RAM 5.7L HEMI TC Vane angles vs KJ TC

gmctd · **Posted:** Wed Oct 29, 2014 3:33 pm

Exactly - which is why the 5.7l Hemi TC produces lower stall on the 2.8l KJ than on the Hemi - reduced power = reduced ability to overcome the increased hydraulic coupling with increased vane angles = lower stall, i.e., more effective hookup = more kick-in-the-pants - some appropriately specific torque figures in nm and ftlbs are in early posts back in ought 7 - lessee if I can find one.....................

Remember, everyone who has installed one, or had one installed raves about the improvement in driveability - those dealer-installed TC's also receive rave remarks from the dealer and techs

I had to bite the bullet and spring for the SUNCOAST version, simply because nothing was known on the 'net about their source - only after I began my investigations, and seeing the stock Hemi versions listed on eBay (saw one for $8.95 with $50 shipping from 5.7l RAM owner with SUNCOAST upgrade), did I regret paying so much for a unit for the street - new across-the-counter at the dealership was only ~$178.00, back then, but who knew?

Specifically, I am NOT detracting in any way from the SUNCOAST version - it's just too expensive for a simple street upgrade intended to improve driveability, which is the goal that most usually financially-strapped owners are attempting to achieve

Ennyhoo, lemme see if I can find those torque figures - I'll be back........................

Auberon · **Posted:** Sat Nov 01, 2014 4:16 pm

Thanks Gents. Very interested in your writings re this.
Have re-re-re-read as I've been mulling this over at length for some time.
Not scared away by the K factor / jargon. Background assists in that area. I get that K is a necessary constant used to act as a gauge for the coupling efficacy of the rotor stator assy in order for the results to be interpolated to other applications provided other data ties in and removes the seeming dependence of some to be fixated on a number rather than a behaviour. Also recognise those numbers are snapshots but what else can I use? I could well upset my perfectly happy little KJ doing the rolling chassis dyno work by holding with foot brakes and then releasing her high in the rev range as she starts to slip. I figure this is a test to do when I have the new pump and TC to hand. :wink:

Did some seemingly appropriate probing, delving and the seemingly correct permutation of the Hemi TC fits in 1 listing I found to 304 vehicle fitment applications and in another some 132 vehicle variants of which Jeep comprised 16 variants from 2004-2006 with .......da da daaah! My exact model, year and specs etc.

Given that I utterly do not dispute what my compatriot who regrettably resides on the other side of this large country has penned about his experiences with this installation on this Forum when I re-visited his posts in the way-back machine. I am poised to proceed sooner than expected, possibly maybe.

Would like to play with the numbers and do the maths. I'll work those numbers the Greendiesel chaps generously provided into my fiddles (given the formulae aren't that hard to get around and understand) about stalls and the other performance parameters I may be able to get a handle on for a definitive (at least for me) decision.

I fully understand how the critical the smoothing role as a dampener is a TC - just as the springs in a manual driveline are designed to buffer against the harsh cyclical / pulsing loadings of combustion in a simplified combustion cycle as opposed to the less shocky and somewhat smoothed effect as the number of pistons increases. After all we don't exactly have the biggest dampener/flywheel for smoothing the combustion jolts of this torquey little engine.

As one wise man wrote quite recently (WWdiesel) numbers exact or not - they are close - Stock 300 ft lbs (406 NM); Mopar Euro TC rated 400 ft lbs (542 Nm); and Suncoast - 1ESTC rated @ 600 ft lbs (813 Nm). That, in my book makes the first 2 in the list not candidates at all. Given the known Torque that the V8 job will take this warrants considering especially given its respective pricing per unit. A stock TC is currently available on ebay just a few suburbs away from me for too much money.

My time to action this is fast approaching and rather than, as some have suggested - use it and see if you get shudder / problems then build in a TC that is appropriate the question remains to be a boy scout and be prepared. I don't engineer that way EVER. I try to cover all bases before they happen. As an old systems engineer I can do nought else. Until I run the numbers and here more from those I respect I won't be happy.

That doesn't mean I am still not VERY interested in what gmctd and GDE have further to the gold they've already sent our way so far.

gmctd · **Posted:** Sat Nov 01, 2014 4:30 pm

Those "wiseman" numbers were merely copied from earlier posts way back in ought 7\ought eight - IIRC, see retmil, ranger1, maybe GDE, nursecosmo, mrmopar, and etc for original and more complete torque data for the engine and 545RFE transmission -

I'm dyslexic with numbers - can spot a misspelled word clear across a mall parking lot but numbers beyond two digits are confusing, resulting in many misteaks, so any correct numbers in my posts are contributions from tenured members...............................

A manual trans flywheel is of necessity a larger item to achieve the rotational mass - that mass is easily achieved in the auto-trans system within the much more bulky torque convertor, therefore requiring only the much lighter flexplate\starter ring-gear for attachment to the engine P.T.O. hub

However, a 4-cyl Diesel engine is always much more forceful in it's exhibitionistic display of "combustion jolts" and power thrusts

lars0247 · **Joined:** Sat Oct 12, 2013 12:09 am **Posts:** 98

gmctd,
Could you please tell me how you wired the manual TCC switch?

Thanks.

gmctd · **Posted:** Sat Dec 13, 2014 6:25 am

lars0247 wrote:

gmctd,
Could you please tell me how you wired the manual TCC switch?

Thanks.

Hi, Lars

Unfortunately, it's not that simple - TCM monitors the solenoids for correct impedance, will flag DTC if incorrect

The TCC solenoid is Pulse Width Modulated PWM, meaning it is not a simple on\off control, like the old T350 and 700R4 trans series
- a variable-frequency signal is applied to a current-driver which drives the solenoid
- low-freq = narrow pulses, solenoid valve is effectively off
- increase frequency = increasingly wider pulses, solenoid begins to activate, wide pulses = solenoid is full on
This is variable to match TCC apply to variations in driveline loading, as in towing, done to improve fuel economy

The TCC is also controlled by a switch activated by the brake pedal, such that any application of braking releases the TCC - this is done to prevent stopping the engine in sudden full braking panic stops

A TCC control switch would have ~4 dpst circuits, or two spst and two dpst
- to switch-in a test solenoid for the TCM to monitor
- to switch-out the in-transmission solenoid
- to connect the solenoid to the external variable-frequency driver circuit
- to connect the line pressure signal to the variable-frequency control

Line pressure signal must be monitored for connection to the PWM drive circuitry to control pulse width

In addition, the line pressure signal must be juggled to achieve correct increased apply-pressure, so as not to aggravate TCM into flagging a DTC when TCC apply is desired, but not commanded by TCM

I did this sometime back in ought 8-9, and I've slept some since then, so there may be more
It is a complicated circuit, and I seem to remember a glitch or two, so it may not be ready for prime-time at this juncture

Hemi · **Joined:** Sat Dec 13, 2014 12:57 am **Posts:** 3

I currently have a 2005 2.8 CRD that has had the updated Euro TC and the latest software programming. It also has the full torque eco tune and has been working great for the last 9 months or so. Recently it developed the TC "shudder" while under load at low RPM. I was not surprised to get this based on what I have read so I installed a new Hemi TC and front pump in the trans to rectify the issue. Unfortunately, it is exactly the same. I then had the shop (I work at a Jeep dealership) reexamine the complete transmission to make sure there was not another issue besides the TC and everything checked out just fine. I also spoke with GDE and we discussed trans programming and his only thought was to go to the Suncoast TC as his programming gives the TC more lockup and would only exacerbate the shudder issue. For lack of another option I am now going to try the transgo shift kit and the Suncoast TC and hope the issue is resolved. In short, the hemi TC did not take care of my shudder issue as I hoped it would. I welcome anyone's thoughts or what worked to resolve their issue.

gmctd · **Posted:** Sat Dec 13, 2014 12:52 pm

Might be best to try the TRANSGO kit first, SUNCOAST later - TC is not always cause of or solution for shudder

Shudder should be most often felt in TCC lockup, which is direct-coupling to engine, no slip (resulting in EURO TC with increased spring tension in clutch disk hub) - TC is fluid coupling out of TCC lockup, not normally known to transmit shudder into drivetrain

Could be pressure flutter when valving-in second front pump

Could be winter fuel related

Could be deteriorating injectors

Since you had shudder before upgrades, could be defective liquid-filled engine support (they leak), required to reduce vibrations - if one fails and sags, can cause bad driveline angles - both failing causes even worse
- could even be rear transmission\transfer case rubber support causing bad driveline angles in the swb KJ chassis
- transfer case configuration results in additional weight off-set to left of drive-train center-line, not to mention front differential left offset
- driver (nut behind the steering wheel) weight is additional offset on left suspension points

Could be defective cross\bearings (u-joint) in rear driveshaft, exascerbated by sagging transfer case mount

Could be worn rear driveshaft yoke, tailshaft-housing bushing, or output shaft splines in xfer case

Could even be deteriorated suspension bushings in the rear axle mounting scheme, resulting in bad driveline angles

Could be front sag caused by worn ball-joints - V6 K3199's are best replacement for the lite-duty 4-cyl versions oem-installed in the Diesel KJ

Could be worn front-drive half-shafts, which are not disengaged in 2wd

Could be worn\deteriorated rubber isolators in the exhaust system hangers

Could be deteriorated flex isolator at the soot-trap\catalytic convertor

The '05's are at least 10yrs old, next month...................

gmctd · **Posted:** Tue Feb 03, 2015 9:17 am

GreenDieselEngineering wrote:

The torque curves for GDE tunes are done on a dyno, where we can hold rpm constant and snap a measurement once the engine has stabilized. In real life driving this is not feasible as the converter is slipping and passes through the rpm band quicker than the turbo can spool. The turbo lag is why you notice the kick in the pants.

I would have to ask the engineers at Chrysler about the hemi TC. That was plan of record at the start of the KJ program development. However, the converter was changed to a 150k stall with a 2.3 multiplication ratio. Sorry for the terminology, that is what the designers used. I am fairly sure the hemi TC had a 180 or 200k stall. We do not use a "stall speed" in rpm, since this is dependent on engine output horsepower. The k factor eliminates hp from the equation.

One of the reasons for the design change was due to the diesel torsionals in a 4-cylinder engine, which are considerably higher than the V8 hemi in the 1400-2300 rpm range.

As I tho't: they wanted more slush to prevent 'lugging', mild with the V8 but exaggerated due to only 4-cyls in the KJ - would've caused many non-resolveable warranty complaints amongst the projected customer base: chicks and soccer-moms'n'dads

The KJ 2.8L will have lower stall with the Hemi-verter than the 5.7L due to lower developed power - so, us manly-men should know what steps are necessary to prevent excessive lugging with the desired increased hydraulic coupling

Mountainman · **Posted:** Thu Feb 19, 2015 3:07 pm

well, I was sold on Suncoast, until I realized it was WAY more than the Euro, so I bought a Euro, but haven't had time to install it. So, now I read all of this, and wish I had the Hemi TC :banghead:

Anyhow, please correct me if I'm wrong, but stronger hook-up, is effectively less slip when not locked, and this will correlate to significantly better mileage when unlocked? I spend a ton of time off-road where I can only dream of locking the TC (I don't want to mess with a pulse width modulated solenoid despite my electronics background) at such low speeds, but it seems that the Hemi TC would be a nice upgrade, and doubly has less rotational mass than the Suncoast for the highway??

Thanks for all of the info in here! Too bad I didn't see these Hemi TC discussions a year ago :dizzy:

rancherman · **Posted:** Thu Feb 19, 2015 8:00 pm

Mountainman..
I'd say the Hemi TC would do what you think.. slightly better hook during unlock. The angles of the vanes are set up for big torque at a much higher rpm.. for the gasser. our lil guys are much lower rpm when the max torque is built.

The euro's should be basically the same as our NA models, during unlock.
For the life of me, I cannot understand how a stronger hub spring has anything to do with a TC slipping. I can see it keeping the hub 'centered' during torsional whiplash.. but in no way would it help the piston apply more pressure, or the frictionals hold more effectively.
The one way I can see it helping out is; on a weaker hub dampner, the torsonals won't bottom out the springs, causing a 'end of the road' type shock back to the clutch itself... which could certainly over power/torque the static holding power... just to wind up and start again!
All drivelines < as a whole> are big springs under tension.. from the motor mounts clear to the tire patch on the ground.
I look at it the same way as we all can lift and carry 100#s. Try that when someone drops the same load in your waiting arms from a height of 10 feet

My hemi tc is on the shelf for now.. I'm going to install it this spring when I tear into the jeep for a lot of other maintenance.

Mountainman · **Posted:** Thu Feb 19, 2015 9:40 pm

Thanks Rancherman, that's great news! The extra dollar a gallon for diesel is killing me, but with the turbo compensating for altitude, I think this Jeep still has the potential to massively outdo the mpg of my old toyota, which runs super rich at the altitudes I drive (I'd guess 12mpg).

WWDiesel · **Posted:** Thu Feb 19, 2015 10:21 pm

Mountainman wrote:

Thanks for all of the info in here! Too bad I didn't see these Hemi TC discussions a year ago :dizzy:

I totally agree Mountainman! If I had been aware of the merits of the Hemi TC a year ago, my CRD would have a Hemi TC in it today in the place of the SunCoast. Absolutely nothing wrong with the SunCoast TC, it is one very great TC, but it is pricey!
As some have already stated on here, I believe the SunCoast TC might be a bit of an overkill for the problem we are trying to solve. (Shudder in lockup) If I were replacing my TC today, it would be a Hemi TC.... :roll:

Live and Learn! We all evolve as we learn better options to modify these little Diesels...everyone benefits from the experiences and testing by others! :wink:

Mountainman · **Posted:** Fri Feb 20, 2015 1:00 am

well, I guess I'll consider myself lucky then, because my life was too crazy to get it installed. I luckily read this thread just before install of the Euro. Now the only hard part is dumping the Euro... $250 anyone? :ALONE:

rancherman · **Posted:** Fri Feb 20, 2015 9:51 am

Mountainman wrote:

Thanks Rancherman, that's great news! The extra dollar a gallon for diesel is killing me, but with the turbo compensating for altitude, I think this Jeep still has the potential to massively outdo the mpg of my old toyota, which runs super rich at the altitudes I drive (I'd guess 12mpg).

LOL.. my 94 'yo 22re is NOT the fuel mizer I'd thought it would be.. It's the ranch's gofer/knock around vehicle. Basically a covered 4 wheeler with heat and radio! On the best, very best conditions, 22 mpg @ 55 mph is all I've knocked out. (downhill with a tailwind)
I give 330 for my TC, delivered to my door. That included the core, which I will not return. (It's gonna cost almost as much to ship back as what the core is worth... plus the fact the part numbers do not match) Most of the online mopar parts houses are about the same price.
this is one example http://stores.revolutionparts.com/autop ... r4736587ad

Mountainman · **Posted:** Fri Feb 20, 2015 3:31 pm

Yeah, that's what my old 86 4runner is. Drive it right down 4wheeler trails through the brush to load up an elk or whatever. It might get 20mpg at 55, but it's a bored 30 over engine with a performer cam.

Mountainman · **Posted:** Fri Feb 20, 2015 3:57 pm

thanks for the link, man they are cheap compared to the Euro that I have sitting in the garage :furious:

flash7210 · **Posted:** Fri Feb 20, 2015 4:22 pm

Here is a re-man for under $150
http://www.ebay.com/itm/DODGE-JEEP-45RFE-545RFE-Trans-Torque-Converter-HD-for-1999-2006-13-37-/261505163703?pt=Motors_Car_Truck_Parts_Accessories&hash=item3ce2ec21b7&vxp=mtr

Mountainman · **Posted:** Fri Feb 20, 2015 4:41 pm

hmm, I don't see them listing a specific part # :banghead:

I'd email them if I hadn't just ordered the 4736587Ad for $306 shipped :5SHOTS:

WWDiesel · **Posted:** Fri Feb 20, 2015 10:02 pm

Another view:
To add more info for TC consideration. From a fellow CRD owner and friend:

Ron (Suncoast) stated in April 2007 that he developed the Liberty CRD TC by starting with the already developed SunCoast TC for the Ram Hemi truck. not a Mopar unit. There is a major difference in build quality in those 2 parts. Even then, it took 3 months to develop, test and tune it on a Liberty CRD at their HQ in Fort Walton Beach, Florida.

Having seen both the Mopar and SunCoast TC disassembled, they bear little resemblance inside, or outside for that matter. Not much at all. One is $35 worth of the cheapest looking parts I've ever seen and the other looks it came out of a Sherman tank. When Chrysler cuts quality to subpar even on stator and valve body/pump regulator springs, you know their TC's have been plundered and pillaged.

No way I'm convinced a Mopar Hemi TC is worth even $50, much less $300.

Make your best choice based on the available information....

gmctd · **Posted:** Sun Feb 22, 2015 12:54 am

The large number of DODGE RAM 1500 5.7L HEMI trucks having been observed thru the years sitting immobilized on the side of the road with ever-expanding puddles of ATF+4 underneath would certainly seem to lend credibility to that statement, eh................... :ROTFL:

The oem stock Hemi-verter, as do all oem torque converters, has stamped steel drive\driven covers, oem friction clutch material, drive\driven turbine vanes are located in place by folded end-tabs, and cast-aluminum stator - all proven entirely suitable for normal heavy-duty hauling\towing service - over many miles of usage, the friction material is usually the first failure resulted by normal wearing-thin

The SUNCOAST Hemi TCC was 'hardened' with a machined "billet" drive cover\integral TCClutch drive plate to prevent warping, the TCClutch disk gets KEVLAR friction material to prevent slippage, the turbine drive\driven fins are "brazed" as in any fluid coupling for hi-power hi-rpm thru-put, and some other stuff, like maybe increasing the number of sprags in the one-way stator clutch, possibly a new "billet" aluminum stator, all done to handle 450~600hp^ @8000rpm in repeated trips down any 1/4mile drag strip, and reliably survive the jaunts

The SUNCOAST unit is a good upgrade, no doubt about that - would have been particularly so during the early chronology of the original KJ TCC, which had a thermo-plastic stator assembly that easily shattered in normal driving scenarios, resulting in much warranty repair rework during '04-'05 until the F37 upgrade was issued for a revised TCC with an aluminum stator upgrade
Some pics of an opened KJ TCC were posted, showing what was left of the shattered stator assembly, plastic shards erratically distributed amongst the turbine fins

No such failure occurred in the Hemi trucks - the SUNCOAST upgrade was required because the oem TCC could not reliably transfer upgraded Hemi V8 power to the drivetrain, as shown in a picture of an opened Hemi TC with burned and warped drive plate surface - the new "billet" drive cover with thicker\wider drive plate surface prevented the burning caused by slippage with subsequent warping of the thin stamped-steel drive cover producing even more slippage in lock-up

So, gentle readers, if anyone's KJ 2.8L CRD is capable of outputting those levels of power in that rpm range, then it would be time to seriously consider selecting the SUNCOAST over the "flimsy" factory Hemi TC - which, BTW, was designed to handle way more HP, torque, and rpm in stock form than the KJ CRD is capable of outputting even with any of the variously available ECM upgrades

Yes, I upgraded to SUNCOAST based on member Ranger1's valued input, but back in ought 7 that was the only known option at the time - subsequent investigations on my part revealed the oem stock Hemi-verter as a viable option for those not planning on repeated 450-600hp 8000rpm short-tripping jaunts down the asphalt

A number of eye-witness owner-type testimonials on this forum have proven that to be true, I think - let your wallet be your guide

RAM 5.7L HEMI TC Vane angles vs KJ TC

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