Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (http://www.jeepgarage.org/forums.php)
-   Grand Cherokee - WK2 - (http://www.jeepgarage.org/f73/)
-   -   WK2=poor coaster (http://www.jeepgarage.org/f73/wk2-poor-coaster-17905.html)

Cperez 01-24-2011 10:53 PM

WK2=poor coaster
 
I have noticed that my Overland is an extremely inefficient "coaster." Even on an extended downhill run of moderate slope, it will barely pick up speed and sometimes even slows down. It's not happening to ridiculous levels, but there's a distinct sense that the engine compression/gearing or whatever you'd call it, is always there working against a good long coast. Even in neutral she's no superstar; more on that in a bit.

My last couple of new vehicles, and even the older WJ, were very good coasters. There's a rollercoaster stretch of road on my regular drive home. If I hit 50 mph at exactly a certain point, I was always able to make it almost all the way to the end of the stretch by coasting in neutral. No way in the WK2.

On that note, I thought I read somewhere long ago that it's not good to coast for extended periods in neutral because some pumps and other systems rely on the engine being in gear to operate properly (not to mention that it is illegal in many places to coast in neutral downhill, but that's for safety and not mechanical reasons). Any expert insights on any aspect of this subject? This may be one of the more obscure topics that's been discussed here but I'm curious if others have noticed this as well.

Knightrider03m 01-24-2011 11:19 PM

Re: WK2=poor coaster
 
My KK does the same thing. I'm guessing it has something to do with the fuel shut off whenever our feet is off the gas.

CrazyJ 01-24-2011 11:27 PM

Re: WK2=poor coaster
 
That kinda sucks. I was hoping for a good coaster. I've always had to pop my 4runner out of gear, which is annoying.

Does anyone have any opinions on the v6 coasting? Different rear end and tranny may make a difference.

Cperez 01-24-2011 11:34 PM

Re: WK2=poor coaster
 
More testing is definitely called for, but seat-of-the-pants feel is noticeably different than the RR which was a champion glider...and weighed 200 lbs more.

CrazyJ, I am talking primarily about coasting in neutral. I only mention in-gear coasting because it still feels like it is in gear and limiting me just barely, but more than previous vehicles I've driven.

Nbtstatic 01-24-2011 11:38 PM

Re: WK2=poor coaster
 
Quote:

Originally Posted by CrazyJ (Post 341031)
That kinda sucks. I was hoping for a good coaster. I've always had to pop my 4runner out of gear, which is annoying.

Does anyone have any opinions on the v6 coasting? Different rear end and tranny may make a difference.


I've always thought my V6 Wk2 was a good coaster. Very subjective, of course, but I was surprised when I saw this thread title.

And I agree, they are likely to be somewhat different in this category.

NB

Technosavant 01-24-2011 11:54 PM

Re: WK2=poor coaster
 
It isn't a "coast forever" vehicle like some vehicles of years past. Personally, I prefer it to slow somewhat when I let off the throttle; it makes it easier to adjust speed without using the brake.

Hogs 01-25-2011 12:43 AM

Re: WK2=poor coaster
 
I'm glad someone brought this up. After only a few days of ownership this was one not so great things that stuck out most to me about my new WK2.
I've always felt that there is a direct correlation between the amount of breaking you do and fuel mileage. Going directly from the gas pedal to the break pedal is an inefficient means of driving. So if I see a red light a 1/4 mile ahead, and traffic in front of me, I like to coast to the traffic (or the light) instead of gassing there then breaking when I get there. I hate it when people drive like that (wifey).
In my wife's corolla (auto), I can let off the gas and she'll coast forever (avg 33 mpg). In my F150 (manual), I can pop it into nuetral and it will also coast pretty far (avg 17 mpg). Apples to oranges vehicles with the WK2 of course.
But when I let off the gas in my WK2 it reminds me of my Yamaha Grizzly quad that has engine breaking, in that it immediately starts loosing lots of forward momentum, almost as if there is an engine breaking system.
I'm sure there are lots of variables involved from weight, tire size....and maybe it 'loosens' up over time...
Is it possibly a 4X4 vs 4X2 issue caused partically by the additional friction of the full time transfer case?

moosehead 01-25-2011 03:17 AM

Re: WK2=poor coaster
 
I understand CP's original post, but gotta say, when this big beast gets rollin on an extended descent, better get outta the way. In these circumstances, the WK2 handles speed really well for a brick on wheels and we're grateful for the manny downshifting abilities.

Cperez 01-25-2011 07:08 AM

Re: WK2=poor coaster
 
Glad you brought up downshifting, moosehead. I have noticed that I have to get into 2nd gear before I get any type of appreciable engine braking. During our NYE weekend trip, we had a 3+ mile descent off the mountain top and downshifting was really necessary to spare the brakes. My wife kept asking "why is the engine making that sound?" I got tired of explaining it to her and just turned up the volume on the stereo. :mad:

To those who enjoy adjusting speed without using the brake (or even the throttle)-- your resident ACC jockeys do it all the time!:thumbsup:

tkln 01-25-2011 09:24 AM

Re: WK2=poor coaster
 
Ditto for me on the coasting...I have a hill by me that I used to be able to get all the way down with no issue, now I have to pop it into neutral to get to the bottom. That being said, I too enjoyed the slowness in certain steep situations. I guess you can't have it both ways!

Cperez 01-25-2011 10:19 AM

Re: WK2=poor coaster
 
Glad to see others are experiencing this also, and I appreciate the comments that seek to turn it into a virtue. I'm not complaining but if I had my druthers, I'd prefer a better coasting vehicle. Still digging this Jeep, though.

Now on to my other question-- does anyone know of any mechanical caveats to occasionally rolling in neutral?

pwguy 01-25-2011 10:27 AM

Re: WK2=poor coaster
 
Quote:

Originally Posted by Cperez (Post 341216)
...does anyone know of any mechanical caveats to occasionally rolling in neutral?

Well there is what it says in the manual.

NOTE: Towing the vehicle, coasting, or driving for any other reason with the shift lever in NEUTRAL can result in severe transmission damage. Refer to “Recreational Towing” in “Starting and Operating” and “Towing a Disabled Vehicle” in “What To Do In Emergencies” for further information.


All times are GMT -5. The time now is 11:21 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community