Cracked Pressure Plate

**Coyote** · 01-25-12, 03:50 PM

While reassembling my LT4 I was in the process of installing the flywheel, clutch, and pressure plate. I noticed a small hairline crack in the pressure plate housing. Now I'm thinking that since the engine is out that it would be safer to replace rather than have it come apart in the future. There were no other symptoms with these components. No telling how long it has been this way. Any advice?

**K & B Special Products** · 04-10-12, 11:18 AM

Pretty obvious, replace it or your foot.

**Coyote** · 04-11-12, 07:58 AM

I ended up replacing the pressure plate. Problem is that I could not locate an OEM pressure plate. I found what I thought was one from a company on the Internet. I ordered it and then about 30 minutes later I got a phone call telling me that that specific part was no longer available and that they could not guarantee exactly what brand would be shipped. As predicted, the pressure plate they sent was made in !@#$%ing China! I installed it and got everything back in the car. Now the engine has a vibration at high RPM's. I know that the original pressure plate and flywheel were balance as a unit. In hindsight, I should have taken the flywheel off and had them balanced before installation.... we live and learn.

**K & B Special Products** · 04-11-12, 08:22 AM

Sorry to hear about your trouble. The correct PP kit explains the balance procedure. We still have a couple of USA clutch kits available, if any one needs one.

**93Rubie** · 04-11-12, 05:38 PM

You should call/email Jim at Power Torque Systems, L.C. He has the info, knowledge, and supply for whatever you need for the ZF6.
He has the good stuff, all LT1/LT4 pressure plates currently on market come from China, doesn't matter if it is Autozone or Spec, or anyone else, all Chinese castings. You will pay for a good one, FYI.

**K & B Special Products** · 04-12-12, 08:26 AM

Originally Posted by 93Rubie

You should call/email Jim at Power Torque Systems, L.C. He has the info, knowledge, and supply for whatever you need for the ZF6.
He has the good stuff, all LT1/LT4 pressure plates currently on market come from China, doesn't matter if it is Autozone or Spec, or anyone else, all Chinese castings. You will pay for a good one, FYI.

Sachs, GM's current supplier, is a German company. Also LUK has great clutch components.
You are correct re: price, but not that much. Discounters use the overseas suppliers. I doubt the new ZR1 clutch is made in China, or any other late model 6 speed with a warranty.

**93Rubie** · 04-12-12, 09:14 PM

Originally Posted by K & B Special Products

Sachs, GM's current supplier, is a German company. Also LUK has great clutch components.
You are correct re: price, but not that much. Discounters use the overseas suppliers. I doubt the new ZR1 clutch is made in China, or any other late model 6 speed with a warranty.

Pretty sure the OP's 96 LT4 is out of warranty and is NOT a new ZR1.

89-96 ZF S6-40 stuff that is high quality is hard to find. See this article written by Jim.
http://powertorquesystems.com/Corvet...ngtheC4MN6.pdf

I have yet to see a NEW DM Flywheel, OEM clutch disc, OEM Pressure Plate, etc....that was NOT NOS. They simply don't exist anymore. GM is NOT making them or supplying them. Pretty sure LUK and Sach's don't supply/make any NEW production available currently OEM equivalent quality ZF 6S-40 parts. If you know of some, please tell me I would snap them up.

**K & B Special Products** · 04-13-12, 08:30 AM

Originally Posted by 93Rubie

Pretty sure the OP's 96 LT4 is out of warranty and is NOT a new ZR1.

89-96 ZF S6-40 stuff that is high quality is hard to find. See this article written by Jim.
http://powertorquesystems.com/Corvet...ngtheC4MN6.pdf

I have yet to see a NEW DM Flywheel, OEM clutch disc, OEM Pressure Plate, etc....that was NOT NOS. They simply don't exist anymore. GM is NOT making them or supplying them. Pretty sure LUK and Sach's don't supply/make any NEW production available currently OEM equivalent quality ZF 6S-40 parts. If you know of some, please tell me I would snap them up.

I've got 2 new kits for $350 each. Start snappin'.

**93Rubie** · 04-13-12, 04:03 PM

Originally Posted by K & B Special Products

I've got 2 new kits for $350 each. Start snappin'.

Really?
Who makes these?
I assume clutch disc, Throw out bearing, and pressure plate?
For the Dual Mass or is it for Single Mass?

If someone has started production of these and they are quality.
I'm sure lots of others would like to know as well.