Clutch/Flywheel Replacement

Hi. I am an 18 year old owner of a 2004 Nissan 350z Roadster. I just purchased the car from a used salesman in Hillsboro, Oregon, no more than a couple of months ago. After purchasing the car, we had it inspected at the local Nissan Dealership only to find that the clutch was 95% worn, and the previous owner was from San Francisco. I was told that in order to replace the clutch I must also replace the flywheel, and that both should be replaced with Nissan?s OEM parts. While the clutch is inexpensive, $ 400, the flywheel comes in at a whopping $1,200. After much research I have become aware of aftermarket flywheels, which are single mass, lightweight flywheels around 18 lbs, that are significantly cheaper, $500. Given that Nissan?s OEM flywheel is Dual Mass, and weighs around 28 lbs, is it okay to use a Single Mass Flywheel, that is lightweight, or would this potentially damage the transmission, along with other driveline components? (The dealer also says that this can create serious vibration problems

A similar question was posted yesterday, with a couple of replies:

http://community.cartalk.com/posts/list/2116444.page

Haven’t heard anyone’s experience with replacing dual mass flywheels with solid mass flywheel conversion kits.

Why must it be replaced at all? These flywheels can be machined to like new condition for less than $100. I just did one on a Celica, and it was $56 to resurface it. And, they have no idea if it needs replacement until it is removed and inspected.

If you chose the lighter flywheel, you’ll not damage anything. The heavier flywheel stores more inertia, and makes highway driving more comfortable. It slows down less when the foot is off the gas. The lighter flywheel stores less inertia, and you’ll feel more engine drag at highway speed with the foot off the gas. It will only cause more vibration if it is not balanced properly at the manufacturer.

I know nothing about Nissan roadsters but I know a thing or two about BMWs which also use dual mass flywheels.

On BMWs, they cannot be resurfaced, and it is generally a good idea to replace them with the clutch because the clutch lasts around 150k miles and the dual mass flywheel probably won’t make it 300k miles, and they are a PITA when they fail. I didn’t replace mine, but I am cheap.

Lots of BMW owners replace the dual mass flywheels with lighter, solid flywheels. Yes, it does vibrate a bit more, not from imbalance, you are feeling engine vibration. The people who do things like that don’t care about a little vibration. You loose a little mileage as well. They don’t care about that either.

If cost is an issue, you can get a kit (Daikin brand) on line that includes your complete clutch and a solid flywheel for your car for about $350. You can put it in yourself if you are strong or you have a buddy to help you wrestle with the tranny.