Here I am

Cerametallic clutch

Attention: TDR Forum Junkies
To the point: Click this link and check out the Front Page News story(ies) where we are tracking the introduction of the 2025 Ram HD trucks.

Thanks, TDR Staff

SPDiesel Transmission Controller

Still waiting on the banks exhaust brake release

I have had the SBC 13" upgrade Con OFE in my 97 for over 36k miles. I took the transmission out a few weeks ago to replace what I thought was a bad pilot bearing but turned out to be the input shaft. To get to the pilot bearing as you know you have to remove the pressure plate and clutch disk. To my surprise the clutch disk was hardly worn, and there were NO grooves in either the pressure plate or the flywheel. I use this truck as my work truck and also to pull our 30' 5th wheel.

What I found tells me that this clutch is good for another 40k+ miles. Sure you are saving maybe $400 on the purchase. . but will it go the distance???? This clutch is one more thing I dont have to worry about...





Rick
 
I got to jump in on this one.



I have had a older LUK Pro Gold and with less than 10K miles on it, I was slipping it first only in 5th and then 4th and then 3rd. When I first started slipping it I got a hold of my supplier and they in turn gave me the # to LUK. After a very short time listening to me they told me that I had done something wrong installing it. Then I asked to talk to the manager and got another run around. I then went to Peter and South Bend and started with the older Con B, it didn't slip but had other issues and with one call and less than a minute I had the then new Con O coming my way no question about my install. Now two clutchs later I have the latest clutch for us HP junkies. South Bends DD w/ 3850lb Pressure plate.



In my book along with quality is standing behind one product and Peter does this almost too well:D



Any large company that sits back letting the smaller one do all the R&D and then coping there product sucks in my book.



I just spent better than $7800. 00 and countless amont of time rebuilding my motors and I would not put anything less than a South Bend behind it.
 
here's a recent post from our own respected Joseph Donnelly:



"LuK has to satisfy a lot of preferences of buyers who are not diesel enthusiasts, let alone b. o. m. b. ers. The stock clutch in the '04 is very smooth and holds a "reasonable" amount of power. LuK has spent a good bit of time on their new cerametallic clutch, but they have not been able to get the kind of accurate testing with high horsepower Rams, especially towing heavy trailers, that is needed to validate its effectiveness and determine its limits.



South Bend does not slam LuK, in fact some of their best clutches use LuK pressure plates [worked over a bit, to be sure ] and disk hubs. Careful attention to geometry for the best clamp load (pressure) curve over the life of the clutch, and choice of the most appropriate friction materials set SB clutches aside from the pack of clutch resellers and rebuilders. Their customer service is legendary here on the TDR.



In the next few months I plan to have some testing completed on the new LuK cerametallic. I have heard that earlier prototypes had the typical teething pains of slippage etc. but this one may be good, resolve the holding and drivability issues common to new clutch designs, and fill a niche for Rammers who need more clutch than stock. Believe it or not, Peter is also interested in it because he wants us to get the best values for our applications, but he is rightfully cautious pending results of testing.



Meanwhile, the more expensive SB Con FE has established a loyal following because of its holding power, durability, and heat resistance in a clutch that has smooth, stock-like engagement. I was more than impressed by the con FE performance at MM'02 where "Sparky" Yardley abused it unmercifully while pulling the sled, yet it still held! Whereas brass alloys soften (melt) around 1500-1900 deg. F, iron is good to 2500 deg.



Our options in clutches today are vastly improved over what was available when my '97 was new. I still like the redesigned Sachs with brass/ceramic pucks and high clamp load in my '97. I recently removed it to find the wear was quite modest after three years. However, for my 2004 I want a clutch more in line with the personality of the new truck--lighter pedal pressure, smooth engagement, yet good holding power. I have driven a Ram with the Con-Fe and it has those features. Testing continues!'




Thru my 50 years or so of vehicle ownership, I have selectively found and regularly used a fair number of products that have been found to work extremely well, for ME...



BUT, I was told many times my use of a Frantz toilet paper oil bypass filter would ruin my engine, and all that TP would end up down in my crankcase...



AND the oil return up into the valvecover FROM that filter would cause oil foaming and cause an engine runaway from the vapor it creates...



And the STP I've used for years is "snakeoil" that will clog up and ruin my engine from all the accumulated sludge that evil STP creates...



Then, there's my error in using those damaging fuel additives for added lubricity that will soon destroy my VP-44 - that is, IF the slightly higher fuel pressure from the added Carter pusher pump doesn't get it first...



NOW, I guess, I'll hafta add my selection of the LUK Cerametallic clutch to my long list of "mistakes" - golly, it must be a miracle that NONE of those nasty things have occured, and that all my vehicles and engines have lasted so well, and I have NEVER been left afoot alongside the road because of engine or drivetrain failure.



I must live a charmed life! :rolleyes: ;) :D :p



Often, a potential customer has to look beyond what is the "most popular" or has a large cult-like following, and make the best selection that seemingly applies best to THEIR situation and needs - I could have waited 6 months to afford the SBC I have great confidence in - at the END of the RV towing season on an already slipping clutch - or go NOW with a less costly one that SEEMS appropriate in price and ratings for my situation. Retired, and on a fixed income, SOME decisions of this type ARE dictated largely by price - and all we can do is make our choice and hope it was one that won't come back to haunt us - I've done quite well in this regard in the past - and hope my winning streak continues! ;)
 
Last edited:
Gary: I am waiting for your run down on the install. I have a SBC sitting here watting for me to install. So tell us about your expierance. You dont have a 4X4?
 
The install went smoothly enough - I've done this before several times - but on "standard" clutch setups in passenger cars and hotrods - the Cummins/5600 are in a class of their own! ;)



Sticks has posted step-by-step instructions on doing the job in another thread, look for it, I can post a pointer here for you in a little bit. The instructions are a help, there are a few things I would add, and some of the order of attack change slightly - but it's still a good start.



Yes, mine is a 4x2.



The hardware all looks excellent, the final result is a clutch engagement that is slightly more positive than the stocker, but not aggressive or unpredictable - it feels as tho' I get slightly better clutch disengagement, which has totally eliminated the common light tendency to "catch", or grind when shifting into 3rd gear when the transmission lube is cold - and reverse and low gear are also noticeably easier to engage at a standstill as well. SO far (WAY too soon for reliable judgement!), I like it quite a bit...



Good luck to you on yours.



(EDIT)



Here's the pointer I promised:



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=101709
 
Last edited:
OH - and as the the slight change in the order of activity, *I* suggest that immediately after getting the truck up in the air and located where it will be during the clutch swap, IMMEDIATELY place the transmission in 5th gear so the output shaft can be rotated when reinstalling the transmission to line up the splines into the hub of the new clutch, then remove the shift lever assembly while you are still clean as to not grunge up your truck interior with crud from rolling around under the truck in your yard or garage floor.



ALSO, you hafta totally remove the plastic console from the transmission hump - I didn't realize that and wasted some time atttempting to get to the shifter bolts thru the shift lever boot area... :rolleyes:
 
Gary; thanks for the help. Ive got Sticks instructions plus a shop manual. I know I can do It but I am trying to cover all the bases. I am going to rent a heavy trans jack for 25$ a day. Two days ok. Also I am planning on surfacing the fly wheel. 50$ here in SR Thanks again Jim
 
The only addition that I have to Gary's tips is that make sure you check the play in the input shaft. If there is much side to side play you might consider doing the input shaft kit. That big bearing that holds that shaft gets a lot of work.

I thought I had a pilot bearing going out but it turned out to be the input shaft bearing. .

I guess after 215k on the stock transmission... its time for things to get loose...



Rick
 
Peter,

Questions; 1. What is my stock clutch made of in my 92.

2. What is the friction coefficient, breaking point and melting point of my stock clutch?

3. What is the strongest(?) clutch I can run in my truck without modifications to the flywheel?

Kurt
 
Kurt, your 92 has a Sachs with cast iron pressure plate cover and organic facing with fiberglass in it. It has a large surface area to dissipate heat, but like any organic, the resins will "boil out" between 350 and 400 deg. F. you can run any clutch with that bolt pattern--meaning the 13" Sachs and the 12. 3" LuK, and variations on that. If the stock Sachs is not holding up, and you need more torque capacity with smooth operation, call South Bend. The modified Sachs I use in my 97 (as another example) is not so smooth and is best reserved for very high hp street applications.



Mark Chapple has done some testing recently on the LuK Cerametallic, as Peter said. If the wear is indeed 5. 5 times as rapid as the con Fe, that is serious. Not because you will possibly have to replace the flywheel when replacing the disk and pressure plate--LuK sells a replacement, OEM-grade flywheel now, or you can get one from Cummins. If you gotta have the power, cost is secondary when buying a clutch. More importantly, the "sweet spot" of disk thickness for a diaphragm clutch is pretty small. If overall thickness changes a lot from wear, the pressure will go down, and torque capacity will be substantially reduced.



Over time, probably less than a year, we will hear more about the cerametallic Luk facing and its wear characteristics. For the interim, TST's findings are most likely reliable and representative.



It is sort of amusing to call LuK and South Bend competitors. LuK is a huge supplier of clutches to OEMs like Dodge, with a smaller aftermarket division. South Bend is a comparatively tiny shop, working hard to produce specialty clutches for a few "niche" markets.
 
Luk's clutch

After suffering through all the negative comments on th Luk clutch, I purchased mine this morning. It is being overnighted to me, since as of this morning I have had to shut the engine off twice in order to get out of gear. Haven't had any slippage problems, just disengagement which means, more than likely, pressure plate. I, like some others, am driven by value for dollar spent. If the ceramettalic scores my flywheel before the next change, that is something I can live with. You can turn the flywheel a lot of times for the $500. 00 difference. :)
 
In response to some questions about the Luk HD Cerametallic clutch, Mark Chapel (owner of TST) is running the Luk HD Cerametallic in his 03 6spd. I sold him this clutch knowing he has a heavily modified truck with impressive hp/torque ratings. I personally want to know what the upper limits of this clutch is and who better to deal with than Mark. I have spoke with Mark several times since the installation and as of yesterday he is not only still running the clutch, he has been impressed with the driveability of a clutch capable of holding the power he is generating. Mark also informed me he recently let a customer, who is in the market for a clutch, drive his truck and he was equally impressed. Is this the clutch for everyone? Maybe or maybe not. All owners have their own preference as to what they want and what they want to spend and who they want to deal with. I am not here to question anyones integrity, ethics, or quality of product customers and vendors alike. Luk makes a quality unit and has been doing so for years.
 
"as Peter said. If the wear is indeed 5. 5 times as rapid as the con Fe, that is serious. "



C'mon Joe you, and the REST of us are smarter than to get beffudled by a statistics "numbers game"!



5. 5 times *WHAT?* :rolleyes:



IF the SBC clutch wears a flywheel 10 thousands in it's lifetime, that means a LUK would do 55 thousands in the same period - are EITHER of those figures anywhere NEAR accurate for flywheel wear - OR of serious concern? Some here are tossing around stats and claims like they are Gospel - without the slightest documentation!



Has ANYONE actually TRIED and documented the melting point of the LUK Cerametallic? Or are we merely dealing with wild assumptions? Do *any* here actually KNOW what the alloy content and percentage of ceramic IS in the LUK? I sure have serious doubts that LUK will simply offer up those specs to anyone who wanders in and ASKS for it!



"It is sort of amusing to call LuK and South Bend competitors. LuK is a huge supplier of clutches to OEMs like Dodge, with a smaller aftermarket division. South Bend is a comparatively tiny shop, working hard to produce specialty clutches for a few "niche" markets. "



EXACTLY! And the quaint notion that LUK somehow must follow any outfit such as SBC to "steal" their ideas is laughable - if it wasn't for LUK, where would SBC even get the pressure plates THEY use in their own kits? :rolleyes:



"If you gotta have the power, cost is secondary when buying a clutch. More importantly, the "sweet spot" of disk thickness for a diaphragm clutch is pretty small. If overall thickness changes a lot from wear, the pressure will go down, and torque capacity will be substantially reduced. "



YUP - and exactly HOW do you INCREASE the applied pressure in a pressure plate? As *I* understand it, you do it by altering the fulcrum point - BUT, the problem with THAT is that doing so ALSO changes the applied pressure curve over the lifespan of the clutch - most manufactures seem to design the pressure plate to apply slightly reduced pressure at the beginning of a clutches life, gradually INCREASING it as the disc nears mid-life, then tapering off slightly as the clutch nears the end of it's lifespan.



Theory states that altering that same pressure plate to create higher pressure at the BEGINNING of the discs lifespan then creates a situation where that applied pressure slowly but IMMEDIATELY deteriorates as the clutch the wears thinner - it's a simple matter and choice as to whether you prefer decent clamping pressure over the whole life of the clutch, or mostly at the beginning - there's NO "free lunch"!



I enjoy a good debate as much as the next guy, and a small degree of speculation MIGHT be OK - but wild claims, unfounded statements and outright distortion of fact CAN get out of hand.



My LUK is fine so far - might go TU tomorrow - but as a fairly active member here, I've seen my fair share of clutch failures and problems with ALL makes, including SBC's stuff - none of them are sacred or fault free - and to be bluntly candid, if I sell my stuff for nearly twice that of the competition, I can dern well afford to send out an occasional "free" one to keep customers happy.



And I'm STILL waiting for a response to THIS question:



"Only one valid question remains as to comparing the $550 LUK vs the $900+ SBC Con Ofe - the LUK was represented to me to be good for in excess of 500 HP. , if that is not correct, who wants to challenge LUK's claim? And, if the price comparison is not fair or proper, what clutch similar in power rating to the LUK *does* SBC offer near the $550 price of the LUK?'



Anyone? ;)
 
Last edited:
Sure,,, I'll do a back-to-back testing of a Ceramtellaic to a Con FE.



I have an FE right now. After I put 20,000 Miles,, good or bad, yielding any major problems with the ceramettalic, I'll pull my FE out, and put a cerrametallic. I'll give yall a comparison.



I've always been loyal to SBC. Peter is a great guy. Persoanlly,, I don't think the Ceramettalic will hold a light to the FE. but I'll keep my eyes open.



So far, my FE is good. It's slightly grabby, and can slip with a redlined 3rd gear slipping start,, but it only has 150 miles on it.



Merrick
 
"I've always been loyal to SBC. Peter is a great guy. "



YUP, but this isn't a popularity contest - I highly respect Peter and his product too - but this is about the relative quality of 2 competing clutches, including price differential - when I have to make a choice between keeping my family fed, or a distant faceless "five-tiered" sales structure, *I* will hafta choose my family every time, all else being equal!



Get back to us with your test - THAT is more to the point of this discussion than whether Peter is a "nicer guy" than Tom... ;)
 
Has ANYONE actually TRIED and documented the melting point of the LUK Cerametallic? Or are we merely dealing with wild assumptions? Do *any* here actually KNOW what the alloy content and percentage of ceramic IS in the LUK? I sure have serious doubts that LUK will simply offer up those specs to anyone who wanders in and ASKS for it!



Yes in fact they have. The friction companies themselves. Luk does not have any facility to make clutch facings so they rely on the very same companies that we do. There are only a few clutch facing companies in the world. And they all have their charts and graphs to show all of the curves. The facing company that I use out of Canada not only makes the Feramic material but they make matallic, cardotic, and many others. So Gary, no, I didn't just pull them out of a hat. These figures are very important to us and help us to decide what material is best suited for each and every application.



EXACTLY! And the quaint notion that LUK somehow must follow any outfit such as SBC to "steal" their ideas is laughable - if it wasn't for LUK, where would SBC even get the pressure plates THEY use in their own kits?



Luk and the Luk after market are two separate companies. Luk after market does not manufacture any clutch components. They purchase From the manufacture and alter them same as us. Will they copy someone or something that is known and working? You bet they will. I earlier mentioned Valeo who is twice the size of Luk OE and they bought straight from us, out of France, our kevlar pilot brg. that we designed for the Ford Diesel. They may very well go OE with it. They also parroted a clutch conversion design of ours. Gary, this is common because companies such as mine get the opportunity to see the aftermath of the OEM designs and flaws and repair them, that is if they are innovative enough to do so. Yes, OE provides us with a base but it is what we do with it that counts.



Peter
 
[
QUOTE]Only one valid question remains as to comparing the $550 LUK vs the $900+ SBC Con Ofe - the LUK was represented to me to be good for in excess of 500 HP. , if that is not correct, who wants to challenge LUK's claim? And, if the price comparison is not fair or proper, what clutch similar in power rating to the LUK *does* SBC offer near the $550 price of the LUK?'






This is my thoughts exactly that is why I bought a LUK from Carolina Clutch and I thought long and hard before making my decision. But when it came down to it I made my decision as I always do What is the best product for the price?? Not what is the best product or the cheapest price, but the best for the dollar spent. I am sure I would have a better warranty with SBC but the way I see it, It was not worth $400 for that warranty. Is there $ 400 difference in product ?? I did'nt think so
 
Last edited:
Originally posted by Gary - KJ6Q

[- when I have to make a choice between keeping my family fed, or a distant faceless "five-tiered" sales structure, *I* will hafta choose my family every time, all else being equal!






Let's not be overly dramatic here. We are after all talking about all kinds of unnecessary and discretionary modifications to our trucks. You could have left it stock and then wouldn't have *any* extra money tied up in it.



I understand your point, but as for the drama :rolleyes:



I am interested in seeing more about the "newcomer" though. It's always good to have options.



Mike
 
Back
Top