drifter5674

Auto Zone and Oriely is 282.00

drifter5674

Figured I might as well do the back main while I am there. Although it appears to be dry

drifter5674

What about the LUK clutch kit. Is it any better?

drifter5674

It is all quiet and no clutch chatter. Just slips under hard acceleration especially 4 gear and above. Considering leaving the original GM pilot bushing in.

Kevova

Alot of drama for a clutch kit. LOL. How are you planning to use car? Just a cruiser or some kind of competition? Just a cruiser most better name brand should work. Competition McLeod, Hayes, several the perfomamce oriented companies; of course the prices can more than double. Tracking will also steer you to a lighter flywheel. The idea is it's a one time thing, not that with practice you can get down to less than 3 hours. Because of my driving habits I wouldn't trust a standard replacement clutch to last.

drifter5674

Mostly just a week end cruiser. So I want it to be smooth and quiet. But I like to punch on it sometimes and chirp the tires. Just the 65 year old kid in me I guess.
LOL
Going to put in myself with help of my son, son in law, and grandson. I am sure they will only want to do it once. LOL
It works fine now. easy engage, no frogging and transmission is whisper quiet. But it has to be all the way out to take off and it slips under anything other than light acceleration above 3rd gear.
I bought it this way last Saturday. Or I should say the Boss lady bought it for me because she new how bad I wanted it. LOL
It is a 96 collectors edition coupe LT4 with Torch red interior 157000 miles. 164 made. Just could resist it.
C4's are hard for arthritic old man to get in and out of, but what the hell. It's a love hate relationship. Sort like being married. LOL

IBVETN2

[QUOTE=MatthewMiller;1599271208]These days every pressure plate replacement is sourced from China, probably from the same casting molds. No matter what they say, there's no evidence that a SPEC plate or any other is any different or better than the cheapest auto parts store plate (except that Centerforce attaches weights to the diaphragm fingers, but they have a bad habit of coming off). If the OP has an OE Valeo plate in the car now, I'd recommend that he find a shop that knows how to resurface pressure plates (gotta cut the pedestals the same amount as the friction surface) and reuse it.


This is unfortunately very true and the reason why I chose to resurface the friction surfaces on a dual mass flywheel and stock Valeo pressure plate when I did my zf swap.

drifter5674

From what I have been finding non are made in the US anymore. Most are from Mexico like Auto Zones clutch kit. Carolina clutches told me that LUK never built any clutches. They were Valeo sold in a LUK box. Maybe Mexico would be better than china but I suspect it amounts more about the quality control guidelines set by the retailer that puts their name on them.
Valeo is apparently the factory clutch provider or was for GM
Carolina clutch recommends shim kit to tighten up the pilot shaft in the transmission for the gear chatter when replacing DM flywheel with a solid flywheel. Also don recommend using aluminum flywheel

MatthewMiller

This is the route I would take now. Resurface the p/p, by a new disk, and try to find a NOS INA bearing.


The pressure plate of any kit is not cast in Mexico unless that's something really new. It would be a major deal if that were the case. Maybe it's assemble in Mexico after they get the casting from China? And I can guarantee the TOB isn't made in Mexico. The disk might be hecho in Mexico, but that's about it.

Valeo was the original supplier for the pressure plate and disk in the ZF-equipped C4s. They were really good units back in those days, either made in the US (at first) or Brazil (later in the production and replacement part run). But those days are gone. Even a new Valeo product is from China now.

Quote:

Originally Posted by Kevova

Alot of drama for a clutch kit. LOL. How are you planning to use car? Just a cruiser or some kind of competition? Just a cruiser most better name brand should work. Competition McLeod, Hayes, several the perfomamce oriented companies; of course the prices can more than double.

Again, to be clear: the p/p and TOB of every single new ZF6 clutch kit is made in China. Every one. It doesn't matter if it has a "better name brand" or not. They are all the same. The only exception is the Centerforce, which takes the same p/p and adds the little weights to the diaphragm fingers (which then often fly off while you're driving, LOL). I fail to see any reason to spend extra money on a "name brand" pressure plate when it's the exact same unit as the no-name unit.

Quote:

Originally Posted by drifter5674

Mostly just a week end cruiser. So I want it to be smooth and quiet.

The main key for smooth engagement (aside from proper installation procedures) is to use an organic disk. You don't need anything else in a stock LT4 that's being street-driven on street tires. You also won't want a light aluminum flywheel, because it will take more attention to engage it smoothly. For quiet, the heavier flywheel will help, too...or look into reusing the dual-mass flywheel that I assume is still in there. However, you need to make the flywheel choice before you buy a disk, because for the DM flywheel the disk needs to have a solid hub but for any replacement solid flywheel the disk needs to have a sprung hub. If you go with a replacement (solid) flywheel, then it is worth looking into the thicker shim kit, because you'll get some gear rattle.

TheGreek!

Every dual mass flywheel I've seen that has a decent amount of miles on it was severely "bowl" shaped on the friction surface. And I mean SEVERELY. When you take it apart I'll bet the wear grooves on the clutch disc are completely gone near the outer edge of the disc and still present near the inner edge of the disc. That right there will tell you that the flywheel is bowl shaped and I have yet to see a disc that isn't worn like that unless it has very low miles on it. If you just put a new disc in it and don't have the flywheel resurfaced the only part of the disc that will engage the flywheel will be the outer edge of it. On my '96 LT-4 car I replaced the flywheel with a steel single mass flywheel and put a sprung clutch disc in it and also installed the countershaft shim kit from ZF doc. If you don't install the shim kit with the solid flywheel the trans will make a horrible buzzing sound that will be so bad you'll think that the trans is about to fall apart. The shim kit is cheap and very easy to install, you don't have to take the trans apart to install it. It will still make a little bit of a buzzing sound but it will only happen at the beginning of 1st gear, at least that's what mine does anyway. Before I installed the shim kit it made a horribly loud buzzing sound in every gear during any kind of acceleration. If you resurface your bowl shaped dual mass flywheel a lot of material will need to be removed from it to make it flat again and now the surface will be even more prone to warp back into a bowl shape because the part of the flywheel with the friction surface will be much thinner than it was originally. Most shops aren't set up to properly resurface a dual mass flywheel and when you do find one that can do the job it won't be cheap to resurface it. Chances are the place that can do it will be far away and then you'll have to pay to ship the heavy flywheel to the shop and back and that won't be cheap either. You won't find a good used dual mass flywheel that isn't severely warped into a bowl shape unless you're very lucky and find one from a car that had it removed when the car was new to be replaced with a lightweight flywheel for racing. Don't get your hopes up on finding one with super low miles and not warped into a bowl shape, they're long gone.

anesthes

I just put a spec in my ZF6 car. It's a valeo pressure plate and their own disc.

They painted the pressure plate though, which is cool lol.

Make sure you get the correct TOB. Black tag = no insert, blue tag = nylon insert. Otherwise the bearing MAY move around/make noise.

-- Joe

anesthes

Yeah but you should never ever ever use a lathe to cut a flywheel in a performance car. We always used a blanchard grinder to cut a flywheel. (although now I just throw them out and buy new).

The dual mass flywheel has springs and stuff inside that also wear out. You're supposed to perform a test to see if it's got the same integrity as stock, and technically you are not supposed to cut them.

I'm running a SPEC single mass flywheel and a sprung hub clutch.

-- Joe

1990CONV

I have a 1990 with 33K on it. I bought the car in 1993. it always had a slight rear seal leak. I decided to fix it this winter. I was luck enough tha back in the 90"s I bought a brand new dual mass flywheel along with a new disk and pressure plate and had them in storage. I was surprised when i took it apart the the original flywheel and pressure plate still had all the original radial tooling marks evident. The disc even looked in great shape with minimal wear. I work for a high end inspection business and have a CMM at my disposal. For kicks I measured the taper across the new and old flywheel and pressure plates. To my surprise the original presure plate and flywheel had .019 inches of taper across the surfaces. There was minimal visual wear difference from the inner to the outer diameter. I then measured the brand new Dual mass flywheel and pressure plate. They both measured .009. The old parts came with the car in 1990. The new parts were dated 1995. I did see that the Dual mass flywheel was a superceded part number because there was some type of an improvement in the early 90's. Long story short I put is all back together and installed a fluted brass pilot bearing. The clutch behaves no different then the original but my rear seal leak is gone.

IBVETN2

[QUOTE=anesthes;1599288616]Yeah but you should never ever ever use a lathe to cut a flywheel in a performance car. We always used a blanchard grinder to cut a flywheel. (although now I just throw them out and buy new).

I don't have a Blanchard, but I stoned the surface to get a crosshatch pattern

The dual mass flywheel has springs and stuff inside that also wear out. You're supposed to perform a test to see if it's got the same integrity as stock, and technically you are not supposed to cut them.

easy enough to check, just rotate flywheel both directions and measure travel, should be less than 1.375

1990CONV

Not sure if a straight lathe cut or blanchard grind is the was to go. I thought I read somewhere years ago that they are cut on a taper for a reason. As I noted above in my post when I measured my brand new dual mass flywheel and pressure plate, both had a .009 inch taper in the same direction.I measured radially with a Coordinate Measurement Machine from the center out like spokes on a wheel. I took data every .12 radially. I am very confident that my measurements were very accurate. Maybe someone knows why the surfaces are not cut flat from the factory.

anesthes

I'm an engineer, so I usually go with RTFM. if GM says Blanchard, do that, If they have a special process, do that..

We used to use Blanchard grinders to cut flywheels. This was 15, 20 years ago. Now we just toss them and buy new ones. SFI flywheels are not that much money, and after witnessing a few clutch/flywheel explosions at the track my mindset is just totally different now.

For a track car I won't even use an aluminum bell housing anymore, and I always use an SFI flywheel in a track car regardless of horsepower.

9 times out of ten when they explode the go through the bell housing at 12 o'clock (I don't know why) but I've seen a few that removed the accelerator pedal before exiting through the dash... I like my feet.

-- Joe

IBVETN2

I don't believe that magnesium zf bell housing will stop an explosion. Exactly why I wrapped mine with an SFI blanket. I couldn't find any SFI bellhousings for the ZF.

1990CONV

I did a little research and supposedly there is a Valeo Tech Bulletin published that explains why the flywheel and pressure plate are concave. I have not loacted or read the bulletin.

anesthes

Oh it wont! lol.

I looked into this once about 10 years ago. Couldn't find a SFI bell housing either.

-- Joe

TheGreek!

I don't see any reason why it would need to be concave. How can you have full clutch disc engagement with a concave flywheel and pressure plate? The amount of concaveness I've seen on used flywheels and pressure plates is obscene, over an 1/8th of an inch. The wear grooves on the clutch disc were completely gone near the outer edge of the disc, worn down to the rivets but the inner edge of the disc was hardly worn at all, meaning, it was only engaging the outer edge of the clutch disc. There is no way in hell that's how it's supposed to be.