DD clutch for a ZF6 What do you all use?

Powerstroke Cowboy · May 18, 2013

I am on the market right now for a DD Clutch for my ZF6. I will be doing a lot of Daily driving and towing with the pickup. This is what I mostly will be doing. But I still want to be able to hook to a sled and leave the line @ 4000 rpms and the same goes for drag racing. What do you all use and what do you use them for.
How do they respond to what you use them for.

I deal in South bend clutches so this is the way I am leaning BUT would still like to hear about the rest of them. I as of now have a Valair single disk clutch. The clutch shifts nice and smooth just does not hold the power.

Right now I am looking at the Southbend FDD32506 Clutch. On the South bend web page they say it is rated for 750hp. Has anyone tried it there?

Has anyone tried the SB FDDC36006 clutch rated for 850hp and how about the SB FDDC38506 clutch rated for 950hp?? These might be out of the question thou considering they are ceramic. Might not be good for towing or daily driving. But still would like to know what the ones think that have run them..

I aslo would like to know what you all think of the Valair DD part number NMU73DDZF6 rated for 650hp or the Valair DD SI clutch rated for 750hp. Part number NMU73DDZF6-SI.

Thanks for your time!!! AND you help. I would really like to get one before the sled pulling up here starts. The single disk I have now would hate me if I tried that sled pulling!!!

ON EDIT: Would even like to hear what you all have found out from using the triple disk clutches if there is any for the 7.3L ZF combination.

Thanks

....

jaybuller · May 18, 2013

I'm using a SB single, the one I got from you. But I've run in the past the 3250 dd. I loved it. Smooth as butter fr street driving lighter clutch pedal than stock too. Held anything I ever through at it. Even backing a heavy trailer was no problem at all. Buuuut I've never even ran my 7.3 all the way to 4000 rpms let alone try to launch at that rpm... I usually used to go at 2800 or so and run it out to 3200ish

lincolnlocker · May 18, 2013

i just put in a 3800lb dual disc with ceramic buttons in my 01 and its grabby as hell.... i dont have traction bars yet and prolly wont till i get a dana 80 in the rear.... i can try to slip the clutch on grass and it just chatters and shakes. axle wrap in the rear of this thing is horrible when on any soft ground.... my slip joint is almost shot and my rear ujoint is on its way out also... i hooked it to my 5th wheel the other day to bring it home from getting some repairs and it was parked in some grass and it did it even worse when i tried taking off slow and slip it a little.... so i put it in low lock till i got out on the driveway and that took care of it.... doesnt shift any better then the worn out stock clutch either but it grabs and goes when your not trying to slip it... i could start letting off the clutch and within a half inch to an inch and the stocker would already be engages, now with this new one its almost an inch or so from the top when it engages so i know i got the full movement back and i still have the stock hydraulics. i didnt change any of that while i was at it cuz i wanted to see if there was any difference... i do think that if i had trac bars it would help a ton... but as of now its not the greatest for towing.... i put it in because i am going to turn this truck into my puller... if its to grabby and not very slipable when hooked to the sled, i can change to feramic buttons or on up to kevlar..
its a diaphragm clutch from Kentucky clutch that was load tested at 3786lbs clamping pressure so it should do great hooked to the sled.

live life full throttle

Powerstroke Cowboy · May 18, 2013

jaybuller said:
I'm using a SB single, the one I got from you. But I've run in the past the 3250 dd. I loved it. Smooth as butter fr street driving lighter clutch pedal than stock too. Held anything I ever through at it. Even backing a heavy trailer was no problem at all. Buuuut I've never even ran my 7.3 all the way to 4000 rpms let alone try to launch at that rpm... I usually used to go at 2800 or so and run it out to 3200ish

Thanks for this information Jay. To bad you never tried high RPM launches!! LOL Are you saying you launched it @ 2800? or just ran it that high? This is the clutch i am most interested in right now. just do not want to buy it and find out it will not work for launches. would make me sick.

Thanks again.

On a side note. how is the new clutch treating you?

lincolnlocker said:
i just put in a 3800lb dual disc with ceramic buttons in my 01 and its grabby as hell.... i dont have traction bars yet and prolly wont till i get a dana 80 in the rear.... i can try to slip the clutch on grass and it just chatters and shakes. axle wrap in the rear of this thing is horrible when on any soft ground.... my slip joint is almost shot and my rear ujoint is on its way out also... i hooked it to my 5th wheel the other day to bring it home from getting some repairs and it was parked in some grass and it did it even worse when i tried taking off slow and slip it a little.... so i put it in low lock till i got out on the driveway and that took care of it.... doesnt shift any better then the worn out stock clutch either but it grabs and goes when your not trying to slip it... i could start letting off the clutch and within a half inch to an inch and the stocker would already be engages, now with this new one its almost an inch or so from the top when it engages so i know i got the full movement back and i still have the stock hydraulics. i didnt change any of that while i was at it cuz i wanted to see if there was any difference... i do think that if i had trac bars it would help a ton... but as of now its not the greatest for towing.... i put it in because i am going to turn this truck into my puller... if its to grabby and not very slipable when hooked to the sled, i can change to feramic buttons or on up to kevlar..
its a diaphragm clutch from Kentucky clutch that was load tested at 3786lbs clamping pressure so it should do great hooked to the sled.

live life full throttle

That sounds like one grabby clutch!!! I do not think that one sounds like a good DD and tow clutch. If A guy can get different buttons for them to soften it up a little might not be a bad way to go. I will look into there clutches and see what they have. I am looking at doing traction bars to keep wheel hop down and axle wrap. BUT i do not want to relay on that to make the clutch work better. Sounds like a good sled pulling clutch thou!

thanks for the reply.

jaybuller · May 18, 2013

yes I launched it at 2800 rpms. it was their street DD about 5 years ago. if I remember right it was rated at 650 hp. I could build the boost to about 20 psi and launch it hard as heck. never once slipped on me. I was running 250/100s at the time with a 38r. the clutch I had was also the "quiet idle" one that had the rubber nubs on the thing the floater plate hits so it didn't rattle like the old school dd did. not sure if they still have those but it was nice not having the dd rattle at idle with the clutch pressed in.

Powerstroke Cowboy · May 18, 2013

Sounds good Jay! If the information keep coming back good on that clutch I will go with it.
I would not be doing much launches or sled pulls with it. Maybe two or three hooks a year and maybe 10 or better drags with it. Just mainly diving around and pulling loads around the ranch. From what you say and I have read it sounds like a good clutch. Just might not be good for the power I would like to throw at it. Then again who needs more then what that clutch is rated for??

jaybuller · May 18, 2013

Just curious what kind of power are planning on making with that setup? very surprised you want to drag race with it. it was a slow shifting pig on the track with that clutch. I could launch in 4x4 high in 3rd gear and then only have one shift before I cross the finish so it wasn't to bad but I was getting beat by auto trucks with about 200 less rwhp. and I went through 2 zf6s before I quit drag racing it. the fast shifting really screws them up fast! I think it will be a very good clutch though for the occasional sled pulls and then using for towing the rest of the time.

jaybuller · May 18, 2013

have a question for you though... can you get a SB 3850 dd for a 12v nv4500 at a good price? my mud truck/puller project is in need!

Powerstroke Cowboy · May 18, 2013

jaybuller said:
Just curious what kind of power are planning on making with that setup? very surprised you want to drag race with it. it was a slow shifting pig on the track with that clutch. I could launch in 4x4 high in 3rd gear and then only have one shift before I cross the finish so it wasn't to bad but I was getting beat by auto trucks with about 200 less rwhp. and I went through 2 zf6s before I quit drag racing it. the fast shifting really screws them up fast! I think it will be a very good clutch though for the occasional sled pulls and then using for towing the rest of the time.

For now it will be around 600 or less. Really do not want to destroy the engine before i am able to get a engine built for it. After that maybe 700 to 750 on fuel. BUT that could be years down the road. I here you on shifting the ZF6 fast. its not going to happen. The ZF5 would be a better bet. were your drags in the 1/4 or 1/8 mile? It would be great to be able to hit the 100 plus mark in the 1/4 mile with a manual pickup or better. Would be hard thou.

The launches I was referring to were just in among my daily driving. Not a all out drag. Might only see thous 2 or 3 times a year to. Yea it would do better in the sled pulling world. Put in gear and let it eat.

jaybuller said:
have a question for you though... can you get a SB 3850 dd for a 12v nv4500 at a good price? my mud truck/puller project is in need!

I will have to take a peek for you. Thanks for asking. I will PM you the information.

nwpastroker · May 18, 2013

I'm runnin one of them, can't recal model, but it's 3600 plate load and bob ceramic, good for 750. I haven't pushed it by any means as I've only had stock Injectors in front of it. It's my first dd and I was very impressed with it. Very soft pedal, and stock like engagement. I had a valair single before that was rated at 600 and was all ceramic. In an obs with traction bars it would spin tire in parking lots trying to park, best way to describe it would be an " on-off switch" that being said, it held 250/100s no problem. I'm in the process of studs springs and 400cc hybrids as I type this, and will let you know how it hold with a little more ass in front of it

Edit- the dual disk is a soth bend btw, forgot to say that

Powerstroke Cowboy · May 18, 2013

nwpastroker said:
I'm runnin one of them, can't recal model, but it's 3600 plate load and bob ceramic, good for 750. I haven't pushed it by any means as I've only had stock Injectors in front of it. It's my first dd and I was very impressed with it. Very soft pedal, and stock like engagement. I had a valair single before that was rated at 600 and was all ceramic. In an obs with traction bars it would spin tire in parking lots trying to park, best way to describe it would be an " on-off switch" that being said, it held 250/100s no problem. I'm in the process of studs springs and 400cc hybrids as I type this, and will let you know how it hold with a little more ass in front of it

Edit- the dual disk is a soth bend btw, forgot to say that

If you new what part number your clutch was would really be nice! Sounds like it works really good for a DD clutch. Yes please when you toss more power to it please let me know what it does.

thanks.

nwpastroker · May 18, 2013

just looked up some info for ya.
Its a fdd36006

Powerstroke Cowboy · May 18, 2013

Thank you! Will take a peek at it.

psduser1 · May 19, 2013

I'm using a Kentucky clutch setup, behind for now, stock injectors. 3400# dual disc. I literally put it in, and hooked it to 14k for 1500 mi. That was the breakin.
It has a pretty stout pedal, and it can be grabby starting out, but I cannot slip it, no matter the load or throttle position! It's a straight organic face.
I think the grabby part could be avoided.

Cost was a lot better than south bend also, considerably less than a grand.

lincolnlocker · May 19, 2013

psduser1 said:
I'm using a Kentucky clutch setup, behind for now, stock injectors. 3400# dual disc. I literally put it in, and hooked it to 14k for 1500 mi. That was the breakin.
It has a pretty stout pedal, and it can be grabby starting out, but I cannot slip it, no matter the load or throttle position! It's a straight organic face.
I think the grabby part could be avoided.

Cost was a lot better than south bend also, considerably less than a grand.

where did you get the Kentucky clutch from? clutch dynamics by chance?

op, btw, mine is loud as hell at idle with the clutch pushed in.... i dont care what noise it makes though, as long as when i start throwing hp at it, it holds.

live life full throttle

Powerstroke Cowboy · May 19, 2013

psduser1 said:
I'm using a Kentucky clutch setup, behind for now, stock injectors. 3400# dual disc. I literally put it in, and hooked it to 14k for 1500 mi. That was the breakin.
It has a pretty stout pedal, and it can be grabby starting out, but I cannot slip it, no matter the load or throttle position! It's a straight organic face.
I think the grabby part could be avoided.

Cost was a lot better than south bend also, considerably less than a grand.

Another guy with a Kentucky clutch. You have stock injectors so they would not be much strain on the clutch. Have you ever tried to launch it at 3000+ RPMs in a higher gear?? If so how fast did it grab then? What is the clutch rated for as far as Horse Power and Torque?

Are you saying you paid less then a grand for the clutch or it was a grand cheaper then a Southbend clutch of the same design?

I will definitely be give these Kentucky clutches a hard look!

Thanks!

lincolnlocker · May 19, 2013

i guess i havnt tried any high rpm stuff with my truck yet(still stock inj)... i suppose i could give it a whirl though....

price wise, yes, a little cheaper, like south bends dd 3850 i found for $2300 and this one from kentucky clutch was originally $1500ish.

i did learn a few different things about some clutch pressure plate companies over the last few months about plate load and what they advertised it as and how far off some where...

for anyone reading this, stay away from centerforce unless your looking at a stock replacement....

also some say a lever clutch will hold better and the fact that if its a lever style clutch or a diaphragm style clutch wont be better or worse if the plate load is the same and the button material is the same, then it is going to hold the same, but the diaphragm plate will be easier to push....

live life full throttle

Powerstroke Cowboy · May 19, 2013

What is the Power rating of the clutch you got Lincolnocker???

lincolnlocker · May 19, 2013

dont know.... told them what i was using it for and thats what they said to use... its supposedly comparable the the south bend 3850. the button material is what will decide on the power it holds or takes... they said the ceramic should hold well and the feramic will take more abuse with slippage and hold a hair better, then the kevlar buttons is the best of all.. said if i cant make this one work with those choices, i would have to go to a centrifical clutch.

live life full throttle

Powerstroke Cowboy · May 19, 2013

ok Interesting. The Southbend dd 3850 one is rated for 950hp.... That is the strongest they make. They are less then 2 grand still a lot of money!!!

I will defiantly be looking into the Kentucky clutches!