Those with ceramic DD, got a question [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: Those with ceramic DD, got a question


blctalon
03-24-2011, 08:49 PM
Ok, so I decided to try the Valair over Southbend. What I purchased was a Ceramic DD clutch rated to hold 650hp/1400ftlbs or something like that. I went with the stronger DD ceramic clutch they had to offer after reading about how people were slipping their singles. That and the fact I didn't want slipping clutch issues.

I have about 500 miles on the clutch so far with no issues. My only complaint is the noises since the thing is a solid hub. I knew there would be noises, but I didn't know the kind of sounds and when they would happen. I must say they're pretty obnoxious but I'm getting used to them.

I'm only running a 40hp tune but the clutch seems very strong and definitely doesn't slip with the gas pedal mashed to the floor. I've yet to feel the slack clutch pedal issue I had before which was believed to be from overheating clutch fluid.

So here's my question for the guys with dual ceramic discs. Is your clutch pretty grabby? Gentleman at Valair advised me to take off in 1st and try not to slip the clutch for the first 300-500 miles which is the break in period. He said if I didn't do this the clutch could glaze over and never smooth out. So far it hasn't smoothed out any. Taking off in 2nd results in a little buckage unless I do it quickly - the saying I've heard going around, "it's either in or out" seems to hold true. Do these things ever smooth out over time? Sure is hard backing up slowly.

The other thing I'm worried with now is googling around brings me to the dodge forums where guys are talking about their valairs. They claim a guy named Dan told them not to tow with a ceramic disc. This sort of bothers me because I told them what I was doing with my truck over the phone and which clutch I wanted and they never mentioned a thing about not towing with it.

tysmith
03-25-2011, 08:26 AM
You'll be fine towing...
Noise, that's it, especially with a solid hub. Its noisy with sprung hubs, I can't imagine solid disks. I had South Bend strap my floater, and it is as quiet as a single - you do still get the growl from the trans in neutral - that's gear rattle.
It won't get any less grabby. when backing to trailers, a lot of guys put it in 4low (that have 4wd). If I hooked to trailers a lot, which I don't, I'd wire in a disconnect to disable front axle so I could have 2low, but I very rarely need to back to a trailer.
Your driving style will improve. I've had a dual disk for four years or so. Its funny driving my dad's cummins with a single - like driving a car!

I can't speak for Valair, but South Bend is a GREAT company to deal with. Hopefully you have plenty of trouble free miles with your Valair. :driver:


Ty

blctalon
03-27-2011, 09:41 AM
Thanks for the reassuring comments. The neutral rattle is annoying but the one that makes me grit my teeth is the "lug growl" or the noise you get if you sort of lug the vehicle down around 1200 rpms. I used to take off in 2nd, hit 4th, then 6th. This driving style gets me 18.8 mpg city driving. Its hard to do it now and listen to all the noise rattling under my feet. I don't really understand what causes all the noise. I suppose it's the floater plate vibrating around until the discs speed up? You'd think it would do it all the time and not at just low rpms.

I went fishing yesterday and towed my boat with the truck. Didn't have an issue pulling at all. I used all 6 gears from start to finish. Clutch pedal never got slack or stiff. My tires were chirping from time to time taking off in 1st then switching to 2nd. When I got home backing the boat under shelter was a bitch. I had to use 4low and I was still bucking around. I have to feather the clutch to get it under the shed because my t-top barely clears the beams of the structure so if I'm off to one side too far it can hit. Anyhow, I'll be rattling all the way home until this thing breaks.