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Weak Throttle Response on Manual Transmission Models?

grimmjeeper

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I hate to swap a perfectly functioning clutch but as soon as it starts to slip in the slightest a centerforce is going in.
If they are still using the junk throwout bearing they were using in the JK, that'll probably be what prompts you to take it apart first. And the "as long as you're in there" argument is sold for upgrading the clutch.
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Rodeoflyer

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If they are still using the junk throwout bearing they were using in the JK, that'll probably be what prompts you to take it apart first. And the "as long as you're in there" argument is sold for upgrading the clutch.
Funny you should mention that as I have a bit of rattle with the clutch released that I think is the throwout bearing. Something will eventually fail then it's all getting tossed.
 

8flat

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As everyone has mentioned, stock configuration it's quite gutless at low rpm. The motor likes to spin up and I find gets best gas mileage in the 2500-4000 rpm range.

However, you can drastically change the FEEL of this engine with a Centerforce clutch and flywheel. Your engine doesn't make any more power, but it feels like a tractor at low rpm instead of gutless. Why? The heavy flywheel stores energy, and when you let out the clutch, you release that energy (torque) instead of depending on throttle input to creat the torque. Even on 37s I can idle right up steep inclines, fwd or reverse. I can leave at a light with virtually no throttle input and can row through the gears at lower rpms.

If I did a before and after 0-60 test, it's probably slower now then before, but it FEELS so much better in normal usage.
Dude this is sweet, thanks for posting this, ever since mine rolled off the truck I've been wondering how a heavier flywheel would help this V6's horrid off-idle torque. I might try this. Did they have different options for flywheel weights, and if so which weight did you buy?
 

8flat

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Sound less like a “car engine” problem, and more a “you’re trying to drive a Jeep like it was a car” problem.
You may have missed my post about getting this turd stuck in snow? 4LO way too low to get any tire speed (required in 30" of snow), and it doesn't have enough torque to spin the tires in 4HI, especially reverse.
Any more great input?
 

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OldGuyNewJeep

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You may have missed my post about getting this turd stuck in snow? 4LO way too low to get any tire speed (required in 30" of snow), and it doesn't have enough torque to spin the tires in 4HI, especially reverse.
Any more great input?
What does any of that have to do with what you posted, which was “I'm cruising along in 6th gear, 75mph, go to pass someone and shift down straight to THIRD GEAR.”

I stand by my comment… dropping to third to pass at > 75MPH is not something I would ever do in a Jeep. You do you, though. Sorry you think your Jeep is a turd.
 

8flat

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What does any of that have to do with what you posted, which was “I'm cruising along in 6th gear, 75mph, go to pass someone and shift down straight to THIRD GEAR.”

I stand by my comment… dropping to third to pass at > 75MPH is not something I would ever do in a Jeep. You do you, though. Sorry you think your Jeep is a turd.
You suggested my problem is I am trying to drive the jeep like a car, so I pointed out a situation I had just mentioned that is most certainly not an issue of "driving it like a car".

I don't know how anyone can not admit this high-strung car engine is a bad choice for an off-road vehicle. It's literally built just the opposite of what we need in a jeep. My story of shifting to 3rd was to highlight this.
 

Toycrusher

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You suggested my problem is I am trying to drive the jeep like a car, so I pointed out a situation I had just mentioned that is most certainly not an issue of "driving it like a car".

I don't know how anyone can not admit this high-strung car engine is a bad choice for an off-road vehicle. It's literally built just the opposite of what we need in a jeep. My story of shifting to 3rd was to highlight this.
There's only one flywheel available. It probably drops horsepower a little as some energy is being used to accelerate the flywheel and maintain it in motion. It also makes the rev hang a little worse as you have more momentum spinning very fast, but it absolutely transforms the FEEL of the motor into being a truck motor. You can give it just a little gas and chug away from a stop while towing, or backing a trailer up a driveway.
 

omnitonic

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One thing I've been having trouble getting used to is that the engine fast idles at 1500 rpm for a long time. I didn't read that part of the owner's manual, but every modern fuel injected vehicle I've driven in the last 20+ years has said to just start it and go. If you start this and go, it will idle right off the line, idle to the end of my street, and when I push the clutch pedal in, the rpms go even higher for a couple seconds before it settles down.

I'm not sure if this is new, or just something I only started noticing after I got more relaxed about everything in the new ride, and freed up attention to notice this quirk.

I agree it's gutless below 2000, and I have to work harder than I want to keep it in the power band. I find myself driving it like a truck a lot of the time. In an 18-wheeler, you hit a hill hard, and just accept as a fact of life that you're going to lug up. I'm used to that, and I sort of fall into it naturally, but then I remember I'm in a Jeep and I can go. Downshift. Downshift. It's still not really going. Downshift. There it goes!

One of these days, I'm pretty sure I'm no longer going to be able to talk myself out of regearing this thing. I hate the idea of killing my excellent 22 mpg, but it sure would go better in hill country. It would crawl better off-road too. I haven't run into the snow spin problem yet, but it definitely doesn't have enough torque to spin the wheels in reverse in 4 hi. I can barely even get it moving unless I just rev the complete shit out of it, and ride the clutch.

I REALLY like this transmission. I just wish I could edit the gear ratios.

I guess technically I COULD edit the gear ratios, if I wanted to spend a whollllle lot of money on a bigger mill that could accept a bigger dividing head with compound gears, and all that jazz, so I could just make the gears I want like a boss. But let's face it, I'm never going to do that.

I wouldn't be above slapping my old T-18 in this thing if I could. It shifts like shit by comparison, but man are the ratios better.
 

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You may have missed my post about getting this turd stuck in snow? 4LO way too low to get any tire speed (required in 30" of snow), and it doesn't have enough torque to spin the tires in 4HI, especially reverse.
Any more great input?
One of these days, I'm pretty sure I'm no longer going to be able to talk myself out of regearing this thing. I hate the idea of killing my excellent 22 mpg, but it sure would go better in hill country. It would crawl better off-road too. I haven't run into the snow spin problem yet, but it definitely doesn't have enough torque to spin the wheels in reverse in 4 hi. I can barely even get it moving unless I just rev the complete shit out of it, and ride the clutch.

I REALLY like this transmission. I just wish I could edit the gear ratios.

I guess technically I COULD edit the gear ratios, if I wanted to spend a whollllle lot of money on a bigger mill that could accept a bigger dividing head with compound gears, and all that jazz, so I could just make the gears I want like a boss. But let's face it, I'm never going to do that.

I wouldn't be above slapping my old T-18 in this thing if I could. It shifts like shit by comparison, but man are the ratios better.
LOL, you two have brought me full circle! My CJ-7 has 43's, 5.86 gears and a T-18a. It crawls pretty good. But I found the trusty old 304 V-8 just didn't have enough beans. 2nd gear 4lo it could spin the tires but that didn't clear the mud. Third gear it would just bog down. So, I'm in the process of building a new engine in the 450HP, 500 ft-lb range. My point is that this problem is not unique to JL's. All 4x4's struggle with the balance of tire size, gearing and power band.
 

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AZ Hella

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I do not know sand, but that sounds way to high on the psi. For low speeds I would try 4lo first. Try 12/14/16psi next time.

"If you are badly bogged – or you have found some incredibly soft powdery sand – lower your tyre pressure until you get traction. I’d go as low as 8psi without beadlocks, or even down to 5psi with beadlocks (devices that ‘lock’ the tyre’s bead onto the rim). It’s important to note that whenever you lower your tyre pressure, your 4X4’s handling ability will be adversely affected. Hence, any cornering needs to be done with absolute caution, not only to keep your vehicle upright, but to keep your tyres on their rims.

I’ve lost count of how many tyres I’ve seen pop off their rims from sand-spraying magazine photo shoots…

And when the ground gets firm again, don’t forget to reinflate your tyres immediately. Low pressures and high speeds are a dangerous concoction, and can lead to tyre blowouts and vehicle rollovers.

TECHNIQUE

While correct tyre pressures are great, they’re not a cure-all for sand. For that you need a good driving technique. Sand naturally saps the power of your vehicle, and without power you can lose momentum and get bogged. So, the key is to keep your momentum up, and stop only when it’s safe to do so. It’s good practice to park on downhill slopes to give your 4X4 less of a chance of bogging.'
I would add that turning the traction control off in this situation helps greatly.
 

8flat

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One thing I've been having trouble getting used to is that the engine fast idles at 1500 rpm for a long time. I didn't read that part of the owner's manual, but every modern fuel injected vehicle I've driven in the last 20+ years has said to just start it and go. If you start this and go, it will idle right off the line, idle to the end of my street, and when I push the clutch pedal in, the rpms go even higher for a couple seconds before it settles down.

I'm not sure if this is new, or just something I only started noticing after I got more relaxed about everything in the new ride, and freed up attention to notice this quirk.

I agree it's gutless below 2000, and I have to work harder than I want to keep it in the power band. I find myself driving it like a truck a lot of the time. In an 18-wheeler, you hit a hill hard, and just accept as a fact of life that you're going to lug up. I'm used to that, and I sort of fall into it naturally, but then I remember I'm in a Jeep and I can go. Downshift. Downshift. It's still not really going. Downshift. There it goes!

One of these days, I'm pretty sure I'm no longer going to be able to talk myself out of regearing this thing. I hate the idea of killing my excellent 22 mpg, but it sure would go better in hill country. It would crawl better off-road too. I haven't run into the snow spin problem yet, but it definitely doesn't have enough torque to spin the wheels in reverse in 4 hi. I can barely even get it moving unless I just rev the complete shit out of it, and ride the clutch.

I REALLY like this transmission. I just wish I could edit the gear ratios.

I guess technically I COULD edit the gear ratios, if I wanted to spend a whollllle lot of money on a bigger mill that could accept a bigger dividing head with compound gears, and all that jazz, so I could just make the gears I want like a boss. But let's face it, I'm never going to do that.

I wouldn't be above slapping my old T-18 in this thing if I could. It shifts like shit by comparison, but man are the ratios better.
Spot on. It's a great transmission, put why the hell they made reverse so damn high is mind boggling. I looked into it to see if there are lower gear options for R but didn't find anything, not surprising I guess since it's new and not used in other applications too much. If you make one you could probably sell the hell out of it, haha, I'd buy it.
 

8flat

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LOL, you two have brought me full circle! My CJ-7 has 43's, 5.86 gears and a T-18a. It crawls pretty good. But I found the trusty old 304 V-8 just didn't have enough beans. 2nd gear 4lo it could spin the tires but that didn't clear the mud. Third gear it would just bog down. So, I'm in the process of building a new engine in the 450HP, 500 ft-lb range. My point is that this problem is not unique to JL's. All 4x4's struggle with the balance of tire size, gearing and power band.
Holy shit! All the torques. You'll love that in a jeep.
Yeah this is why so many people were pretty excited about the diesel option in the wrangler, seems to make a lot of sense, it's just a little pricey like all diesels.
 

Kreepin1

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Holy shit! All the torques. You'll love that in a jeep.
Yeah this is why so many people were pretty excited about the diesel option in the wrangler, seems to make a lot of sense, it's just a little pricey like all diesels.
Thanks! But in all honesty, this is the true weakness of a manual transmission off road. While an automatic will upshift and downshift to keep the engine in it's power band, with a manual you have to pick a gear and stick with it...
 

8flat

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Thanks! But in all honesty, this is the true weakness of a manual transmission off road. While an automatic will upshift and downshift to keep the engine in it's power band, with a manual you have to pick a gear and stick with it...
True.
I don't have too much of a problem shifting, the tranny is good with it even though it's a cable shifter, in cases like blasting through deep snow. 4LO and running in gears 3-4-5-6 worked pretty well last winter, as long as I didn't come to a stop and need reverse (too low in 4LO, too high in 4HI).
A supercharger would make this a decent combo though....
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