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Unread 05-30-2007, 03:54 PM   #61
blankster
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Question regarding fuel - Is it my imagination or does the 5.7 get a bit better mileage with 89 octaine Vs 87? I also have a 2005 300C and noticed a drop in mileage when I switched to 87.

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Unread 05-30-2007, 03:55 PM   #62
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I do a lot of mountain driving, so I'm constantly deactivating overdrive, or switching into 2nd gear. I do all of this while in motion. Does switching back & forth between Drive, Overdrive, 2nd, 1st do any harm, or can I do it as much as I wish?

Also just out of curiosity would driving with overdrive off at all times make the transmission last longer. (not going to do it.....just curious)
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Unread 05-30-2007, 03:58 PM   #63
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Quote:
Originally Posted by blankster
Question regarding fuel - Is it my imagination or does the 5.7 get a bit better mileage with 89 octaine Vs 87? I also have a 2005 300C and noticed a drop in mileage when I switched to 87.
The 5.7L was optimized around mid-grade but will run fine on 87 (or 85 in high altitude). Naturally, it runs the best on the fuel it was optimized for since we can make best use of timing/spark advance. Lastly, unless you own a 6.1L SRT Hemi, premium is definitely not needed nor will you get any benefit from it - save your pennies!
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Unread 05-30-2007, 03:58 PM   #64
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Quote:
Originally Posted by MacAttack
Also just out of curiosity would driving with overdrive off at all times make the transmission last longer. (not going to do it.....just curious)
I was in the belief that this would make your tranny die faster...
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Unread 05-30-2007, 03:59 PM   #65
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Quote:
Originally Posted by shugs
How long (miles) have the WK test Jeeps lasted so far? Does the current maintance schedule for an 06 Overland seem to be right on or do I need to do more maintanance if I want to keep this Jeep for another 50,000?

Currently I'm at 29000 and have not done any maintanence besides oil changes.
Follow the maintainance schedule in your owner's manual - that's what we do during our testing. We don't discuss specifics of testing, but we have tested to the most aggressive targets ever on a Jeep.
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Unread 05-30-2007, 03:59 PM   #66
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Quote:
Originally Posted by OnionCrk
Hi, Thanks for taking time to respond to forum questions. I have an '06 GC Ltd Hemi (first Jeep) and love it.... I've got the on/off road GoodYear SRA factory option tires and would like to like to step up one size.

Not all tire companies make the 245/65 R17 size, so can I step up to 255/65 R17 or 255/70 R17 tires without creating any problems? Do I need to have the speedometer recalibrated at the dealer? Anything else to consider?

PS: Build the TrailHawk - I want one...
I was able to pull up a tire size comparison calculator at: http://www.dakota-truck.net/TIRECALC/tirecalc.html.

I used the option: Compare Tire A to Tire B which gives the following result:

- Width Increase: 0.39"
- Overall Height Increase: 0.51"
- Circumference Increase: 1.61"

You speedo is concerned with the circumference. The new tire is 1.7% bigger which from a speedo standpoint is not significant. Be aware that at any indicated speed on the speedo will be low. For example, if the speed shows 75 mph, you will really be going 76.3 mph.

As for clearance, I'm not able to say if that particular tire will clear your bodywork. The size increase doesn't seem significant, but I don't have any experience with other than factory tire sizes. I'm sure someone else on the forum may have some personal experience and can let you know if you'll have clearance issues.

Thanks for your question.
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Unread 05-30-2007, 04:00 PM   #67
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I love the idea of Jeep vehicles with a diesel. Please continue to let the higher management know the increased need for diesels across all platforms.

My question has to do with the diesel. I know this is somewhat a future model question, but any idea how long the current WK CRD will be offered? I heard just a couple of years like the KJ CRD, but if I am going to drop serious money on an engine like that I want to make sure parts and technical support are going to be available for the life of the vehicle.
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Unread 05-30-2007, 04:01 PM   #68
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Quote:
Originally Posted by joejeep15
Why was select-trac not an option on the WK line up. I found that this option had put Jeep head and shoulders above the crowd for many years in the past. QT I is a poor replacement.
The Select-Trac is a nice box and more capable than the Quadra-Trac 1, mostly because the QT 1 doesn't have low range. But it's not a fair comparison. If you liked the Select-Trac you'll love the Quadra-Trac 2. First it has always sends torque to all 4 wheels without binding up on turns. If a wheel starts to slip, the front and rear outputs are locked together automatically. And, of course it has a low range gear to give the extra power and control needed in agressive off-road situations.
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Unread 05-30-2007, 04:01 PM   #69
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Whats with the cloth seats and water stains? I saw my buddies 2006 WK when it was only a month old it the seats looked awful! Only thing that happened was some rain got in on them. Looked worse than his 6 year old car seats did.
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Unread 05-30-2007, 04:02 PM   #70
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Quote:
Originally Posted by MacAttack
I do a lot of mountain driving, so I'm constantly deactivating overdrive, or switching into 2nd gear. I do all of this while in motion. Does switching back & forth between Drive, Overdrive, 2nd, 1st do any harm, or can I do it as much as I wish?

Also just out of curiosity would driving with overdrive off at all times make the transmission last longer. (not going to do it.....just curious)
I assume you're driving a WJ. Manually shifting the transmission won't harm it, as long as you're running the engine at resonable RPM levels(ie. not reving it too high). Often times, if you're driving in hilly terrain and you find the transmission "hunting" for gears, it's better to lock out overdrive so you elliminate unecessary shifting. As far as driving with overdrive off all the time, it's not really going to do much for you other than decrease your fuel mileage.
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Unread 05-30-2007, 04:02 PM   #71
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Thanks, I've seen the after market lifts you mentioned but was told by my dealer that anything over 2.5 will void the tranny and suspension warranty. Was wonder ing why you can't get a rubicon type lift from the factory like the Wrangler has and drive off the lot with it?
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Unread 05-30-2007, 04:03 PM   #72
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Quote:
Originally Posted by JeepEngineers
The 5.7L engine has canted valves and some valvetrain noise is typical with this type of valve arrangement due to the forces applied to the valve stem by the rocker - not only do you have downward force, but some side-loading as well. Rest assured, it will not result in any issues as the engine accrues miles.

That being the case, how would one go about making their Hemi sound like most and not make a clicking noise when between 1/4 to full throttle? It sounds horrible and not a way to attract new customers when they hear a Hemi clicking loudly when pulling away from a stop light. I mean I think it is interesting that Jeep/Chrysler/Dodge will not fix this issue on the engines that make this noise and they actually say its normal. I have been in several Hemi's that do not make this noise and would just like my Hemi to sound the same but dealer said NO...
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Unread 05-30-2007, 04:04 PM   #73
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What was the purpose of the trim piece that was in the rear wheel wells front lower that was removed for '07. The reason why I asked the question is when I went from my '04 to '07 I noticed that the noise emitted from the rear wheels when driving in the rain seem louder than our '04 WJ. I was thinking of adding some undercoat spray to the wheel wells to deaden the sound a bit.
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Unread 05-30-2007, 04:04 PM   #74
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Hi,

First of all, I would like to intorduce my self, I'm Diego, a owner of a Jeep/Dodge/Chrysler dealer for Peru. I don't have a 07' GC but since I sell them I have few details/compliments about my customers that I would like to share, also ask some technical questions.

1) Drivetrain & Electrical (Specially talking about 05'-06' and some 07' WH 4.7L V8)
  • Stall , die from the nowhere engine problems. Why happens this? Even with the propper upgrade software for FCM, PCM/TCM and rest of module from the DelaerConnect, wich I have acces as well. No TSB is present at this time at the DealerConnect for this big problem. We think sometimes has to be with something inside of the transmission or either with the SKREEM module.

Here are some links you may want to check for this issue.
  • Front Suspension. Why is so soft the fromt suspension? Can't be upgraded to something bit stiffer? Every customer that bought me a WK 4.7L V8 complimnets about it. On the highways with non flat surface at all, the Jeep will give you a "float" sensation and it creates some fear in drivers.

  • Driveshaft. Not much issues over here, just couple of WK/H's had to replace from new in warranty due making noise and vibration at high speeds. Maybe Jeep engineers could check for strenght of this piece and make it more solid to prevent this issue.
  • MPG. Many customers had the previous GC WJ 4.7L V8, they say with their new WK/H's 4.7L , the MPG dropped quite a bit. I know this is a heavier plataform, but it's substancial the decrease in MPG it give us the new paltaforms vs the WJ. We have from 90, 95, 97 and 98 octane fuel over here, using any of these won't help to get more decent MPG. Most are about 10-11 MPG in cit and no tmore than 14 MPG in highway. I know this depends on traffic, driving habits/style and other couple of things but it's too low for in my opinion. Exist any upgrade?
  • Exhaust Resonator. I notied the 4.7L and 5.7L HEMi V8 engines are loud compared with the old WJ exhaust system. Sounds like a old V8 with leaky exhaust. Many customer noticed this and don't like it.

2) Comfort and Interior
  • A/C vent slots. They can't seal enought decent while the blower is activated. Previous model seal very good but WK's not. I'm not the first person pointing this, I have read in some foerums about the same. If someone want the cockpit fresh/cold but don't want the air hitting agaisnt your face or any othe part of your body, you close the a/c vent slots so the blown air slowly go can fresh the cabbin.
  • Try this... put slow blower fan speed with A/C, seat in the back seat and wait some minutes, you will freeze. Why? Because the rear vent slots can't seal enough. While the driver/copilot want A/C , the rear passengers could not want A/C. One customer told me every time he took some passengers in the back seat, he had to add a little toilet in the arms rest to block the blown air comming from the vent slot to prevent freeze of the passengers.

Seats. Why are the seats for thw WK/H's too rigid? They don't offer ennough lateral support like the previous WJ models, wither comfortable at all. Many new customer of the GC compliments about comfort for long trips. Pain in the back.

Some has troubles with the height , agaisnt the roof. The distance it's too short even with full lowered seats.

Why the copilot electrical seat doens't have anymore the option to to adjust in altitud? Just forward-backward and back reclinable ?

A reference Thread HERE

That's all for now. If I have other question I will get back here. Hope you can read all, not be a pain to asnwer all this.

Thank you in advance.

-Diego
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Unread 05-30-2007, 04:05 PM   #75
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Quote:
Originally Posted by MGrobe
I love the idea of Jeep vehicles with a diesel. Please continue to let the higher management know the increased need for diesels across all platforms.

My question has to do with the diesel. I know this is somewhat a future model question, but any idea how long the current WK CRD will be offered? I heard just a couple of years like the KJ CRD, but if I am going to drop serious money on an engine like that I want to make sure parts and technical support are going to be available for the life of the vehicle.
We are very excited to introduce the Jeep Grand Cherokee diesel to US markets. Unfortunately, we can't talk about future products. But, we can tell you that we will be able to support your technical needs. Thanks for your interest.
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