Roll your windows up and use the a/c. People think they save gas by shutting the a/c off and rolling the windows down when all they are doing is creating a giant parachute for the air to get sucked into.
This is what I do to achieve my best mileage. 1. Accelerate slowly 2. Keep highway speed to about 62 mph 3. Use AC whenever needed 4. Use cruise whenever possible 5. Keep tires inflated to 36 psi cold My lowest mileage figure ever was 24.5 mi/gal. Currently my CRD has 8400 miles.
Give it several thousand before you see significant improvement.
What your oil level. There is a tendency for some consumption in th first several hundred miles. You may need to add about one quart after 600 - 700 miles.
Mobil 1 is a good oil, but tremendously over-hyped and over-priced. (And I firmly believe that the main reason that it is recommended - by name - in our owner's manuals is that DDC Cento (nee, VM Motori) who builds our CRDs, is 51% owned by Roger Pennske who is in bed with ExxonMobil.)
Didn't need A/C, just turned the fan on, there was plenty of cold air outside and needed the heater in the AM. Issue seems to be that I'm 6mpg behind other new owners.
I have an electrical headlight tilter fitted on mine, the control knob looks like a dashboard dimmer. Do you have this on yours? The control button is a bit hidden, just below the ignition switch.
Perhaps poor quality fuel is your problem. I've noticed that when diesel fuel smells bad (stinks) mileage is normal, the uls biodiesel high tech stuff that smells like turpentine is also good for mileage. It's the in-between mixture that doesn't quite repell you that gives problematic figures. In all cases the fuel has to be very 'oily' and you will notice it has a certain ability to stain the paint and the pistol at the pump.
Called the dealership today and the EGR Gasket is backordered and won;t be available until sometime in the next few weeks comming from Europe. Chrysler paying for my rental and the bill keeps increasing $$$$$. Now driving a 2005 Jetta TDI great gas mileage.
Wondered if anyone had any opinions on Marathon diesel fuel (or the diesel fuel at Speedway stations, which are owned by Marathon). I bought one tankful - my first - at a "Murphy USA" outlet at the local Wal-Mart and was not impressed. The stuff didn't even smell like #2 fuel! I'm hoping that Marathon and/or Speedway might be better. (Hell - the Speedway Mastercard pays a 4% rebate, and the Marathon Mastercard pays 5%!)
Soft rear suspensions are pretty common for modern SUVs. I'd say beef up the rear suspension if you plan haul people & gear around and especially for towing. I got sick of the sagging rear end on cherokee everytime I loaded up for a ski trip, so I added airsprings. Airlift and Firestone make relatively easy to install kits for around ~$200usd and they're really easy to install on coil springs.
Thank you Chugga; I do all those except speed of which I can try your 62. Obviously your lowest is higher than my highest and I need to solve the riddle. Does a software upgrade exist that would change this? (01/31/05 mfg w/no upgrades applied per dealer) Does break in provide this significant of a change in mpg?(1400 mi. total now)
I just purchased a 2005 CRD Liberty Sport last friday and my dealership told me to expect mileage of 18 to 24 mpg average until the engine breaks in. From owning past diesel engines, it can take a good 10,000 to 15,000 miles to properly break in a diesel engine. It takes a long time to seat the rings.
As far as speed, pay less attention to that and more attention to rpm. On my rig the lowest rpm I can get is about 1625 rpm(approx) and still maintain highway speeds of about 56 mph. If I drop to 55mpg the transmission downshifts and puts me up at 2000 rpm. You will just have to use the cruise control and find the "sweet spots" in your transmission to get the lowest rpm within a certain speed range. For me to get the 1625 rpm I have to go up to 60mpg and set cruise control, then back off to the 56-57mph range. For me 1800 rpm produces about 62-63mph speed. Just a few hundred rpm on a diesel makes a HUGE difference. 70mph at 2000rpm+ will easily bring you down to 22mpg consumption or lower.
I drive about 100 miles a day (90 on hiway). I average about 75mph (just to keep up with traffic). The engine turns at 2200rpm. With about 10,300 mi (and waiting for new EGR to come in) I average around 24mpg, with a range of 23.5-24.5. So, I don't know about everyone saying you need to stay at 1800rpm for good mileage. I know that I would get BETTER mileage at 1800rpm, but for me, the 75mph drive is not only shorter, it keeps the rear end of the CRD from being crushed. So, 24mpg will just have to do
This came with the truck, but I never needed to use it even when fully loaded. I guess you have to use this feature while towing. Mine always stays in the same horizontal position because I usually load one heavy co-pilot up front while spouses chat in the rear seats.
I have the euro-2003 version and my global mileage after two years is 10.3 liters/100 Km. I really tried hard to drive slower, change to smaller tires, get the K&N filter, but finally winter + K&N + medium quality fuel due to the additional anti-freeze put me in the 11.5 liters/100 Km average. When milder temperatures arrive, mileage goes back to 10 liters/100Km. All in all a budget accounting for 10.3 L will be a few pennies off. The asian trucks get the same figures according to people here. The more I drive this truck, the less comprehensive I become to other manufacturers.
I think jeep is just having issues with their site. I had the same problem this afternoon. Jeep has already committed to building an additional 3000 diesel units for '06, which brings total production run for '06 to 8000. I have also heard that this number may be bumped to 10000 units if they can get VM Motori to up it's assembly. There is no way jeep is cutting the CRD with its current sales success, especially considering they will probably offer diesel options in the Grand Cherokee and upcoming Wrangler.
The mpg display indicated 32.1 mpg average for a 50 mile segment that I drove 57 mph using cruise w/ no AC. I reset the computer as I began my mpg "test". Not sure how accurate the computer is. The calculated mpg for the tank based on gallons pumped was 25.7. I have a Limited with build date of June. Tire pressure was 32 cold and the display indicated 35/36 psi. 4 oz of Powerservice in the tank and included in the mpg computation. I'm not sure what type of real world mileage will be the max I will ever see with this CRD, however, I am excited to find out. I bet I could beat Consumer Reports 11 mpg while towing a Prius and using full time 4WD!
Dealer told me that the Trac-Lok axle was no longer available on the 06 due to incompatibility with the standard ESP program. Glad I was able to locate an 05 with Trac-Lok.
As far as speed, pay less attention to that and more attention to rpm. On my rig the lowest rpm I can get is about 1625 rpm(approx) and still maintain highway speeds of about 56 mph. If I drop to 55mpg the transmission downshifts and puts me up at 2000 rpm. You will just have to use the cruise control and find the "sweet spots" in your transmission to get the lowest rpm within a certain speed range. For me to get the 1625 rpm I have to go up to 60mpg and set cruise control, then back off to the 56-57mph range. For me 1800 rpm produces about 62-63mph speed. Just a few hundred rpm on a diesel makes a HUGE difference. 70mph at 2000rpm+ will easily bring you down to 22mpg consumption or lower.
Mileage and RPM has been discussed on this site before. It was pointed out to me that the maximum mileage should occur at the top of the Speed Vs Torque curve. I've got a curve here that says the peak of the curve is about 1800 RPMs to 2000 for the diesel Jeep. After that the slope changes and the curve goes down. I usually drive about those RPMs and get pretty good mileage.
Is 1625 RPM better or the top of the Speed Torque curve? I guess the top of the curve is where the engine is the most efficient.
I think one of the posts said this had to do with the laws of physics. Maybe George Bush had those laws repealed with the tax cut.
The 4WD when not engaged means not synchronised, but always uses all the components of the transmission. We would need to disengage the front wheels drive shafts to save on fuel. I've not noticed a significant difference in mileage with the full time 4WD engaged.
Mileage and RPM has been discussed on this site before. It was pointed out to me that the maximum mileage should occur at the top of the Speed Vs Torque curve. I've got a curve here that says the peak of the curve is about 1800 RPMs to 2000 for the diesel Jeep. After that the slope changes and the curve goes down. I usually drive about those RPMs and get pretty good mileage.
Is 1625 RPM better or the top of the Speed Torque curve? I guess the top of the curve is where the engine is the most efficient
Mileage really has NOTHING to do with the torque curve. It only is a function of speed and RPM. The higher the speed at the lower the RPM (or throttle opening), the better mileage you will get.
The maximum Torque curve RPM is determined a WIDE OPEN THROTTLE. Unless you are cruising down the road at WOT, that to graph has zero to do with your mileage. The "Laws of Physics" guy had zero idea what he was talking about.
I like your results! 24mpg is good for this diesel at 75mph. I agree it is very hard to stick around 56-57mph, but if you can, and after the engine breaks in, you will see mileage in the 31-37mpg range as is being reported on many other Jeep web sites. I just want everyone to be aware of the fact that a small but consistent change in rpm on a diesel (a magnitude of 2 or 3 hundred) can make a HUGE difference in mileage after the engine has broken in for 10k or 15k miles.
A bunch of my work requires me to drive on state roads where the speed limit is only 50 to 55mph, so I'm looking forward to testing this out.
As a side note, I just got 24mpg on my very first tank of diesel, not too bad for city driving and heavy acceleration to get the engine broken in... I did keep at least 50% of that driving at 1800rpm or less, but the other 50% was well above the 1800rpm zone.
Ungn is closer to the answer. The engine has a point of maximum efficiency which is usually near the torque curve peak. However, the engine is only at maximal efficiency when fully loaded. In other words, if the engine has 300 lb/ft of torque and the torque peak is at 1800 rpms, maximal efficiency would be operating at 1800 rpms with a load equivalent to max-torque. (I know, we're not computing loads in torque, but work with me).
At lower loads, the best efficiency may be at a different speed. For example, with no load, the lowest sustainable idle is most efficient. In theory, with no load, efficiency is 0, as no work is being done. With a minimal load, the most efficient speed would probably be pretty low.
What all of this fails to account for is gearing. Gearing reduces or multiplies the effective load on the engine depending on how the vehicle is geared. At highway speeds, in 5th gear, our CRDs are operating through an overdrive transmission, through a 1:1 transfer case, to a 3.73:1 rear axle ratio, for a final drive ratio probably around 3.2:1 or so. In other words, it takes 3.2 revolutions of the engine (through the tranny, t-case and driveshaft) to turn the wheels one complete revolution. So the load on the engine is effectively reduced to 1/3 of actual load, but RPMs required to move at a given speed are increased by a factor of 3.
So maximum efficiency when an engine is not running on a engine stand must take into account the load on the engine as affected by all gearing of the vehicle. For 99% of passenger car operational hours, maximum efficiency is somewhere below the torque peak, as they are not operating at full load. (The correlation isn't quite that clean, but it generally works out that way). So most cars are geared to be slightly below their torque peak in top gear at around 60-65 mph. For semi-trucks and larger vehicles, they are geared to be at the torque peak when operating, as they operate at or near peak load much more frequently. For off-highway vehicles (tractors, bulldozers, etc.), they are geared and engineered to operate slightly faster than the peak torque RPM, to allow the engine to actually 'build extra torque' as extra load is applied and as RPM drops slightly. This is what we refer to as torque bulge.
Hope I'm not too far afield here, but it's an interesting discussion.
The BEST mileage is when you are being given the finger by speeders passing you by and you are habitually late to work; which is welcomed by your boss, because you're too stoned on coffee to be helpful once you get there. OR Best mileage is the point of inflection on the torque curve, before maxima, after minima; determined empirically from uploading 43.3 trillion data points to a Cray supercomputer running the Hogue Model, w/ number of "The Fingers" subroutine disabled, through an Excel macro. OR The best mileage is on siphoned diesel, or that stolen in a "gas-n-go".
Can someone recommend a better tire for my CRD than these worthless Goodyear Wrangler ST tires? I need something with a little grip - I looked on Goddyear's web site and the Wrangler ST is mainly a highway tire - great if all you do is drive the freeway - I need to navigate muddy farm fields -
On my Montero I ran Cooper Discoverer Radial STT's (LT) for nearly 100,000 miles. Wore tread down on the second set about half way. Found them very acceptable for dry pavement, although they sing a little with a moderately aggressive design. They always took care of me in mud and snow (usually, I gave the finger). Zero tire problems. I'm very inclined to mount them on a new set of rims for Libby.
I like Pirelli and am getting to like Bridgestone. Pirelli has a tire called the Scorpion AT. It is fairly quiet on dry pavement, with outstanding grip on wet or dry pavement. Work very well in snowy conditions.
Bridgestone has a tire called the REVO. Have never used but I have spoken to a bunch of people who have them on their SUV. They are exceedingly pleased with them.
I would avoid Michelin. They are overpriced and after about 1/3 of the tread is worn, they start getting very allergic to water.
I have heard some positive things about Cooper tires.
Driving a gas engine, you set the throttle yourself to seek the optimal condition. With the diesel engine you ask for a 'maximum speed' obtainable from the pedal position. In fact you never know how much effort the engine is producing when you have reached the condition you requested (pedal position). You would have to continuously seek for acceleration to evaluate the effort on the engine. Just try driving from standstill several times with different pedal positions and not moving the foot once you started. This is a simple way to feel how the CRD performs.
Having the ability to disengage the front hub system is something I would be very interested in. So far I have been unable to locate any aftermarket systems. Turning the front drive shafts and ring and pinion is a unnessary waste of fuel economy and performance. If any one has info on doing this to a crd, I am looking?
I just bought an '06 Liberty CRD... still less than 800 miles on it. Running with 5% biodiesel, I got 25mpg over a long road trip. Pretty encouraging given the engine is nowhere close to being broken in. The '06 models also have the electronic stability program standard - a nice added safety feature for the new model year.
I have heard a manual-locking hub kit is very available for the Liberty. Earlier models, at least. I would love to know your results after installation !
Great! I wiped out a dog that ran in front of me - couldn't stop - poor dog - but now I have a cracked front bumper! Anyone know if that plastic that they use is repairable? Thought I heard somewhere that body shops had some type of "glue" to repair plastic bumpers. I don't want to turn it in to insurance if I don't have to - another thing - the brakes on the CRD work great - locked the little bugger right up - poor dog -
You got an '06? The Jeep site doesn't even list them yet. None of the local dealers list them (CRD's) yet, although a few have '06 gassers listed. In fact the Jeep site doesn't even list the '06 gasser. Wow, you got an '06!
If we compare a fuel injected diesel and a fuel injected gasser, other than differences in compression ratios and the timing of fuel being injected (and spray patterns, duration of spray, etc.), the primary difference is only that the gasser has a throttle body regulating the amount of air going into the engine and the diesel doesn't. Assuming that the computer doesn't change the amount of fuel being introduced into the engine when the throttle is in a steady position (which isn't a fair assumption, as the computer will vary the amount of fuel being injected based on load, engine temp, transmission condition (shifting/not, gear presently engaged, torque converter locked, etc.)), with either a diesel or gasser, holding the throttle steady would introduce a certain amoutn of fuel into the engine and produce a certain amount of power that would remain constant. In the diesel, it would be a function of the amount of fuel introduced and the efficiency of the engine as an air pump. In the gasser, it would be a function of the amount of fuel introduced, the amount of air permitted to pass the throttle body, and the efficiency of the engine as an air pump. Of course, adding forced induction, etc., can change all of that.
In either case, though, the effect of throttle is the same: it produces a certain amount of power. Reduce throttle, reduce power, hold or reduce speed. Increase throttle, increase power, gain speed. That's oversimplified, as it doesn't take into account grade, rolling resistance, drag, etc. But the basic premise is the same for gassers or diesels.
Might I suggest Bf Goodrich All terrain T/A KO . I 've had good results from these grippy tires. A bit pricy<$135 US.>20 bucks difference compared to most tires ,but worth it in my book. Lots of rubber,compared to others. But if you do alot of mud bogging in the fields and backroads ,you may find the mudterrains to your liking for maximum traction . I know you are not partial to Michelins LTX M/S but I also had very good results with these as well. <$110 US.> Check out the reviews if you like,they are both top rated. www.1010tires.com/suv tire reviews www.consumersearch.com/suv tires
I am also looking at tires to replace the OEM. The ST tires are terrible, at best. All the dealers I spoke with said that they should never have been put on a jeep.
The "best" tire I have found, so far are the Michelin XLT, or Crosstrainer. They are expensive, $ 150. Sams Club, BJ, CostCO all sell a variant of the tire at about $ 110. According to the Michelin website, the variants and the originals are essentially the same.
Cooper has a SUV tire for about $ 60, but I can't find much info on it. One dealer recommended Yokohama Geolander, but its the OEM tire on my son's Forester and I can't believe that it would be good on the jeep. I won't put Bridgestone Firestone on my car due to the fact that twice (once in the late 70s and about 5 years ago) they produced tires which were defective and lied about it. That is just my feeling, but alot of people do recommend the Revo. One alternative may be the BFG Longtrail which I had on my Xterra and got good service from.
All the dealers have recommended going up one size to 235 to get a "squarer" footprint, for whatever reason.
I have about 10,500 mi on my CRD and can spin the OEM tires from a dead stop. In addition, they squeal on curves when there is little force being applied. I will replace before the snow, but have not made a final decision as yet
Hi! Acording to posts in the L.O.S.T. KJ forum (tires) The 245 70 16's will fit the stock Libby with no modifications or rubbing. Mine are on order and will be installed next week. The Bridgestone REVO is their highest rated AT tire and is now selling for $118 each less the $75 rebate on a set of 4. I will let you know how I make out! Good luck! LK
With regards to some of the problems I read are there any regrets as an owner? Would you all buy one of these again? What are your experiences with regards to changing your own oil? Any problems with goofy filter placement and drain plug access? Being told I can get an 05 Sport with the CRD for employee plan price of $23,652. I am concerned with the EGR issues that many of the 2005 owners have experienced. Should I wait for the 2006? Should I have them replace the EGR before even taking it from dealer stock? Any suggestions would be much appreciated.
Hi! I paid $23200 in july for a fully equipt Sport. The 05 is last years model and you should be able to find a much better price. I would hold out for $22000.
I had posted earlier on our 06, and they have evidently upgraded things on the transmission as we shift into 5th at 53 mph and hold at that speed which is nice. I reported good mileage on the delivery trip, but on the same tank running around here to and from our work site, the mileage has gone way down. I fail to see how the computer figures things. Either it projects the outcome based on present driving or analogs what has ocurred. A long ways yet to break in. However we love the car. BR
Comments
tidester, host
1. Accelerate slowly
2. Keep highway speed to about 62 mph
3. Use AC whenever needed
4. Use cruise whenever possible
5. Keep tires inflated to 36 psi cold
My lowest mileage figure ever was 24.5 mi/gal. Currently my CRD has 8400 miles.
What your oil level. There is a tendency for some consumption in th first several hundred miles. You may need to add about one quart after 600 - 700 miles.
2nd Choice: Ursa TDX Premium Synthetic 5W-40.
Mobil 1 is a good oil, but tremendously over-hyped and over-priced. (And I firmly believe that the main reason that it is recommended - by name - in our owner's manuals is that DDC Cento (nee, VM Motori) who builds our CRDs, is 51% owned by Roger Pennske who is in bed with ExxonMobil.)
As far as speed, pay less attention to that and more attention to rpm. On my rig the lowest rpm I can get is about 1625 rpm(approx) and still maintain highway speeds of about 56 mph. If I drop to 55mpg the transmission downshifts and puts me up at 2000 rpm. You will just have to use the cruise control and find the "sweet spots" in your transmission to get the lowest rpm within a certain speed range. For me to get the 1625 rpm I have to go up to 60mpg and set cruise control, then back off to the 56-57mph range. For me 1800 rpm produces about 62-63mph speed. Just a few hundred rpm on a diesel makes a HUGE difference. 70mph at 2000rpm+ will easily bring you down to 22mpg consumption or lower.
This time the diesel engine is no longer listed as a option...
Yesterday it was there and I printed it out... today it is not...
Maybe Jeep dropped the diesel engine... anyone know??
Not sure how accurate the computer is. The calculated mpg for the tank based on gallons pumped was 25.7. I have a Limited with build date of June. Tire pressure was 32 cold and the display indicated 35/36 psi. 4 oz of Powerservice in the tank and included in the mpg computation.
I'm not sure what type of real world mileage will be the max I will ever see with this CRD, however, I am excited to find out. I bet I could beat Consumer Reports 11 mpg while towing a Prius and using full time 4WD!
Glad I was able to locate an 05 with Trac-Lok.
Mileage and RPM has been discussed on this site before. It was pointed out to me that the maximum mileage should occur at the top of the Speed Vs Torque curve. I've got a curve here that says the peak of the curve is about 1800 RPMs to 2000 for the diesel Jeep. After that the slope changes and the curve goes down. I usually drive about those RPMs and get pretty good mileage.
Is 1625 RPM better or the top of the Speed Torque curve? I guess the top of the curve is where the engine is the most efficient.
I think one of the posts said this had to do with the laws of physics. Maybe George Bush had those laws repealed with the tax cut.
Is 1625 RPM better or the top of the Speed Torque curve? I guess the top of the curve is where the engine is the most efficient
Mileage really has NOTHING to do with the torque curve. It only is a function of speed and RPM. The higher the speed at the lower the RPM (or throttle opening), the better mileage you will get.
The maximum Torque curve RPM is determined a WIDE OPEN THROTTLE. Unless you are cruising down the road at WOT, that to graph has zero to do with your mileage. The "Laws of Physics" guy had zero idea what he was talking about.
A bunch of my work requires me to drive on state roads where the speed limit is only 50 to 55mph, so I'm looking forward to testing this out.
As a side note, I just got 24mpg on my very first tank of diesel, not too bad for city driving and heavy acceleration to get the engine broken in... I did keep at least 50% of that driving at 1800rpm or less, but the other 50% was well above the 1800rpm zone.
At lower loads, the best efficiency may be at a different speed. For example, with no load, the lowest sustainable idle is most efficient. In theory, with no load, efficiency is 0, as no work is being done. With a minimal load, the most efficient speed would probably be pretty low.
What all of this fails to account for is gearing. Gearing reduces or multiplies the effective load on the engine depending on how the vehicle is geared. At highway speeds, in 5th gear, our CRDs are operating through an overdrive transmission, through a 1:1 transfer case, to a 3.73:1 rear axle ratio, for a final drive ratio probably around 3.2:1 or so. In other words, it takes 3.2 revolutions of the engine (through the tranny, t-case and driveshaft) to turn the wheels one complete revolution. So the load on the engine is effectively reduced to 1/3 of actual load, but RPMs required to move at a given speed are increased by a factor of 3.
So maximum efficiency when an engine is not running on a engine stand must take into account the load on the engine as affected by all gearing of the vehicle. For 99% of passenger car operational hours, maximum efficiency is somewhere below the torque peak, as they are not operating at full load. (The correlation isn't quite that clean, but it generally works out that way). So most cars are geared to be slightly below their torque peak in top gear at around 60-65 mph. For semi-trucks and larger vehicles, they are geared to be at the torque peak when operating, as they operate at or near peak load much more frequently. For off-highway vehicles (tractors, bulldozers, etc.), they are geared and engineered to operate slightly faster than the peak torque RPM, to allow the engine to actually 'build extra torque' as extra load is applied and as RPM drops slightly. This is what we refer to as torque bulge.
Hope I'm not too far afield here, but it's an interesting discussion.
The BEST mileage is when you are being given the finger by speeders passing you by and you are habitually late to work; which is welcomed by your boss, because you're too stoned on coffee to be helpful once you get there.
OR
Best mileage is the point of inflection on the torque curve, before maxima, after minima; determined empirically from uploading 43.3 trillion data points to a Cray supercomputer running the Hogue Model, w/ number of "The Fingers" subroutine disabled, through an Excel macro.
OR
The best mileage is on siphoned diesel, or that stolen in a "gas-n-go".
Owhee!
Bridgestone has a tire called the REVO. Have never used but I have spoken to a bunch of people who have them on their SUV. They are exceedingly pleased with them.
I would avoid Michelin. They are overpriced and after about 1/3 of the tread is worn, they start getting very allergic to water.
I have heard some positive things about Cooper tires.
For good pricing, go to www.tirerack.com
Good luck!
B. in Seattle
I have heard a manual-locking hub kit is very available for the Liberty. Earlier models, at least. I would love to know your results after installation !
If we compare a fuel injected diesel and a fuel injected gasser, other than differences in compression ratios and the timing of fuel being injected (and spray patterns, duration of spray, etc.), the primary difference is only that the gasser has a throttle body regulating the amount of air going into the engine and the diesel doesn't. Assuming that the computer doesn't change the amount of fuel being introduced into the engine when the throttle is in a steady position (which isn't a fair assumption, as the computer will vary the amount of fuel being injected based on load, engine temp, transmission condition (shifting/not, gear presently engaged, torque converter locked, etc.)), with either a diesel or gasser, holding the throttle steady would introduce a certain amoutn of fuel into the engine and produce a certain amount of power that would remain constant. In the diesel, it would be a function of the amount of fuel introduced and the efficiency of the engine as an air pump. In the gasser, it would be a function of the amount of fuel introduced, the amount of air permitted to pass the throttle body, and the efficiency of the engine as an air pump. Of course, adding forced induction, etc., can change all of that.
In either case, though, the effect of throttle is the same: it produces a certain amount of power. Reduce throttle, reduce power, hold or reduce speed. Increase throttle, increase power, gain speed. That's oversimplified, as it doesn't take into account grade, rolling resistance, drag, etc. But the basic premise is the same for gassers or diesels.
I 've had good results from these grippy tires. A bit pricy<$135 US.>20 bucks difference compared to most tires ,but worth it in my book.
Lots of rubber,compared to others.
But if you do alot of mud bogging in the fields and backroads ,you may find the mudterrains to your liking for maximum traction .
I know you are not partial to Michelins LTX M/S but I also had very good results with these as well. <$110 US.>
Check out the reviews if you like,they are both top rated.
www.1010tires.com/suv tire reviews
www.consumersearch.com/suv tires
Good luck ...
Speak Soon
Lightnin3
The "best" tire I have found, so far are the Michelin XLT, or Crosstrainer. They are expensive, $ 150. Sams Club, BJ, CostCO all sell a variant of the tire at about $ 110. According to the Michelin website, the variants and the originals are essentially the same.
Cooper has a SUV tire for about $ 60, but I can't find much info on it. One dealer recommended Yokohama Geolander, but its the OEM tire on my son's Forester and I can't believe that it would be good on the jeep. I won't put Bridgestone Firestone on my car due to the fact that twice (once in the late 70s and about 5 years ago) they produced tires which were defective and lied about it. That is just my feeling, but alot of people do recommend the Revo. One alternative may be the BFG Longtrail which I had on my Xterra and got good service from.
All the dealers have recommended going up one size to 235 to get a "squarer" footprint, for whatever reason.
I have about 10,500 mi on my CRD and can spin the OEM tires from a dead stop. In addition, they squeal on curves when there is little force being applied. I will replace before the snow, but have not made a final decision as yet
LK
Good luck! LK
P.S. They didn't have "employee pricing" in july.