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Weberduder 07-02-2013 09:44 AM

Transmission Gearing
 
I've done a few searches but didn't seem conclusive. My first concern is when in manual mode, gear one, I can be going down a fairly steep incline 20-30mph and there is little to no resistance (engine braking) the revs just keep climbing. Is this just a quirk of transmission? I understand the hill descent control is just for 4wd low at low speeds. Am I doing something wrong?

Then the other weirdness is when towing our travel trailer 5500# if I'm going up hill in manual mode it will downshift like its still in auto mode. Is manual mode just setting the max gear and not the exact gear?

Oddly enough if I'm towing our trailer down that same hill in my first scenario the first gear does seem to apply some engine brakes to a much more significant extent but only in 1st. Is tow/haul mode changing behavior or is it just the trailer adding some resistance. Anyone have any insight?

berk483 07-02-2013 09:18 PM

Yeah that's normal for the transmission...I was a little surprised at first that it doesn't control speed a little more.

As for selecting a gear with the shifter, yes it sets a high gear limit but will still down shift if it needs to. Around town I set it at four so I don't feel it going into and out of 5 or 6 with the slightest incline. Normally I set 5 for country roads and 6 for highway. I have the V8 and don't care for MDS so I use that system and it won't activate MDS, or so I read on here somewhere.

And finally yes it states in the owners manual that Tow/Haul will make the engine try to assist in braking. I also read in there that they do not recommend using a lower gear to slow yourself down.

jeepman917 07-07-2013 07:39 PM

Re: Transmission Gearing
 
the interesting thing with the 8 speed - is - its never really the exact same feeling for me. Ive been trying to predict what it will do based on prior events -- and it rarely reacts the same.. Additionally - I notice that the transmission is smoother when the engine is colder (at startup) for first mile or so. After driving it a while - it gets shifty and more unpredictable. When I bought the car - the dealer was telling me that the transmission learns driving style - and if more than one driver uses the car - the 'driving experience' will vary.. Well I've been driving the jeep exclusively for the past month since I purchased it -- so - I don't know what the deal is. Sport mode basically reacts randomly also for me. Still the Hemi combined with the 8 speed is no where near the shiftiness of the 6 and the 8 speed. When I test drove the 6 (4 times) - I couldn't believe how shifty (and hard) it was. This was one of the major reasons why I wanted the hemi - besides more power - and - of course paying more for gas ;)

FD12ME 07-09-2013 08:36 AM

Re: Transmission Gearing
 
Quote:

Originally Posted by jeepman917 (Post 854317)
Additionally - I notice that the transmission is smoother when the engine is colder (at startup) for first mile or so.


I had this same conclusion...it was pretty smooth and predictable until it hit about 130-140 degrees then started to be rough...this was until I hit about 6800mi, where my shifting has gotten worse. 2 to 3 when cold is like I'm getting rear ended...needless to say, it's in the shop and I'm awaiting the old "nothing wrong, nothing to see here, take your car and go away, maybe they'll be a software update before you sell it in 4 years"


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