spartan99

Sorry the other thread's so long I can't find responses to my post in that thread. Will I get better mileage in my stock automatic 2008 JKU with the flahspak? Can you program your computer to shift at points to offer better mileage?

klutz1001

i have a six speed so the shift points were not a problem but i started to get better mileage... i ran 33's without and then with the flashpaq and it increased a mile or two... with an auto the shift points are based on gears and tires so you wont be able to program it to shift at certain points but it should still help

spartan99

So the auto shift points can't be programmed to shift at lower rpm's? Everyone with an auto knows the shifts points are lousy. For example you'll be in overdrive going slightly uphill and you have enough power, but it'll want to downshift. If it just stayed in overdrive you'll have the power and better mileage while going uphill. Stuff like that. Please only respond if you know the answer to this question. Not trying to be a jerk just trying to avoid so many responses that I can't find the answer.

cfr

I have the flashpaq. The shift points are not adjustable. If you look at the superchips website you'll see that the shift points are labeled as "superchips optimized" or something like that.

I don't pay much attention to gas mileage, but in my experience I find that it downshifts smoother and then tends to stay in the lower gear a bit longer to avoid the constant up/down/up/down shifting.

Also note that the 91 octane tune is way better than the 87 tune in terms of driveability.

JPop

Before it actually downshifts, it unlocks the converter, which should be a 10-15% increase in rpm. Then if the engine is still not making enough power it will kick down out of overdrive, another 40% increase in rpm. Being able to override this would not be advisable as the engine would simply bog down and stall. You also need to verify if it's actually downshifting

There are two solutions available, turn off overdrive so you can avoid unlocking the converter and kick down, or second have installed a gear set that will minimize your kickdowns and gear hunting.

If you can provide some more specifics on your JK, the terrain and speed you are rolling over it, then it'll be easier to find a remedy.

As for Superchips, and adjustable shift points, it will be available at some point, but for the time being they are simply optimized.

spartan99

"If you can provide some more specifics on your JK, the terrain and speed you are rolling over it, then it'll be easier to find a remedy."

60 mph (+ or -) on a smooth freeway with a slight upgrade. The trans will hold for a while in o/d and at a decent rpm like 1900 (+ or -) or so and do fine, then downshift, kicking the rpm much higher and wasting fuel. When that happens, I throttle it a little, and the trans will sometimes go back into overdrive for me (if I do it right) and hold that gear. The downshift is unnecessary because I'm not gunning it or anything and I'm driving slowly and in that gear, there's plenty of power because the upgrade isn't so steep.

So, you're saying if I turn off the overdrive, it'll stay in overdrive?


Thanks in advance.

spinlock

If you turn off OD it will not down shift out of OD, hence avoiding the annoying gear wandering.

I rarely drop out of OD at 65 MPH except on the steepest inclines with the Flashpaq and 35s + 5.13s. However, this combination provides lower final gearing than stock 3.21s and 32s.

spartan99

So, turning o/d off, keeps o/d on? I don't get the logic. Shouldn't o/d off mean you're turning it off and thus not going into that gear? Am I missing something in the logic behind turning off the overdrive in order keep overdrive on? In every other vehicle I've owned, turning overdrive off automatically put me in the next gear down. For example, if I was in o/d and pushed the button, I'd down shift because, well, I turned o/d off so the trans shifted down a gear. Is Chrysler retarded?

I want to stay in o/d. I doesn't make sense to turn it off to stay in it. No other vehilce I've owned acts this way.

spartan99

"I rarely drop out of OD at 65 MPH except on the steepest inclines with the Flashpaq and 35s + 5.13s. However, this combination provides lower final gearing than stock 3.21s and 32s."

Autos don't come with 3:21's. They come with 3:73's. I think what's happening is with o/d off, you've turned off the o/d and you're actually in 3rd gear, spinlock. Turning overdrive off to keep it on doesn't make sense. I think you have it wrong.
I think you're not getting the annoying shifting, because your Jeep no longer tries to enter o/d because you turned it off. So, I'm back to square one, hoping to be able to change my shift points.

Calypso

You are correct about the OD. SC dosen't allow you to chance shift points, per say. But, it will give you more power and you'll find that the JK will not drop down into OD as often. You asked about fuel mileage and I can say that I picked up 2-3 mpg as have most other people. If you have an auto, it's worth the $ IMO.