Heavier duty clutch?

[nvrenuf]

Tom is right, I ran a clutch from a C40/50 application for a long time with no problems. The disc looked like the one pictured on the Hayes box in Rene's post. The pressure plate was brutally strong, so much that it caused the firewall around the master cylinder to flex.

I wish I had some real tech to add but I never paid attention to the disc center piece.

Kevin, what do you do with the Suburban? Pull anything crazy? Does it see an excessive amount of vibration from a lot of lugging?

 

[u2slow]

Its my service 'van' - I'm an electrican. I don't even have it fully setup yet. Its 6000# now, and probably 1000# or so yet to come.

I don't tow anything.

It does see lots of miles - sometimes in aggravating traffic, which does tend to make me drive it harder. I've driven stick for 12 years (since I was 18) mostly in fullsize GM trucks. Changed several clutches and engines. I've never seen this kind of failure before.

It was making a fair amount of drivetrain noise leading up to this - which I thought was the driveshaft steady bearing. But on disassembly, the trans, steady bearing, and even the rear end all check out.

 

[tarussell]

I thought yours was four individual pucks rather than the style on the box ???

Tom

 

[tRustyK5]

Tom is right, I ran a clutch from a C40/50 application for a long time with no problems. The disc looked like the one pictured on the Hayes box in Rene's post. The pressure plate was brutally strong, so much that it caused the firewall around the master cylinder to flex.

I wish I had some real tech to add but I never paid attention to the disc center piece.

Kevin, what do you do with the Suburban? Pull anything crazy? Does it see an excessive amount of vibration from a lot of lugging?

The Hays I have is pretty stiff through the clutch pedal...even with the hydro clutch stuff. I'd say it's easily as stiff as my old diaphram clutch with the mechaincal linkage. It's not as bad as the old Borg & Beck leg breaker I used to have though. I can't imagine how the Hays would be with mech linkage...

Rene

 

[nvrenuf]

I thought yours was four individual pucks rather than the style on the box ???

Tom

Mine was more than 4, maybe 6 or 8. It for sure wasn't continuous like the one pictured in post #19.

 

[nvrenuf]

Could the pilot or transmission input bearing be failing? Just thinking that since it's not seeing a lot of shock loading (dumping the clutch, etc) maybe something is allowing the input shaft to wobble/vibrate excessively/etc causing it to try to move the disc while it's engaged.

 

[u2slow]

I've given the input shaft a wiggle. Also had the top cover off the trans. Nothing looks or feels amiss.

I intend to change the input bearing before it goes back together as a precaution. Might as well change the pilot bushing also - odds are a fresh one comes in whatever kit I buy.

 

[DEMON44]

Mine was more than 4, maybe 6 or 8. It for sure wasn't continuous like the one pictured in post #19.

As I said before.........thats my flywheel. the clutch disks look nothing like that.


They have 6 distinct ceramic buttons on 6 paddles.

Misalignment on the trans to engine would take out a bearing in a hurry. Doesn't change that is a shockload failure. A mild shock on a bad disk, who knows.

 

[DEMON44]

To avoid falling further into crazyworld.........this is my clutch layer by layer

 

[Shawn]

I had the Center Force Dual Friction behind my 496ci. Worked awesome! A few members here reported I had my front wheels come off the ground when I did a 5k clutch drop in a parking lot.

I could still feather it if needed. It wasn't an on/off type of racing cutch.

 

[nvrenuf]

That's some crazy lookin junk there Demon44! What's it fit?

I've got a dual disc clutch for my K5 but it's nothing like that.

 

[DEMON44]

Its a Southbend 13" DD 3600 plateload ceramic with 1 3/8" input. behind a Cummins in front of the NV4500. It'll put up with slipping, the beauty of ceramic. Perfect for Boosted launches at the track or mild sledpulling.


after injectors and twin turbos I'll threaten it's limits too. maybe have to go to a 12 puck ceramic or feramic and higher plateload.

 

[DEMON44]

I keep looking at that picture and your description, in my head keeps pointing to a shockload failure. but the hub fixture must have been faulty. Because I beat the living TAR out of the stocker in my dodge and never had it fail (until I burned it up when I bumped the power output).

My stock disk was 12 1/4" disk 1 1/4" input shaft my truck weighs in at 7200lbs unloaded. it had 2 stage damper springs too......very similar to your setup there.

 

[slyguy_22]

whats a decent clutch for my sm465 that wont break my budget but performs well?

 

[u2slow]

I keep looking at that picture and your description, in my head keeps pointing to a shockload failure. but the hub fixture must have been faulty. Because I beat the living TAR out of the stocker in my dodge and never had it fail (until I burned it up when I bumped the power output).

My stock disk was 12 1/4" disk 1 1/4" input shaft my truck weighs in at 7200lbs unloaded. it had 2 stage damper springs too......very similar to your setup there.

Your stock disc has 2 stage damper springs... mine does not. The southbend and Luk pro-Gold setups for the 6.5TD look like your stocker.

If by shockload you mean the torque/velocity spikes associated with each cylinder firing, I agree with you there. There was no particular driving incident I can recall where there was any change in sound or feel. When it finally gave out it was uneventful.

 

[DEMON44]

Yours IS identical 2 stage like mine.........you see the springs inside your springs. Mine are just separate. same same though.


I meant shock load by means of blunt force trauma..........but if not. Makes me think faulty disk more so. No sudden shock, only 10,000kms........manufacturers aren't perfect.

 

[u2slow]

Yours IS identical 2 stage like mine.........you see the springs inside your springs. Mine are just separate. same same though.

I disagree - IMO your stock clutch has far more dampening ability. Southbend trades off clutch surface area on the 6.5TD to use that style of damper hub. I think I see springs inside springs also.

I haven't put hands on one to be certain, but I think there are essentially 3 parts or rings, each moving semi-independently based on the spring-rate. Sorry for the shoddy description - I hope you catch my drift.

 

[DEMON44]

Your sort of splitting hairs now, you have 2 stages of spring and I had 2 stages of spring. just oriented slightly differently..........


now say even if your disk had double the dampening ability. If you never shockloaded it, you'd never bottomed the springs and therefore never damaged the hub. Your engine doesn't have the power to bottom those springs even if you dumped the clutch. Its sort of engineered that way right. The force required to bottom all of those springs at the same time far exceeds the max output of the engine in a given application. would only make sence right to prevent damage......much like you have.

Take it apart and measure the force neccissary to bottom on fat sping and one skinny spring. multiply each by 5 and add together. That'll be the engine torque required to bottom all the springs. I'd bet those are near 100lb short fat springs. and 50lb long skinnys. OK maybe 75 & 35 being a little more realistic. I think the 'ol 6.2 is a long ways off that either way.

You don't need more dampening, you need a non-faulty disk IMO.

I dynoed 262RWHP and 650ftlbs on a chassis dyno through my stock clutch., dumped it more times than I can count. and never hurt it. yours can't be that much weaker than mine was.

of course this all just IMHO, thats just how it adds up in my head.

 

[u2slow]

You don't need more springs just a better clutch. Centerforce maybe.

I asked around and got a 12" Centerforce II disc for comparison. Placing them side by side, the damper hub looks IDENTICAL to my shattered one.

So no, not going that route.

Going to check on some 6.5TD dual-damper stuff later tonight.

 

[Slapperbar]

Well, I did say "Maybe."