefully have an opportunity to drive one at some point in the new year.
I can't see keeping the V and a ZL1, so I guess I'll have to wait until a few more unknowns become a bit more clear to me. The V is one amazing car, but I've learned to "never say never"!

Best regards,

Elie

Well it sounds like the Caddy just became the winter 'beater' and the ZL1 the summer 'beater'. Just a thought. Stay Warm.