Well... If you want a cushy car-like ride... Why did you buy a Jeep?

Seriously, I did notice a tougher ride when I inflated the BFG tires to their max of 80psi, but I think I've found a fair compromise level at 60 psi. This isn't a lightweight vehicle, and P-rated (Passenger CAR) tires are too soft - You might be getting a car-like ride, but you are using the tire to more than 80% of it's capacity just with the raw vehicle. Personally, I like a bit more of a safety factor.

As for the city mileage, I have been leaving the EVIC alone for several weeks now (haven't reset it) and I also have been driving the same 8-10 miles per day of a city route. Not my usual mostly-highway runs. So, I think that the EVIC's number now is based entirely on the city driving. It reports 20.5mpg. If we adjust for the EVIC's typical 2mpg over-estimation, that says that this 3400 lb brick is getting 18.5mpg in city driving.

I don't know if that is good or bad compared with stock, I didn't have the EVIC when I had stock tires, and I only had the BadYears on there for about 2 weeks after I bought the KJ. So I personally have no baseline. BUT, compared to my OTHER Jeep (96 Grand Cherokee with V8 ) 18mpg is fantastic. 18 is about all the 96 can get on the HIGHWAY, downhill. It usually gets about 16, and 10 in the city. Admittedly, it probably needs some engine sensors however, as it has over 200k miles on the original O2 sensors and most of the other stuff.

I think that sounds a little low, why don't you try calculating it by hand for a little while and see what you get? 2mpg at 30mpg is alot different than 2mpg at 20mpg.

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"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

Color me confused: Low... as in the difference from the EVIC should be more than 2mpg from actual? Or you think I should be getting more than 18 in the city?

If the latter, I'd LOVE to be getting more than that. As it is, I practice some hypermiling techniques when driving around in the city. I kick it into neutral whenever possible, especially at lights, but coasting instead of accelerating constantly seems better to me. Especially when you have to be stopping constantly.

I calculate by tank to fill volume and miles driven.
Allowing for variances in full tank of course.
Just want to point out that my mileage by odometer is less than driven miles determined by road markers, my speed is about 5 mph low at 65mph by GPS.
So I get 20-26mpg plus odometer error.
Wish I had gone with the 225-85-16's.

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'06 Jeep Liberty Sport CRD with: GDE Hot Flash and Tranny Flash, ehm, Cummins fuel pump, 3" Magnaflow muff, Moog K3199's, Skids, 225-75-16 10 ply, OME springs, Euro T/C, Shift kit, Trans cooler w/thermal bypass, Bigboy bkt, Samco CAC, Brake controller, Trans temp gauge, Al's Upper Arms

Generally speaking, I calculate by full tanks too. But since I've been home, I haven't had enough green to fill the tank the whole way. I'm also not driving enough to WANT to be hauling around almost 200 lbs of fuel weight.

Keeping the tank below 1/4 does add to the mileage, and easily balances any added weight from the larger tires. Besides, at no time am I more than 10 miles from a diesel station (frequently no more than 2 miles) and the range of my KJ once the fill-me-now light comes on is at least 30 miles. (I've pushed it, and still don't know where the bottom is)

So I kinda have to calculate based on the EVIC's numbers, at least for now.
I can't remember the specifics of odometer-to-reality that I tested with my GPS right now. If anyone really cares about how this size changes the readings, I can check and get back to you.

I keep my tank full or at least 1/2 full or 1/2 empty, whatever, to keep the water gremlins at bay.
Had a Case backhoe, always looked for water in the fuel bowls, often found it.
If my tires were about 4% bigger that would be enough to make my speedo ok.
The rascal has plenty of lugging power and I have not done the Inmotion yet.
Just wanted to keep the tires small for towing, have not towed much at all.

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'06 Jeep Liberty Sport CRD with: GDE Hot Flash and Tranny Flash, ehm, Cummins fuel pump, 3" Magnaflow muff, Moog K3199's, Skids, 225-75-16 10 ply, OME springs, Euro T/C, Shift kit, Trans cooler w/thermal bypass, Bigboy bkt, Samco CAC, Brake controller, Trans temp gauge, Al's Upper Arms

Smaller tires for towing... Why? I've pulled 7,000 lbs with these tires, and haven't had ANY problems with needing to downshift. As a matter of fact, pulling a trailer this summer that was probably almost overweight for it's OWN tires, I still got an honest 19mpg at 70mph.

The same trailer (with only about 2900 lbs total weight) behind my V8 Grand Cherokee... The GC got a glorious 10mpg, and was running warm the entire 500 mile trip.

These little mules were BUILT for towing. Oh, and I'm sometimes convinced that the temp gauge is painted on, as I have never seen that needle move above straight up when towing. So the engine just isn't struggling at all.

Not sure if this thread will be the best, but I am trying to get advice on mods to maximize my mileage while towing. As a newbie, I have not been able to find a towing performance thread.

I know there are many factors tied to the trailer, but I am interested in CRD mods that will increase mpg. Any ideas are welcome - air intake (filters, induction systems, etc.), fuel brands/types, exhaust, computer mods, tranny/shift kits, tires/pressure, etc.

I am towing a 4000 lb trailer 90% of the time, so would not want any changes that would compromise that function (low-load tires, reduced torque, etc.). Currently, I am getting about 24 mpg un-trailered on flat freeway at 70 mph. A few towing runs have given about 16 to 17 climbing/descending over 2000 ft for about 40% of a route. I would like to think that I could get over 20 mpg towing, but am I dreaming?

Thanks for any guidance
Russ

Howdy biofuler

Welcome to LOST - basic 1st principles - you need to do something about the Crankcase ventilation - it's dumping oil into your intake - so check out the CRD Tech for EHM or Provent.
also check the Fuel head heater - to make sure you're not leaking air (although if you haven't had drivablity issues - you're probably okay)

I don't Tow - based on posts - I'd say 20 mpg depends on your trailer - Geordi's 7000 lbs - has almost no wind resistance - it's tucked in behind the Jeep (but 2000 over the towing limit) and he gets 18-19, Chrispitude and Danoid - tow huge campers - they weight less than Geordi's but have worse Aerodynamics and they get worse mileage. (someone mentioned towing a Casita - which is small and I think they were better than 20 - don't remember the exact number)
So if your 4000 lbs isn't a parachute - you can probably get to 20 - on the flat - I wouldn't expect that going up mountain passes.

you might also look at performance modules (or Inmotion tunes) - and you might also want to checkout the Suncoast TC


(found it - it was a Scamp and he gets ~22) - the thread also has photos of some of the other trailers
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?p=299306#299306

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2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

Geordi
Is your truck lifted? If not, does the BFG T/A 215/85/16 tire has an aggressive tread at all or is it strictly on road?
We live off road. Our house it at the top of a mountain in central Virginia near the Blue Ridge. All winter, spring and during the late fall the road is next to impassable. We live about two miles from a hard surface road.
I had Cooper Discoverer AT's on my '92 Cherokee before trading it for the CRD. They provided the best semi-off road performance of any tire we ever had on the little box. It had 235,000 miles when we did the trade. I attributed their performance on ice to the softer rubber. They did not last as long as Michelin's but they really held onto the ice we encounter all winter. I never used tire chains while the Cooper's were on the box. Couldn't navigate the road in the winter without chains when we used Michelin's, and the same holds true for the stock GY's on the CRD.

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2006 GC Lar 4.7L V8 Stock
2006 CRD Liberty: substitute Provent; SEGR

Wow... Zombie thread back from the dead!

Let me reply in turn here, so I don't miss anybody.

Biofueler: Welcome to Lost! The pictures in this thread are of my Jeep, with a sizable generator on the back. That pic doesn't truly show it, but that genset is just as tall and almost as wide as the KJ. So yea, it is *just* barely hiding itself from the wind.

As far as the towing ratings... Think about this please: The European versions of our CRD is the *exact same* truck, with a different variation on the license plate mounting and different language on the gauges. Their owner's manual specs out a 7,000 lb tow rating. That isn't a rounded number, the Kg number is the non-round-number. I can't recall exactly what number right now, but there it is: Our CRD is rated for 7k lbs of towing.
Now, for the USA owners manuals... A couple things to remember: Chrysler is petrified of being sued. Chrysler DID NOT MARKET this engine like they could have, and as such, probably did not do NEARLY the level of testing that the Europeans have done for their own regulatory agencies.

In the USA manuals, the CRD's tow rating is exactly the same as the V6 gasser. Are the specs of the engine the same? Hardly. The CRD produces FAR more torque than that anemic little v6. Torque gets the job done, HP is to make your *censored* seem bigger.

Now, about my towing experiences... Thus far, I have clamped 4 different bricks to the back of my CRD and dragged them around:

A Haulmark 6x12 enclosed box trailer, single axle. Both loaded and OVER-loaded. It's profile is taller and wider than the KJ, and it has an almost-flat front. That is the one that I pulled (at about 4000 lbs) and got 18mpg in the mountains by Albany.

Haulmark 7.5x20 enclosed car hauler, dual axle, almost flat front. This thing is frelling HUGE in the wind. Also, pulling it with one flat tire (that I didn't know about) probably didn't help. I have only pulled it empty, and it's dead weight is about 2600 lbs... But the surface area of the front might as well make it weigh 10 tons. It won't be pulled by my CRD again, I got it to ride behind my RV... Potentially with the CRD inside it. That one trip however, I couldn't get the CRD over 65mph without dropping out of overdrive, and only got 14mpg on FLAT roads. Worst I've had in the CRD, and I'm not doing that again.

Generator in the pictures. 6840 lbs (scaled it to know for certain) and 19mpg at 65mph with that beast on the back. So if wind isn't your problem... Weight shouldn't be either.

Lastly, a smaller generator, just like it's bigger cousin, except single axle and total weight of only about 2000 lbs or so. Pulls like it isn't even there, and it is much smaller / narrower than the big one. 20+ mpg easily. I've pulled that behind my family's HYBRID Mercury Mariners... As well as asking the hybrids to pull both my own CRD and my 97 Grand Cherokee with their tow bars. Good hybrids, for a 4-cyl hamster wheel.


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Now, about the tires:

These are my tires:

Hankdz: Check the link for complete info: http://www.bfgoodrichtires.com/specs/commercial-t-a-all-season/45.html

My experience has been that better performance on icy roads is gotten with a narrower tire that can push through the ice and find the roadway underneath. The best example of this I have is my RV, which is wearing tires with VERY similar tread patterns and performed just fine in a truckstop in NC that was a complete solid sheet of ice. I know exactly the kind of terrain you are talking about, I'm a big fan of the Skyline Drive and the national park up there. Now, for most of the year, I'm going to guess that you are dealing with the legendary Virginia clay as it's best friend... Virginia MUD.

I don't know for hill climbing in mud, but I hope you aren't trying to make your KJ climb muddy walls... But I'm a grad student in Savannah, Georgia. We have a "mud season" here twice a year, and it is much of the same stuff. I think companies actually WANT this level of slippery when they are pushing pipes underground... But it sucks to drive through.

This is mud that will suck off a fully-laced BOOT from your foot, SOCK TOO. That is the kind of glop that I drove those tires through, both pulling that 7k lb genset, and then rescuing the box truck. (film set location) The guy with the Explorer had taken his 2WD (idiot) with fat wide tires into the mud for fun, and had gotten himself stuck in a DEEP area that I wasn't even thrilled with going into to rescue him. But the narrow pizza cutters push through the squishy top layers to find more solid stuff below. Not only did I not have a problem, I pulled his Explorer out SIDEWAYS for the first 5 feet before his front end had turned enough to follow and find traction. (there wasn't much, I had to drag him almost 1/4 mile until we got back to the paved road)

Oh, and my KJ is NOT lifted at all. Stock everything, except for the tires and the SEGR / Edge Trailjammer.

Geordi
Perfect description of the mud. I've been in your part of the country and it looks the same as here. Maybe yours has a little more iron oxide for that redder color, but essentially the same.
I appreciate you taking the time to describe your use of the tires and the kinds of situations they helped you out of. Thank you.
Hank Dz

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2006 GC Lar 4.7L V8 Stock
2006 CRD Liberty: substitute Provent; SEGR

I've never been able to "push" through the ice to the road surface below. Snow....yes, but ice....no.

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2006 Sport CRD

Could the Aztecs have known, that in 2012 after a 4 year experiment, our country would cease to exist?

I just put these on my CRD size 245/70R16 today. They road force balance real nice and felt smooth and quiet on the way home. Got them at tire rack outlet business account for $122.00 each.

http://www.tirerack.com/tires/tires.jsp ... TX+A%2FT+2

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2006 Black Jeep Liberty CRD Limited
K&N, Samco Hoses, Michelin 245/70-16 LTX A/T2, Fumoto F-102, V-Force Muffler, Mopar, Hitch, Trailer Wiring, Skid Plates, Slush Mats, Rear Shelf, Predator Stage 1, Transgo, ORM & CodeReader, Facet 40109 Pump
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