Manual Transmission - Issues shifting into 1st & Reverse (Compilation thread)

[OldGuyNewJeep]

Far greater than stock.

Stock flywheel 29.6lb
CFII flywheel 43.9
ACT is 44 ? so basically the same weight.

Interesting! I wonder why it feels different than the ACT. Honestly, maybe it’s the bite point. Since my ACT was grabbing so low, maybe when I was changing gears it would immediately grab and I’d get that “pull” feeling? Like, maybe it wasn’t inertia at all, but rather an abrupt engagement of the clutch. (It took effort to make shifts feel smooth, which is not the case with the Centerforce. I can practically just shift and take my foot right off the pedal with no jerkiness.)

Maybe inertia is really about being able to crawl along with no throttle and not stall? Because the CF is exactly the same as the ACT in that regard. I can also start moving in 1st with gas and then take foot off throttle with zero bucking. Is that inertia? Again, CF and ACT are the same there - stock would buck like a bronco in the same scenario.

I drive conservatively. At around 3k RPM I’ll take foot off throttle and depress clutch pedal, shift, then gently release the clutch pedal and get back on the gas. When down shifting I’ll punch the throttle to rev match.

I dunno. I literally have just one drive under my belt and haven’t driven stock in over two years. My memory of how stock felt is probably inaccurate.

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[JeepinPete]

Inertia is dependent on weight, but also where that weight is positioned. A lighter flywheel can have more inertia than a heavier flywheel if the weight is positioned further from the axis of rotation.

"Again, CF and ACT are the same there - stock would buck like a bronco in the same scenario." That is inertia. It is my biggest gripe with the stock clutch setup.

 

[mudpup]

I think the stock JK flywheel is around 35lbs before they changed it to the dual mass crap.

 

[SadRobot]

Interesting! I wonder why it feels different than the ACT. Honestly, maybe it’s the bite point. Since my ACT was grabbing so low, maybe when I was changing gears it would immediately grab and I’d get that “pull” feeling? Like, maybe it wasn’t inertia at all, but rather an abrupt engagement of the clutch. (It took effort to make shifts feel smooth, which is not the case with the Centerforce. I can practically just shift and take my foot right off the pedal with no jerkiness.)

I think the hydraulic system on these JLs slow leak over time somehow. I hadn't realized the engagement point had gotten so low over time until someone else got in and drove it and was like "what the hell this is wrong." Turns out it had bubbles in the system again.

 

[CorvZ061]

I think the hydraulic system on these JLs slow leak over time somehow. I hadn't realized the engagement point had gotten so low over time until someone else got in and drove it and was like "what the hell this is wrong." Turns out it had bubbles in the system again.

It should be a sealed system. They only way it can get air is to pull it past a seal, likely in the slave is my guess. I think the increased clamping pressure of the aftermarket clutches is just too much for the stock slave, maybe even master not sure yet, and it’s pulling in air past the rod seals in the slave.

 

[OldGuyNewJeep]

It should be a sealed system. They only way it can get air is to pull it past a seal, likely in the slave is my guess. I think the increased clamping pressure of the aftermarket clutches is just too much for the stock slave, maybe even master not sure yet, and it’s pulling in air past the rod seals in the slave.

This is the theory that led me to pulling the trigger on the CFII with hydraulic throw-out. In fairness, McLeod came out with that implementation first, but I found a whopping 2 people who bought it after scouring this forum and the internet. Both said it failed very early on and they ditched it.

I've authored posts claiming I'd never consider putting hydraulics inside the bell housing, but here we are! I've come full circle.

I trust CF more than McLeod for this application and, as you say, the leading theory is that the stock hydraulics aren't up to the task of pushing around these heavy single-disc setups. The modified JK slave option also didn't appeal to me. At least one forum member (may have been on the sister Gladiator site) had the metal nipple break off, and that solution still relies on clutch fork (wear item) and a craptastic plastic throw-out (wear item). I think completely custom master, slave/throw-out and beefier hydraulic line make most sense.

Stellantis enshitification on display. My first and last of their brand to be sure.

Let's see. So far I'm out $4,800 for two aftermarket clutches and installations. I saved $5k by not getting the automatic, so I still consider myself ahead! Plus, this forced me to find a new mechanic since mine retired a few months ago.

 

[CorvZ061]

This is the theory that led me to pulling the trigger on the CFII with hydraulic throw-out. In fairness, McLeod came out with that implementation first, but I found a whopping 2 people who bought it after scouring this forum and the internet. Both said it failed very early on and they ditched it.

I've authored posts claiming I'd never consider putting hydraulics inside the bell housing, but here we are! I've come full circle.

I trust CF more than McLeod for this application and, as you say, the leading theory is that the stock hydraulics aren't up to the task of pushing around these heavy single-disc setups. The modified JK slave option also didn't appeal to me. At least one forum member (may have been on the sister Gladiator site) had the metal nipple break off, and that solution still relies on clutch fork (wear item) and a craptastic plastic throw-out (wear item). I think completely custom master, slave/throw-out and beefier hydraulic line make most sense.

Stellantis enshitification on display. My first and last of their brand to be sure.

Let's see. So far I'm out $4,800 for two aftermarket clutches and installations. I saved $5k by not getting the automatic, so I still consider myself ahead! Plus, this forced me to find a new mechanic since mine retired a few months ago.

I’ll be looking forward to your updates. Mine is still working fine stock, for now, but I know eventually it’ll need to be replaced. In general I like McLeod a lot better than Centerforce as a company, but if the cf is better in this application then it’s better. My experience with both brands are on muscle cars, so a little different.

 

[teedublya]

This is the theory that led me to pulling the trigger on the CFII with hydraulic throw-out. In fairness, McLeod came out with that implementation first, but I found a whopping 2 people who bought it after scouring this forum and the internet. Both said it failed very early on and they ditched it.

I've authored posts claiming I'd never consider putting hydraulics inside the bell housing, but here we are! I've come full circle...

I've got the same CF and internal hydraulics option on the way and will try to get it installed in the next couple weeks. I originally went with the CF and their external slave, then to the ACT with the CF slave, now this will be the 4th clutch my 2023 has seen. I originally wasn't keen on the idea of internal hydraulics either. Fingers crossed...

 

[OldGuyNewJeep]

I've got the same CF and internal hydraulics option on the way and will try to get it installed in the next couple weeks. I originally went with the CF and their external slave, then to the ACT with the CF slave, now this will be the 4th clutch my 2023 has seen. I originally wasn't keen on the idea of internal hydraulics either. Fingers crossed...

Holy shit, now I don’t feel so badly for buying two aftermarket solutions!

I took a long, leisurely drive with my wife today. Cruised by our local beaches and beach neighborhoods. Tons of stop and go and crawling in line at stop signs.

I have to say, this setup feels like what should have come from the factory. The pedal feel is a lot different than the ACT. It is smooth and consistent through the entire range of motion. Those here with the ACT know that isn’t the case, by design, with that setup.

The pedal is lighter than the ACT, but not as light as stock. It is very easy to launch and shift with no slipping and no bucking/jerking. I’m thrilled that it bites where a clutch is supposed to bite, rather than an inch from the floor.

I won’t hate on the ACT. Before it gave me issues I loved it, and Dirk made some great videos and went the extra mile helping my shop get things right.

So, yeah, the CF is different in feel than the ACT, and overall a lot easier to drive. My wife knows I got the Jeep “fixed,” but I didn’t bore her with details about clutch swaps because it’s not her thing. That said, she drove us home and said it was much easier to drive. She likes to sit at red lights in gear with the pedal down. (A pet peeve of mine, but to each their own.) She said it was a lot more comfortable keeping it there on the floor than before I “fixed” it. She usually has me bouncing around in the passenger seat, too, but was able to keep things pretty smooth without changing her method. That’s probably down to the bite point. It’s difficult to feather when there’s just an inch to play with. (That’s what she said! Ba-da-dum.)

Looking forward to comparing notes when you get yours installed.

And, yeah, McLeod makes good stuff, but these are Wranglers not drag cars. Seems like they rushed to market and had some kinks to work out. CF has been iterating their solution since 2018, so I feel confident with what I’ve got now.

 

[m3reno]

Holy shit, now I don’t feel so badly for buying two aftermarket solutions!

I took a long, leisurely drive with my wife today. Cruised by our local beaches and beach neighborhoods. Tons of stop and go and crawling in line at stop signs.

I have to say, this setup feels like what should have come from the factory. The pedal feel is a lot different than the ACT. It is smooth and consistent through the entire range of motion. Those here with the ACT know that isn’t the case, by design, with that setup.

The pedal is lighter than the ACT, but not as light as stock. It is very easy to launch and shift with no slipping and no bucking/jerking. I’m thrilled that it bites where a clutch is supposed to bite, rather than an inch from the floor.

I won’t hate on the ACT. Before it gave me issues I loved it, and Dirk made some great videos and went the extra mile helping my shop get things right.

So, yeah, the CF is different in feel than the ACT, and overall a lot easier to drive. My wife knows I got the Jeep “fixed,” but I didn’t bore her with details about clutch swaps because it’s not her thing. That said, she drove us home and said it was much easier to drive. She likes to sit at red lights in gear with the pedal down. (A pet peeve of mine, but to each their own.) She said it was a lot more comfortable keeping it there on the floor than before I “fixed” it. She usually has me bouncing around in the passenger seat, too, but was able to keep things pretty smooth without changing her method. That’s probably down to the bite point. It’s difficult to feather when there’s just an inch to play with. (That’s what she said! Ba-da-dum.)

Looking forward to comparing notes when you get yours installed.

And, yeah, McLeod makes good stuff, but these are Wranglers not drag cars. Seems like they rushed to market and had some kinks to work out. CF has been iterating their solution since 2018, so I feel confident with what I’ve got now.

My issues (stock clutch and 19a recall) usually reappear after 10,000 miles. I'll be looking for an update on your CF.

 

[OldGuyNewJeep]

My issues (stock clutch and 19a recall) usually reappear after 10,000 miles. I'll be looking for an update on your CF.

You’ll be waiting a while! LOL. Since Covid I work from home. I think I drove 5,000 miles in the last 12 months.

10,000 is exactly when my ACT started to fail.

 

[OldGuyNewJeep]

Pictures of my ACT.

 

[JeepinPete]

In that last picture, the marks between 12 and 3 look like heat marks (assuming that isn't dirt). That would indicate the clutch wasn't releasing evenly and was dragging in that quadrant.

 

[SadRobot]

Pictures of my ACT.

Did you send those pictures to Dirk at ACT? I'm sure they'd like to see so they can have more info for R&D.

 

[OldGuyNewJeep]

In that last picture, the marks between 12 and 3 look like heat marks (assuming that isn't dirt). That would indicate the clutch wasn't releasing evenly and was dragging in that quadrant.

Yup. It was definitely dragging. Toward the end I was frequently getting stuck in reverse, and Jeep would move in first or reverse with pedal to the floor. Overnight vacuum bleed would help for a trip or two, then the symptoms would return.

There was no incorrect grease/lube on input shaft, fork, or bearing. Mechanic took pictures. No friction material dust.

I know ACT vehemently disagrees, but stock hydraulics are not up to the task of moving their heavier components.

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