Jeep GC V8 vs. V6

[MCDenny]

Not sure if the lead times have changed but I ordered mine day after Memorial Day, got it day after 4th of July. I live 50 miles from the factory but the finished vehicle sat for a week waiting for a car carrier to bring it to my dealer.

[MCDenny]

Originally Posted by Burtim

Denny,

I'm impressed with your gas mileage. I was just looking at the weights on these trailers. You say your Snoozy weighs 2850 pounds. I found a few weights for the Casita 17 and one says he weighs 2850 pounds also ready to go with grey and black tanks empty. I'm pretty sure I shouldn't go much over 3000 pounds with all the extra junk (Honda generator) and stuff I might have. I guess the V6 is still in the running, but I am giving the V8 first choice right now. I still have about 30 days before I will be buying.

I honestly doubt a few hundred pounds makes much difference in mileage. Aerodynamics are much more important. The weight only hurts when accelerating or climbing hills. Aero drag hurts all the time. I've found a couple of 40# kayaks on the roof hurts the mileage almost as much as towing. I towed a 1700# boat 5000 miles and got about the same mileage as towing the 1200# heavier Snoozy.

I used to tow with a V6 RAV4. Another poster here, Jon Vermille tows a Casita (17?) with the same car, got the same mileage I did with the Snoozy. The bullet shaped front makes it look aerodynamic but I don't think it has any less drag than any other FGRV with rounded corners.

I think either V8 or V6 will tow a Casita just fine. If you enjoy a powerful ride and don't mind spending a few extra bucks go for the V8. I have a friend with a 2012 Durango V8. He loves it and reports 22 or 23 mpg on the freeway. A 2014 with the 8speed will do a little better.

All of my prior cars could hit the EPA hwy mileage target only if I really drove carefully (slow) and never stopped concentrating on mileage. With this Jeep its easy to hit the EPA 24 mpg hwy rating on a trip and, as I noted above, just driving smoothly and staying below 65 gives 27 mpg. Many people on the jeep garage forum report similar mileage. I found the fuel economy very slowly improved with mileage. Expect your brand new Jeep to slowly get better.

[Andrew Gibbens]

Originally Posted by Mike Magee

Tim, check the tire sizes that come with the 18s and the 20s. I am not positive but I am pretty sure I read that the overall circumferences are pretty close... meaning that the 20s are lower profile tires than the 18s. This would mean that the 20s (standard ones at least) would not give extra clearance.

Plus the lower profile 20s will ride 'harsher' than higher-profile 18s. People often assume bigger must be better, on wheel size as much as engine capacity, but in many cases the smaller diameter wheels will suit them better. The main advantage of lower-profile tires is in better handling for sporty cars.

In the sizes Mike quoted, the tire width is the same, but often the bigger diameter wheels come with wider tires - these are also good for cornering grip but have a surprisingly large penalty in gas mileage. Aero drag from wheels/tires is quite significant.

[MCDenny]

Just a little mileage update. I towed the Snoozy 150 miles up I75 today driving 60-65 into a 10-15 headwind and about 10 miles of city driving. 17.1 mpg according to the trip computer.

YMMV

[Mike Magee]

Nice results! A little early in the season to head toward the Bridge... hope the snow was all cleared off the pavement at least.

[Burtim]

So, Mike, what do you think about my situation. I know you like the V8. But I sure am liking the numbers Denny is getting. This seems like a pretty decent TV with either engine. Vail pass is probably the worst spot I will face this summer. We will be going to Las Vegas for our first big trip. I can't honestly say I know we will ever face a section of road worse than that with the Casita hooked up.

Denny, you really never have had a problem with inadequate power on the V6?

[MCDenny]

Originally Posted by Mike Magee

Nice results! A little early in the season to head toward the Bridge... hope the snow was all cleared off the pavement at least.

Umm... It was I75 in Florida. We are camped tonight at Sliver Springs SP in Ocala.

[MCDenny]

Originally Posted by Burtim

Denny, you really never have had a problem with inadequate power on the V6?

Never.

We are spending the month of April in west Texas and New Mexico, should be some decent grades to climb. I'll let you know if we run into any problems.

Tim, If you haven't already, you ought to check out the jeep garage forum. More info than you could ever want about all things jeep. There is a separate section for WK2 (current model Grand Cherokee) and many threads about towing and 100s, maybe 1000s, of posts about V6 vs V8.

Don't be put off by all the complaints in the "problems" section. I believe they are a very small but vocal (I suppose I'd be pissed too if my new Jeep had problems) minority.

[Mike Magee]

Oh, I'm glad to hear that you are still in the sunshine state, Denny. Much better where you are! Wish I could be there too, preferably driving through the Keys.

Tim, I always made it through the Rockies ok with my rig. Until this past summer (when my tranny temp light came on several times, no idea what has changed) I never had a doubt that I could make it. The Jeep has that digital transmission temperature readout selectable on the EVIC, so we need never wonder or worry how it's doing; we will know.

If you choose the V6, I think the worst case scenario is that you might find yourself driving 40-45 on a long straight climb and wishing you could go as fast as the cars. Then again it might not be that slow. I never floor my gas pedal; my mindset was to take it easy and not strain anything excessively, to downshift and hold it at 4000-4200 rpm max even though I could have pushed it harder.

But besides that, a good many of the passes are too curvy to go even 45 anyway. You might be entirely satisfied. I towed the Burro through southern CO and southern UT, including the Boulder Mtn Pass on the way to Bryce Canyon and all the way up to Cedar Breaks (10,000 feet), and I was satisfied. Then I got the KZ and I towed that over Wolf Creek Pass, up the Million Dollar Highway, then north to Glacier NP... and I was ok with the engine power available. It was last summer that got to me, with the light coming on and the headwinds while climbing grades, and I was using 2nd gear where before I would have used 3rd... and I said to myself that I would surely have myself a stronger drive train before my next trip to the mountains! I don't know, maybe the HL is just getting old. I had the spark plugs changed when I got back, but it doesn't seem any different, and the mechanics didn't have any advice beyond "slow down when you see the light come on," (but I never towed over 65 mph), so who knows.

I can say this: looking at the torque graphs, it appears that my HL 3.5L only has about 205 lb-ft of torque @ 2000 rpm, whereas the Jeep's 3.6L is already cranking out about 250. Even at 3000 and 4000 rpm, the 3.6L has a bit of an edge... perhaps 15 lb-ft. That could help it do better. Add in the Casita's aero advantage of perhaps 15%, plus the extra gear choices, and the 3.6 might be all you need.

I still can't help thinking what I could do with about 300 lb-ft @2000, and about 360 lb-ft @3000 rpm, plus 50% higher HP at those speeds, from that 5.7L.

Everyone's driving pattern will be different. And there will always be variations from unit to unit among the same exact engine. I can't help thinking that Denny got one a little more economical than the average unit (after all, he's beating the EPA estimate quite handily when unhitched). Before hearing his MPG numbers, I would have predicted 14-15 mpg towing that size egg for the 3.6L. And I would be guessing about 1 mpg less, if that much, for the 5.7L. At those numbers, towing for 25,000 miles could make about a $500 difference, I suppose. But if you really can dependably get 17 mpg with the 3.6, that difference would grow to about $1400. It's nothing to sneeze at.

[Michel, Bouchard]

Hi, I had a 1996 Cherokee Country with the L6 4.0L HO as well, I towed a 13' Boler with it and a 3500lbs Bonair trailer. The Cherokee was doing really fine with Bonair and the Boler, well, she was almost flying behind the Jeep.

Now I have a 2dr Jeep Wrangler 2012 with the new V6 Pentastar 3.6L. Ok it is not a GC, it's more like a brick on 4 wheels. Even with this awful aerodynamic, I'm doing around 21mpg at 60mph and 17.2mpg at 60mph towing our 13' Boler. So I can say I'm very pleased with that setup.

But even if the new 3.6 is showing better numbers then the old 4.0L, if my memory is still good about my old Cherokee, from what I can recall, I'm under the impression that the old engine was better at pulling heavy loads (or it's the aerodynamics that are screwing my impressions).

So, in your case, if you do long rides, mountains and with your heavier trailer, I would go with the Hemi. You will trade some mpg around town, but I'm pretty sure it will do better mpg when towing since it will be working less hard.

[MCDenny]

Last mileage report: 350 miles today 75% freeway, cruise control on 65, gentle rolling hills where Trans downshifts to 6 and once in a while to 5th. 16.4 mpg

[Mike Magee]

Originally Posted by MCDenny

Last mileage report: 350 miles today 75% freeway, cruise control on 65, gentle rolling hills where Trans downshifts to 6 and once in a while to 5th. 16.4 mpg

As a point of comparison, I believe your Rav4 with 3.5L (same engine as my Highlander) was giving you 14-16 mpg with the Snoozy. So the Jeep is doing better by 1 or 2 mpg.

When I towed the Burro with the HL, I averaged 14.3 mpg on a long trip (over 2000 miles) to Utah and back, and I think I kept it around 60-62 mph. That average included some fill-ups as high as 16.5, but they were in mountain areas with lots of curves where I drove slower.

When I buy my Jeep, I think I need you to come by and lay your hands on my hood, and rub my steering wheel, for good mpg luck!

[MCDenny]

Originally Posted by Mike Magee

When I buy my Jeep, I think I need you to come by and lay your hands on my hood, and rub my steering wheel, for good mpg luck!

Mike, as they say YMMV. Kidding aside, driving style has a lot to do with mileage. Driving like an old lady (no offense to you elderly female FGRVers) helps. I also get to practice old lady driving with our other car - a 2006 Prius. It only has one mode, slow. We still get 48 mpg though with 115,000 miles on the car.

[Burtim]

The day has come. I placed my order for a 2014 JGC Limited this morning. After weighing all the evidence it came down to one question... why did we get the Casita to begin with? To enjoy lots of traveling as economically as possible keeping things light and efficient. We ordered the V6 Pentastar engine with the trailer towing package and off road "Trail Rated" Jeep package. We had a patient salesman that we felt worked with us to get the price right. This morning he let us drive the V6, V8 and Diesel. For the Casita, we ended up feeling like all three were good choices. Since the V6 gasoline engine was by far the most popular and least expensive, the choice became more clear to us. Saving a bit of money on the engine, we opted to add a sunroof as well.

In our situation, we will be traveling to a location, dropping the trailer and sight seeing for days at a time. We decided we would likely put more miles on the Jeep exploring than we actually would towing.

It will be 6-8 weeks before we have the new Jeep from the factory. I think it will look quite nice in our neck of the woods. We'll see!

[MCDenny]

Congratulations, Tim.

You are going to love your new Jeep. I agree with your engine rationalization, obviously as it's the same logic I used. I haven't regretted the V6 choice ever.

What color did you get.

PS: if you join Jeep Garage and pay the $25 to be a premium member you can get periodic info as your jeep passes through assembly and shipping. Jeep will email you updates but the Jeep Garage info is much more complete. It sort of like tracking Santa Claus as he navigates to your house

[Burtim]

Thanks. Deep Cherry Red, more or less like the one in my last post. I always loved the red ones in the advertisements and I've always had a red Cherokee anyway. Our grand kids pretty much chose the color of the exterior. My wife chose the light frost beige leather interior with black trim. I thought that might work better than the option of black with our Golden Retriever. It might also be a bit cooler in Moab in the summer time!

[Mike Magee]

Tim, I think you have made a HUGE MISTAKE... in ordering a sunroof! (Bet you didn't expect that, right?)

I'm biased... the one on our Mountaineer has leaked several times. But lots of people have sunroofs that don't leak. Hopefully you will enjoy many sunny and breezy drives, and evenings stargazing through the open top.

As for the V6... I'm sure it will get you there and back, but that other deep-cherry-red Jeep passing you will probably be mine!

[Burtim]

Mike, you really got me there. I thought you were gonna..... well, you know. Yeah, I hope it doesn't leak too. I didn't originally have it on my wish list for that reason. I can see where it will be nice to have.

If you do pass me, hopefully you are headed to the same campground as I and we can sit back and enjoy the good life for an evening or two!

Happy trails.

[Burtim]

Denny, are you using any kind of WDH or sway control device on your setup?

[MCDenny]

Originally Posted by Burtim

Denny, are you using any kind of WDH or sway control device on your setup?

No, nothing. The Snoozy has surge brakes so can't use WDH. The trailer is quite tongue heavy, 390# with a total weight of 2850# so sway has never been a problem. When a semi passes me I can feel a very (very) slight effect as it's bow wave pushes the trailer sideways but there is never any oscillation. Driving yesterday I got on the brakes pretty hard while going 50 when a traffic light changed to yellow. No sway, we just stopped.

The Jeep's relatively short overhang from the rear axle to the hitch ball helps the stability too. It has trailer anti-sway programmed into the stability control computer but I don't think it has ever kicked in.