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Well finally had a chance to bring our Jeep to the dealer to have the service manager road test it and troubleshoot the transmission. It was a tech that took my wife out in it and she quickly noticed that he was shifting at above 3000 RPM between 1st and 2nd (that is where we were having issues with rough shifting) My question to all... Is that normal? cause it sure shifts better but sounds like the piston are gon'a let loose! Were used to shifting a little over 2k. Oh he says were going to get better gas mileage by shifting at a higher RPM? Any thoughts apprieciated!
 

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I am curious about the replies you are goig to get here...

My jeep isn't quite 2 weeks old and I have been experimenting with the shift points, trying to figure out where the jeep prefers to be shifted. :)

In my Vette, I shift at around 2K if I want to keep the gas mileage down, but the real power is not until you cross 3500 all the way till just this side of redline.

In the Jeep, it seems like the power band kicks in at about 2800 or so and pulls through 4K, but it doesn't seem to have any issues shifting early.

What kind of issues are you having when shifting at 2K?
 

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I'm not sure what you mean by "rough shifting" or "shifts better over 3000 rpm" I typically shift around 2500rpm for just plain ol' getting up to speed. If I need a little more pep, I'll go over 3000 to keep the rpms up to quickly go to the next gear. (Like to get up to speed to merge into highway traffic). Did the tech tell you everything was ok? What gear ratio are you running?
 

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if its shifting rough, thats not normal. When i am shifting correctly thru all gears, my 6 speed is very smooth. You should not feel as if the engine is having to rev. My first manual trans jeep took a while to get used to in terms of when to shift, but that was due to driver trial and error. My jk has never felt rough or idling high. stock gearing and stock tires/ now with 4:88 gears and 35" tires....has always performed flawlessly.
 

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Shift RPM's

The v6 in the JK likes rev's, When driving I try to keep engine RPM around 2000 or higher, let the engine spin for a shift your not going to hurt it. 6th gear for me is an Interstate only use 70 Mph or higher. Driving and watching the fuel economy meter I noticed my fuel economy goes up (I average around 20 MPG) vs driving and lugging the engine. Rpm's up better oil circulation and coolant circulation also. Remember your not driving a tractor.:D
 

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Hey Stub I have 5 grand on the speedo now and it took about 1500 to get the shifting lined out. Mine is extremely smooth now, but my wife used to complain at first. I learned how to drive it better, I think that may be the issue. I shift at or below 2500 RPM for better mileage, no so much rev, etc.. I really do not think that it is a dealership issue. By the way, how is your Jeep? You finally gotten straightened out?
 

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Hey Stub I have 5 grand on the speedo now and it took about 1500 to get the shifting lined out. Mine is extremely smooth now, but my wife used to complain at first. I learned how to drive it better, I think that may be the issue. I shift at or below 2500 RPM for better mileage, no so much rev, etc.. I really do not think that it is a dealership issue. By the way, how is your Jeep? You finally gotten straightened out?
dcj090- Yep it is up and running better than ever. no frame damage and lots of upgrades along with the repairs (rear track bar brkt, 4:88 gears, pro-cal, poly stabilizer, poly draglink, etc). Thanks for asking.

I still feel that although there is a period of break in, and that the engine needs to rev a little as to keep it from stalling, that the symptoms described (rough shifting and feeling like the pistons are gonna let loose) is not normal. If the service tech sees no issues w/ it then maybe it is driver error.
 

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This engine really does better with a few more RPMs. My brother-in-law was driving his 2 door rubicon like it had the old 4.0L I-6 engine, shifting at low rpms. I get mine up past 3000 rpm pretty regularly. He coudln't believe how much better mine handled when he rode with me even though it is a heavier 4dr with a lift, bumpers, and winch. We both have the same tires and gears, but my shift point was higher.

Also, you only get better mileage from low rpms if you aren't having to mash the gas to maintain speed. You'd do a lot better running 1/4 throttle at 2500 rpm vs wide open at 2000 rpm.

Keep in mind, peak torque is at 4000 rpm and peak horsepower is at 5000. Don't run it up there all the time, but the tach goes up there for a reason.

Bryan.
 
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