[gapi]

I have been considering going from an open 3.06 to a Getrag 3.06 but am not sure its a necessity in my case as much as an obsession or for bragging rights.

I have a mildly Supercharged (7psi max) 2013 5.7L, stock manifolds into a Corsa CatBack. And an upgraded cooling system.
I have never ran it at a strip but am curious. I have even acquired a spare set of 2 wheels putting on Atturo Z850's for a trip to a strip this spring which I don't see becoming a habit. A total rookie at launching.

Traction control on this car seems to work damn well and I have yet to do a one wheel spinning launch or romp or in the wet. Even when press the TC button for a partial off.
When I play its rarely from an off the line.

I read a 2006 post about under heavy use the clutches and springs will wear out, which I'll not be putting one through, and get recommendations to buy used and replace with better aftermarket sets. I am capable of performing it.
In my research I read lots of posts on the Challenger forums about a common Getrag gear wine mostly in the 40mph areas.

So I'm thinking I may just want to pass on the notion. I wonder if since 2006 if the clutches have been upgraded in later units or if there any other side effects over an open diff.

Thanks

 

[Hemissary]

Using the PCM-based traction control system is robbing you of acceleration / speed as it tries to keep a wheel that has already started to spin - to stop. The PCM has to detect individual wheel speed first - then react by applying that set of brakes.

Note also that the ESP Off button never remove all traction restrictions; what remains still(!) prevents peg-legging, which would be an indicator you really do have more torque that overcomes tire traction. One way to overcome this is by installing a simple SPST switch into the B+ side of the Dynamic Sense module that resides under the console - just behind the shift mechanism (on the vehicle's CoG). Or, an aftermarket device that does precisely the same thing.

Only after you've properly negated traction control will you have a handle on whether you need a limited slip differential to prevent peg-legging...

Edit: no, the Getrag discs, plates and bell washers that apply the pressure / friction to reduce peg-legging are the same throughout. However, a replacement set that are spec'd for the Chevrolet version do offer more pressure / friction before breakaway.

Note: do not use friction modifier if you're interested in preserving that level of limited slip system friction. All the modifier is there for is to silence folks with dainty hearts and minds out there who hear chattering while turning tightly at slow speeds - which is causing the discs / plates to release-grab-release as the outside wheel travels a greater distance. The problem is - the friction modifier is allowing the assemblies to keep sliding against each other - once sliding starts (note; there is zero damage without the modifier).

 

[ChuckWagon]

∆∆ What Hemissary says above about peg-legging once you've disabled HAL completely. With the Getrag, you'll have a much more pleasurable steer by throttle experience... which some of us really care about lol.

I had a Getrag in my car for thousands of hard miles and dozens of trips down the quarter mile and no issues with the clutch pack. I didn't mind the gear whine either and eventually didn't even hear it.

The 3.09 in my car now got replaced under warranty in my wife's car and it whined so loud she couldn't take it anymore. Still whines in my car, but it hasn't gotten any worse in the last two years, so no biggie...If I don't want to hear it, I just ramp up the rpms and like magic, it disappears

Plus... ain't nothin like putting down two stripes that are hundreds of feet long.

I say do it, you won't be disappointed.

 

[gapi]

Thanks Hemissary & ChuckWagon

 

[CE9311]

I think I do well for a peg legger! I have found it interesting I have never seen my car do one wheel peel even though I 100% know she has a open 3.06 out back. I'd imagine dodge may still emulate an lsd in some form so charger bros can feel good. Or I just have little traction when I did it.

Although, it helps in the Pursuit, when I turn nannies off they actually turn off. I know the best 60ft I've managed was 1.984 with everything off, a light throttle launch and ginger roll (but quick) into the throttle to WOT.

 

[TheFrankenberry]

I can only say that if you're autocrossing or tracking (as in a circuitous road racing course) your Mope, get an LSD in that open diff! I had a Wavetrac installed in mine - keeping my tiny (er...lightweight?) 215mm axles and 3.06 gears - and the difference was NIGHT & DAY. No more constantly spinning out in the corners and I could finally come out of turns putting down all the power my puny 5.7 liters would allow. On a 60-second autox course it was good for 3-5 seconds.

The Getrag is a clutch plate LSD that comes with 226mm axles and 3.06, 3.73 (harder to find & more expensive) or 3.92 gears. It's an easy swap kit from MaMopar that is known to work reliably on the platform. Upgrading to a Ford 9" or some other type of center section can really open up your options for gears, diffs and axles. Like the OS Giken SuperLock LSD which itself has many options to specifically tune it to your needs.

I went with the Wavetrac because I liked the benefits I read about (like the performance & durability on tracked Beamers & Benzes). It's a helical geared ATB (automatic torque biasing) differential similar to the Blue Oval's Torsen or a Detroit Truetrac. However, the Wavetrac overcomes the zero-load peg-legging shortfall of other geared diffs via the unique feature found in its own name. The British Quaife diff is another choice available for the Mettingen(?)/Mercedes/Chrysler H215 empty pumpkin.

 

[gapi]

I had a Wavetrac installed in mine

Interesting. I had no idea of these. I have however experienced TrueTrac's in a hunting buds 4x4 truck front and rear across 17 years in all kinds of conditions from ice, mud snow, frozen gravel black top, rocks, and was always impressed.

I will look into these. I just need the occasional help in this area. Thanks

 

[gapi]

I wonder which is fasted to react in a launch? The Traction control, or WaveTrac? Would the WaveTrac be by default be putting even traction between the R & L tires leaving traction control off duty?
Or would traction control need to be disabled after converting the a WaveTrac? How much variance does traction control need to see before acting?

 

[Hemissary]

I wonder which is fasted to react in a launch? The Traction control, or WaveTrac? Would the WaveTrac be by default be putting even traction between the R & L tires leaving traction control off duty?
Or would traction control need to be disabled after converting the a WaveTrac? How much variance does traction control need to see before acting?

Not sure how to respond really; you definitely want the onboard / PCM-driven traction control system to be absolutely totally off...no matter what (individual wheel slippage is addressed by the FCM applying that particular brake system). Not a fair comparison really cause the Wavetrac system is supposed to negate wheel spin, whereas the TC system is responding to wheel spin.

Regarding the Wavetrac; you might consider doing some searching on here. They quickly fell out of favor as a result of difficult / finicky setup and assorted failure modes at relatively low PWR loading.

 

[gapi]

Copy that, thanks. I'm definitely digging into it. I have plenty of time, laid up with fractured knee cap right now.

 

[ChuckWagon]

Copy that, thanks. I'm definitely digging into it. I have plenty of time, laid up with fractured knee cap right now.

Ouch...I've had both knees scoped twice each and had injections for arthritis done a bunch of times, so I can almost feel your pain. Hope you heal up quick!

 

[TheFrankenberry]

Regarding the Wavetrac; you might consider doing some searching on here. They quickly fell out of favor as a result of difficult / finicky setup and assorted failure modes at relatively low PWR loading.

Hrm...

I've had my Wavetrac 5 years years now and it's been used hard (autox, track, winter) with nary an issue. Install was done by HHP in Delaware. I don't at all recall claims of them being problematic in my research at the time. There were, however, some regarding the Quaife unit and many about the Getrag.

It's important to note that the H215 center section itself is a PITA as it was never a Chrysler servicable part so no parts were ever stocked for it. Dealers only removed the unit and replaced with another - it's why the factory service manual doesn't list a specific bolt pattern, torque specs or particular RTV for the diff cover. I also remember the 3.23 & 3.55 ring and pinion sets from Richmond Gear definitely having install issues and/or breakages. Therefore a good drivetrain shop was absolutely vital to a successful LSD transplant into the 215mm open diff.

Most LXers are into drag...racing, so diff upgrades were kept simple with a DIY(!) Getrag swap which also gave stouter axles. The steeper gears were also more appealing for their super short runs down a strip. I think that's a better explanation of the Wavetrac's poor popularity in the LX community more than anything else.

 

[Hemihackman]

Gapi, I could recommend putting in a Getrag rear. You may already have the updated axles. I first put 3.23s in my open stock 2006 R/T from Richmond. The tolerances on the German rear were tight! Then later swapped in a complete rotor to rotor rear cradle from a 2013 SRT8. That was a 3.06. I swapped in a 3.73 Getrag from a wrecking yard. Fluid was black so I took that apart and installed Z06 clutch pack from Tasca parts. Big difference with LSD and trac off.

 

[Hemissary]

Also talk to Hell Raiser Performance...

 

[gapi]

Thanks Guys for taking the time, All very interesting! MUCH Appreciated.

I have really been digging. I see full Getrag component kits, Hubs, (not required but recently have been hearing one of mine) Axles, Diff, Bolts $2566.00 shipped best quote so far. East Coast Moparts. The Getrag splines are not the same as my H215.
Its been suggested to get a used Getrag to save $$ and upgrade the clutches but I'm shy of that route.

The Frankenberry words on parts for the H215 chime quite true as I would want to replace the carrier bearing sets and finding them was a chore unless I wanted to take a chance on cheesy vendors getting China fakes. I did find them though. I found out if you order the Cup & Cone by each its twice as much as by ordering as a set p/n. NP604623 90KA1 & NP957403 90KA1.

FYI, I'm a long in the tooth industrial maintenance hand and machinist having performed lots of critical power transmission setup work. I must say I find the H215 snap-ring lash adjustment method kind of lax. Cannot find the lash specs anywhere either. The 200 is .003-.006.

Whatever I put back there it will not be tortured or called upon often. I'll not be adding more power. I have been running the same type of build (Maggie Blower @8psi & Corsa Cat Back) on my 2005 Silverado L33 5.3L since new @5kmiles and remain content. The same will be for this R/T.

Thanks Again

 

[gapi]

Possible Reason For Some of the Wavetrac Failures?

Possible reason for some of the Wavetrac failures could be setup? Just mulling this WaveTrac thing. I know the Getrag swap, I already swapped out my 2.65 for a 3.06 open to open.

About me calling the lash adjustment on the H215/200mm Lax, like The FrankenBerry points out, MOPAR doesn't service the H215 nor does the service manual give specs or procedure on rebuilding it.
So I looked at the 200MM diff instructions seeing the the Differential housing "Spreader". Damn! Across more than 30 years I have done tons of setup for clearance and pre-load but never seen housing flex factored in to achieve preload.

I have seen a few uTube videos of people just slapping them in and racking the ring gear against an indicator and get happy. I always wondered about the side loading.

In a nut shell you load the unit into the housing with the cones on, slip the cups in getting a snap-ring on one side installed.
The other snap-ring may not be able to access the groove.
Then take the slack out of the spreader adjuster and setup a dial indicator on the spreader to the housing @Zero and apply the spreading to exceed no more than a 0.012" spread.
Install snap ring and let off on the spreader looking for a retained housing spread of 0.007-0.009" for proper side bearing preload using different snap-ring thicknesses if correction is required.

Some may not be side loading properly or at all.

Like I said, "I'm still "Digging Around". Going this route would have me fabricating a spreader because they are not cheap. And I am the resident Machinist OTJ.

 

[Hemissary]

Ring / pinion setup traditionally, has always(!) been extremely important to longevity, even from years and years ago. Setup requires patience and very careful measuring. Noise during operation has also traditionally been a pretty good indicator of a problem.

 

[Hemihackman]

Chrysler doesn't give service parts for the Getrag either- other than seals. Unitrax in Cal. has bearings and diff clutches though. I used that same spreader when I put 323s in the 210.

 

[gapi]

Copy that thanks.
Another thing I bet some neglect is even with the side pre-load being setup correctly to get proper ring/pinion backlash and not take away from pre-load you have to keep the same amount of shim thicknesses involved.
Example, if you have a .005 snap-ring on each side totaling .010, and need to move it over .002, you decrease to .003 in that direction and increase to .007 in the other. Some may be just doing one side adjustments.

 

[gapi]

You may already have the updated axles.

Thanks, Just found out you are correct. The 2009 Challenger R/T manual trans shaft upgrade was from the 27 hub spline hub axles to the 32 which I already have.