Picking up a M6 Hellcat

[16GoManGoHC2]

Yeah I’m going to get the car up in the air and take a look at everything (just to make sure there are no surprises) and then I’ll likely take it to the dealer and let them take a look. It still has some powertrain warranty on it, I’d assume that’d be covered.

It makes the most noise when I’m at a stop with the car in neutral and my foot off the clutch pedal. The minute I engage the clutch, the sound goes away, that’s why I’m assuming it’s a throw out bearing.

Just FYI, sitting still in neutral foot off the clutch the TO bearing is NOT turning, but the internals of the transmission are. If it gets quiet when you push the clutch in that means the TO bearing is spinning quietly and the transmission is now NOT turning. The noise your hearing is then in the trans not the TOB sitting in neutral foot off the clutch.

Try a fluid change, MOBIL 1 Synthetic ATF is the best in the stock TR6060. And they don’t like to shift cold, get the trans hot before you start trying to go through the gears quick or they will feel crunchy, the carbon fiber synchros are picky about fluid type and temp.

If you can’t get into reverse gear with the car rolling forward 1-2 mph the clutch isn’t releasing all the way, most likely cause of that is distorted surfaces on the flywheel face, center disc faces, and or the pressure plate disc face. This comes from trying to slip the clutch a bit too long during launches or from someone who slipped the clutch way to long on start offs.

My .02

 

[16GoManGoHC2]

its probably just neutral gear rattle. Most twin disk cars I have owned have had it to some extent

Clutch is out when he’s hearing this noise, discs are clamped then, there’s nothing to rattle when clamped.

 

[AeroF16]

Thanks for the replies. The noise is inaudible from inside the cabin now that I installed that rubber piece around the shifter correctly.

I did notice that it shifts quite a bit nicer when it’s warm. I have been driving it on relatively short trips lately in sub 30 deg weather but took my Son to my parents house the other day, which was a 2 hour drive. Once we got into town, it was shifting nicely the entire time. Got up in the morning to go to breakfast in single digit weather and it was really notchy again.

I will do a fluid change and not worry about it, sounds like that is just how this trans is.

 

[16GoManGoHC2]

also had it in my hellcat, and corvette with the twin disk

Nothing to due with twin disc verse single disk clutch out, it’s gear noise agree rattling around in the trans. The stock hellcat clutch center disc is bolted in place not suspended with flexible straps, there’s nothing on it to rattle around when released, I’ve changed a few, know them well, along with transmissions as I’ve busted my fair share of them too.

 

[AeroF16]

The slight rattling noise I used to hear would go away 100% of the time if I simply pushed in the clutch pedal, without doing anything else.

The minute I released the clutch pedal, the noise would be back, while sitting at a stop light with the trans in neutral.

I haven’t pulled this trans or clutch apart but is it more than a slave cylinder actuating a fork that engages the throw out bearing?

 

[16GoManGoHC2]

TOB assembly is the green unit on front of trans. The cylinder is under the green bellows, the bearing itself is the silver color disk on the end. They get dry quick but can be relubed with a needle attachment to a grease gun. I inject them with a sticky viscus grease and never hear them again. The broken input assembly is what is turning when the clutch is out, both pieces. When ice cold the fluid is thick and the opposing gears get chattered by the thick oil trying to turn them.
Try this fluid, get 5 quarts, over fill the trans a bit so oil is coming out as your tryin to get the plug back in, it helps with slosh on launch when all the oil is thrown to the back of the trans enough stays up front to keep second and third happy, stock oil sprayer only hits first gear.

 

[BULL]

That picture of the McLeod sure is purty.

 

[AeroF16]

TOB assembly is the green unit on front of trans. The cylinder is under the green bellows, the bearing itself is the silver color disk on the end. They get dry quick but can be relubed with a needle attachment to a grease gun. I inject them with a sticky viscus grease and never hear them again. The broken input assembly is what is turning when the clutch is out, both pieces. When ice cold the fluid is thick and the opposing gears get chattered by the thick oil trying to turn them.
Try this fluid, get 5 quarts, over fill the trans a bit so oil is coming out as your tryin to get the plug back in, it helps with slosh on launch when all the oil is thrown to the back of the trans enough stays up front to keep second and third happy, stock oil sprayer only hits first gear.


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Perfect, thanks for the education. I’ll swap out the fluid this weekend

 

[Old Mopar Guy]

Prepare yourself for the tranny to piss fluid all over the crossmember. Good times! You might want to check your options as far as supporting the trans and dropping the crossmember, but I couldn’t be bothered. I believe Pettys Garage offers a trans mount but it’s for A8’s only. Love to see one that would allow us to drain directly to a pan.

 

[Old Mopar Guy]

@AeroF16 and here’s one now:

https://pettys-garage.com/p-61-pettys-garage-dodge-challenger-6-speed-trans-mount-crossmember.aspx

 

[AeroF16]

Prepare yourself for the tranny to piss fluid all over the crossmember. Good times! You might want to check your options as far as supporting the trans and dropping the crossmember, but I couldn’t be bothered. I believe Pettys Garage offers a trans mount but it’s for A8’s only. Love to see one that would allow us to drain directly to a pan.

I’ll throw it back up on the Quickjack tonight and take a look.

 

[16GoManGoHC2]

It does make a mess, one you can’t clean up easily either as it stays in the nocks and cranny’s of the mount. Put a jack stand under the trans and drop the mount, 6 bolts, 2 minutes with a impact.

 

[BULL]

I honestly don't recall it being a mess to change, but I also don't remember whether or not I dropped the cross-member, maybe I did???

 

[Old Mopar Guy]

The Petty part looks like it would make dropping the tranny fluid far less messy.

 

[AeroF16]

So I’ve been reading up on the CDV and I think I understand how it works.

My question is, does removing it improve the shifting? When people talk about the improvement in clutch engagement, I assumed they meant consistency with the pedal.

Drove it around the other day and, right out of the garage it shifted great with only 4th being a little stubborn for the first few shifts on the way to work. Leaving work, it was equally stubborn in every gear.

No grinding, just very stubborn getting into gear. If I sit at a stop with the clutch in, it was still stubborn as I was shifting through the gears. I could hear a slight noise when shifting into 2nd while stopped.

The inconsistency is driving me crazy! Now I’m convinced I need to bleed the clutch. Read through the service manual and it just says to slowly depress the pedal, up to 200 times, while keeping an eye on the fluid in the brake reservoir. That doesn’t sound promising to me.

Thinking about removing the CDV while I’m doing the fluid. The manual says to do the fluid at 48 months, I can guarantee that hasn’t been done. Also going to do the diff fluid while I’m under there.

 

[AeroF16]

Sounds like Barton’s can exacerbate the problem as well, considering putting the stock shifter back in just to see.

 

[thetalonguy]

There was no change in shifting for me with the CDV. It was purely clutch engagement for me. I’ve had zero issues in shifting with my stock shifter assembly

Apparently, it’s a self bleeding system, which rids the air bubbles in the line after pressing the pedal multiple times. With the CDV, I had the clutch line disconnected and dripping for awhile while I removed delay valves. I pumped the pedal maybe 30 or so times after reconnecting and had zero issues. There was no noticeable amount of fluid lost from the cylinder

Haven’t done it yet, but where’s the bleed valve for changing out fluid?

 

[AeroF16]

Haven’t done it yet, but where’s the bleed valve for changing out fluid?

No idea, haven’t looked yet. The service manual doesn’t even talk about it.

The slave cylinder is internal to the bell housing, I’d assume there’s no way to access it without pulling the tranny.

Not sure what the rest of the line looks like between the master and the slave but I imagine there is a way to do it if you got creative.

 

[1971demon]

No idea, haven’t looked yet. The service manual doesn’t even talk about it.

The slave cylinder is internal to the bell housing, I’d assume there’s no way to access it without pulling the tranny.

Not sure what the rest of the line looks like between the master and the slave but I imagine there is a way to do it if you got creative.

So I’ve been reading up on the CDV and I think I understand how it works.

My question is, does removing it improve the shifting? When people talk about the improvement in clutch engagement, I assumed they meant consistency with the pedal.

Drove it around the other day and, right out of the garage it shifted great with only 4th being a little stubborn for the first few shifts on the way to work. Leaving work, it was equally stubborn in every gear.

No grinding, just very stubborn getting into gear. If I sit at a stop with the clutch in, it was still stubborn as I was shifting through the gears. I could hear a slight noise when shifting into 2nd while stopped.

The inconsistency is driving me crazy! Now I’m convinced I need to bleed the clutch. Read through the service manual and it just says to slowly depress the pedal, up to 200 times, while keeping an eye on the fluid in the brake reservoir. That doesn’t sound promising to me.

Thinking about removing the CDV while I’m doing the fluid. The manual says to do the fluid at 48 months, I can guarantee that hasn’t been done. Also going to do the diff fluid while I’m under there.

Is it possible your just over sensitive to this particular M6

 

[AeroF16]

Is it possible your just over sensitive to this particular M6

Could be but there’s more to it I think.

Drove it to work today. Let it warm up in the garage for about 15 minutes while I ate my lunch (only go into the office in the afternoon). 30 deg outside and it shifted great the entire time haha, so random.

My guess is that it’s a combination of the temp and some old ass fluid inside the trans.

That’s the only thing that would provide such inconsistencies with shifting that I can think of, unless the clutch engagement/disengagement timing is somehow being affected by the CDV and the clutch isn’t all the way disengaged when I’m shifting (like I’m beating it to the gear by a tenth of a second or something.)

Could also be something else in the hydraulics I suppose but I’m starting with the fluid.