Question of the rpm for manual transmission

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bio86250

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Drop the clutch every gear... it's good for it. It may not seem like it but you want it to grab hard every shift. Anything else is decreasing the life of the clutch. Also, shifting at 3500rpm is nothing for this motor, it loves to rev.
Note it, I'll give a try, thanks for sharing





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Elsinore73

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I think the JL has one of the best clutches I have ever driven, but the lack of low end torque on the 3.6 combined with the rubicon gearing means you want the revs up or it has a tendency to lug when short shifting. My previous car was an Audi A4 wagon with a 6 speed manual, that had tons of low end torque and loved to be short shifted, the JL not so much.
 

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I think the JL has one of the best clutches I have ever driven, but the lack of low end torque on the 3.6 combined with the rubicon gearing means you want the revs up or it has a tendency to lug when short shifting. My previous car was an Audi A4 wagon with a 6 speed manual, that had tons of low end torque and loved to be short shifted, the JL not so much.
Curious why you say "combined with the rubicon gearing". The rubicon has a 4:10 gear ratio which is shorter than the other models meaning it catches better and has more torque multiplication. I have 4:88 gears and 37" tires and its slightly shorter than 4:10 and 33"s, but I can definitely short shift my Jeep. If you have the right gears for your tire size it will be fine at 1.5k rpm and shouldn't really lug or anything, maybe it will ping a bit.
 

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Note it, I'll give a try, thanks for sharing
I do hope Rodeoflyer was joking about suggesting to drop the clutch in every gear. I would not recommend driving like this regularly. Sure when I'm on the drag strip with my GTO I'll drop the clutch between gear changes and smash the throttle back down to the floor, but that does create a shock in the driveline. The purpose of the clutch, besides disconnecting the engine from the drivetrain, is to ensure a smooth transition between engine speed and road speed. Dropping the clutch puts a shock load on the drivetrain components that can eventually cause them to wear and have excess play. You'll end up with a lot of clunking and slack takeup as this can affect driveshaft pinion / yoke joints, u-joints, diff gears, etc. I'd rather replace a clutch and pressure plate (which are wear items anyway) then troubleshoot a sloppy drivetrain.
 

jdubya421

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I do hope Rodeoflyer was joking about suggesting to drop the clutch in every gear. I would not recommend driving like this regularly. Sure when I'm on the drag strip with my GTO I'll drop the clutch between gear changes and smash the throttle back down to the floor, but that does create a shock in the driveline. The purpose of the clutch, besides disconnecting the engine from the drivetrain, is to ensure a smooth transition between engine speed and road speed. Dropping the clutch puts a shock load on the drivetrain components that can eventually cause them to wear and have excess play. You'll end up with a lot of clunking and slack takeup as this can affect driveshaft pinion / yoke joints, u-joints, diff gears, etc. I'd rather replace a clutch and pressure plate (which are wear items anyway) then troubleshoot a sloppy drivetrain.
Precisely. That's why it's a clutch pedal with travel and not an on-off switch.
 

Elsinore73

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Curious why you say "combined with the rubicon gearing". The rubicon has a 4:10 gear ratio which is shorter than the other models meaning it catches better and has more torque multiplication. I have 4:88 gears and 37" tires and its slightly shorter than 4:10 and 33"s, but I can definitely short shift my Jeep. If you have the right gears for your tire size it will be fine at 1.5k rpm and shouldn't really lug or anything, maybe it will ping a bit.
Your right on the rubicon gearing being better for low end. I have never driven a non-rubicon manual JL so have nothing to go against as far as another JL goes. It’s all relative and coming from a turbo Audi I’m just not used to it. Anything sub 2k rpm’s has no guts and if my up shift leaves me sub 1700 it wants to lug. Running 315’s with the stock 4:10 gears. Love it though, not complaining, just my observation. The 4.0 in my old TJ was much better down low.
 

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Wait until you start learning the feel of shifting in 4 low. I'm still getting use to that..

But for me, 1->2->3->4 is 1k difference. 4->5 is 500, and 5->6 is 250 rpm difference. I generally shift at or above 3k rpm for the first 4 gears, and gauge from there.
 

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Wait until you start learning the feel of shifting in 4 low. I'm still getting use to that..

But for me, 1->2->3->4 is 1k difference. 4->5 is 500, and 5->6 is 250 rpm difference. I generally shift at or above 3k rpm for the first 4 gears, and gauge from there.
So true! Completely different shifting in 4L, 4H, and 2. All different.
 

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So true! Completely different shifting in 4L, 4H, and 2. All different.
I feel like a complete novice for the first hour, mostly for downshifting. But you do get use to it. You'll love crawling down a hill in 1st or 2nd. Starting after a stall on a hill is super nice in 4 low.
 

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I feel like a complete novice for the first hour, mostly for downshifting. But you do get use to it. You'll love crawling down a hill in 1st or 2nd. Starting after a stall on a hill is super nice in 4 low.
Yep same! Haha. It’s sooo easy in 4 low to just crawl down. Basically set it and go.
 

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3200-3500 before going to second. atleast with the crappy 3.45 sport gears. im hoping that the 4.10s will be much better. also note that the wranglers rpm are slower to drop than a normal older manual trans vehicle. its in the system to hold the rpms up a few mil seconds to " help shifts to be smoother. but its really just a PIA
 

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Just drive the jeep and do what feels good. If the jeep shakes, you shifted too soon. Let go the clutch by feel, learn the sweet spot at different speeds. It should feel natural. If it yanks, you did it too fast. Drive it smooth. Dont shift without the clutch, people think it is cool. It isnt. Wear down the clutch, not the gears.
 

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And enjoy the stop start yelling at you at red lights where you go to shift too fast. I get beeped at often..
 

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3200-3500 before going to second. atleast with the crappy 3.45 sport gears. im hoping that the 4.10s will be much better. also note that the wranglers rpm are slower to drop than a normal older manual trans vehicle. its in the system to hold the rpms up a few mil seconds to " help shifts to be smoother. but its really just a PIA
Yeah, you need to rev up the Sport to around like 3k when shifting otherwise you will probably end up getting bogged down.

The rev hang is an emissions control "feature" and is annoying but you just have to be patient.
 

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Some other things to consider, IMO.

Turn OFF the ESS.
Turn OFF the hill assist.

IMO this leads to a more "normal" feeling clutch. This engine loves to rev and I've rev limited it a couple of times when my music is too loud and I'm not paying attention... lol.
For 1st - 4th I will almost always take it up over 3k rpms before I shift. The 3.6L does not come alive until you are above 3k.
For what it's worth I'm running 37s and 4.88 gears.
 

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