Manual Tranny

[Tanreall]

Guys I want to know your opinion on the 89 manual transmission. I'm thinking about buying one but I never hear any comments on them. Also what are the gear ratios on it.


Thanks in advance.

 

[JonM]

Guys I want to know your opinion on the 89 manual transmission. I'm thinking about buying one but I never hear any comments on them. Also what are the gear ratios on it.


Thanks in advance.

IMHO...Sports Car = Manual Tranny

 

[c4cruiser]

The 89 manual gearbox is a ZF 6-speed. ZF is a german company that makes high-quality and very strong transmissions for a lot of high-performance european cars. Corvettes used this box up through 1996 in all their cars (including the ZR-1) until the C5.

They can be expensie to repair, but parts have become available to the public in the las couple of years. Used to be that a dealer or only a few tranny shops could get components. The ZF uses a special gear oil that you get from GM or you can use a Castrol 10w-60 motor oin that is usually available from BMW dealers. Following the service recommendations for gear oil changes will insure long life.

The 6th gear in a Vette ZF is normally used for hiway cruising for the best fuel economy. Top speeds are attained in 5th.

ZF tranny Vettes use a dual-mass flywheel and cluthc/pressure plate designed for it and they can be expensive to replace as part of a cluthc job. some folks go to a more standard flywheel/clutch/pressure plate design when they do a clutch job.

Some gear noise is normal with a ZF. So if you hear a little bit of noise at lower speeds, it should not be a big deal. Regular service will keep it working just fine.

 

[Tanreall]

Thanks a lot for the info.

 

[C-4 Now]

89 manual transmission

I have a 6-speed 89 transmission have had this car since 95. Transmission hasn't given any problems but has always been a little noisy. The 89 cars sometimes have a nosiy flywheel which my car has had for a while. The latter cars I have drove don't seem to have this problem and the transmission seems quieter but the hp/torque rating for the latter transmissions is not quite as high. The only other problem I've had is the hydraulic clutch system of which mine is now leaking and will have to be fixed this spring.:cry I may also change flywheel at this time? The plus is I really enjoy driving this car for fun and whenever we take a road trip mileage is great! Hope this helps.

 

[8388]

Gear ratios - 1st-2.68, 2nd-1.80, 3rd-1.29, 4th-1.0, 5th-0.75, 6th-0.50, Reverse-2.50

 

[Tuna]

The ZF6 in my old 92 has 105K+ miles on it and it's still going strong - even with an additional 75 HP added to it.

 

[Skant]

The ZF6 is a blast. Just an absolute blast. Very good set of gear ratios. Strong as heck. The only drawback is you hope you never have to repair it. It's expensive to work on.

I don't list the mild noise as a negative factor because it's not unpleasant, and it actually helps you sense your speed and gear without having to watch your gauges. Just like the vette's typically noisy tires, rough road feel... the whole car gives you a lot of feedback on what's going on, and that's very useful to performance driving. You really don't want the car to be numb when you've got your foot in it.

 

[8388]

To me, the perfect ZF would have a .85 in 5th and a .68 in 6th ratio. .50 in 6th is way too much.

 

[Skant]

Not if you put in 3.73 or 4.11 rears...

With a stock rear end, 1st gear is a little high, too. All of the gears are too high.

I think the ZF6 was intended for the rear gear swap. Give it a mild rear end so it can pass government requirements... and then enthusiasts can put in a more aggressive rear... it puts 1st - 6th in all the perfect ranges. 1st - 4th become great ranges on the track. And 5th and 6th move to exactly the right spots for freeway cruising.