Topic: Questions about fuel economy/daily driveability

[Tr00b]

Good call on the rice burner... I've been looking for a Honda CRX Si. I have done extensive work on 80's 90's Hondas and this winter did a head gasket on my little brother's 88 CRX and have a transmission, heads and parts etc piled in my garage. Not having luck finding one worth picking up though.

Is anyone a die hard Jeep commuter? Like, its the only thing you will drive? Or do you only use it when its crappy out? Or do you drive jeeps every day no matter what?

[Jeffy]

What I was going to do to improve the economy was to run synthetics in the axles, trans and transfer case. Replace the U-joints I haven't replaced yet, fix all the shyt brakes and replace the unit hubs on the front. I'm afraid to run synthetic engine oil as I have some scabbed over oil leaks on the front cover and perhaps a rear main... I never have to add a drop of oil but don't want to start.

Then replace the 31's with sensible inexpensive road tires like these:

 http://www.tirerack.com/tires/tires.jsp?tireMake=Continental&tireModel=CrossContact+LX&partnum=175TR5CCLX&vehicleSearch=false&fromCompare1=yes

And put them on some on some alloy wheels from the J-yard or Craigslist to keep the weight down, unless I can find some nice take-offs.

It doesn't really feel good to pussify the Jeep, though...

Well all of that stuff is preventive maintenance and won't really help raise the mileage.

You're already running pretty small tires and changing them won't make much of a difference unless you're running bias ply tires and or you want to save your good tires.

As said before weight is not the problem.  Case in point.  When I was commuting, I removed about 300-400lbs from my Jeep and it showed little to no difference.  I also removed the passenger mirror as well as spare to clean up the lines.  No luck.  The Jeep was a bit peppier but no real change in mileage.  I also run a hardtop, which does get a point better in mileage then a soft top.  Aerodynamics is your #1 enemy.  At 30-35mph, wind resistance becomes more of an issue then weight.  The power to overcome air resistance increases roughly with the cube of the speed.  So it quickly increases as you go faster.

Also, alloy which usually means Aluminum cast wheels, are probably not going to me much lighter unless you're buying aluminum forged wheels.  The difference isn't going to be measurable unless you're counting the money in your wallet.

[grumpygy]

Good call on the rice burner... I've been looking for a Honda CRX Si. I have done extensive work on 80's 90's Hondas and this winter did a head gasket on my little brother's 88 CRX and have a transmission, heads and parts etc piled in my garage. Not having luck finding one worth picking up though.

Is anyone a die hard Jeep commuter? Like, its the only thing you will drive? Or do you only use it when its crappy out? Or do you drive jeeps every day no matter what?

Right after I Bought my 94 I drove it every day.  But gas Prices were much better.  Even then on real good days it was motorcycle weather.

  But Right after my By-pass i had trouble getting in and out of the Jeep and it was really cold that year and I could never get warm.  So Bought my truck it gets 4-6 MPG better than the jeep and is much more comfortable.  So now the jeep is for really bad weather.

  Right now after I get back to working I'm looking at getting a VW Passat TDI that 43 MPG is real inviting.  Never thought I would buy a car on fuel Economy.  Still not buying a smart car, well maybe as a casket.

[Mozman68]

Mine's a daily driver (35's with 4.88) and I don't think I've ever gotten better than 15 mpg.

[stan98tj]

Good call on the rice burner... I've been looking for a Honda CRX Si. I have done extensive work on 80's 90's Hondas and this winter did a head gasket on my little brother's 88 CRX and have a transmission, heads and parts etc piled in my garage. Not having luck finding one worth picking up though.

Is anyone a die hard Jeep commuter? Like, its the only thing you will drive? Or do you only use it when its crappy out? Or do you drive jeeps every day no matter what?

I'm diehard on daily driving my jeep. I've been told numerous times how dumb that is given the poor mpg. I've had (at best) 19mpg once on my 31s when driving down to Charlotte, NC from CT, all highway of course and there may have been some drafting. I did a trip to baltimore on my 33s and after a pretty long stretch it came out to around 18. Basically the 33s didn't change the mpg all that much. Around town mixed with highway and and daily driving I get 14-15, and now lower than that with the new gearing. THe gearing is what hurt me the most. I refuse to get another car, mostly because I love the Jeep so much but also because I don't really want to buy a new car and have a monthly payment for it just so I can get better mpg. Now if I buy one outright used, I can allow for up to $10k and no more. For $10,000 I'm gonna be looking at some very used vehicles-and I would have to find one I'd actually be willing to drive, but in their used condition,warranty wouldn't be great and I'd end up having to dump $$ in them too...i'm already dumping $$ in the jeep so why get another car that is going to bleed me out as well..
SO, diesel swap this summer. 28-30mpg sounds like a reasonable figure with the 1.9l. I've heard of 25-28 with the 4bt. Now if you are deadset on gettting a second car and while we are on the subject of diesel, a VW with a 1.9l (Passat or Jetta) would be VERY economical. I sailed with a 2nd mate who has a 99 Jetta TDI, 240k on the clock and gets above 50mpg with it. Sucks in the snow though, he says snow tires or chains make a little difference but he just drives his truck in the snow. My fiance had an 05 Subaru wagon, very reliable, great in the winter and got around 30mpg. She traded that for a Ford Fiesta and would get mid 40-48mpg  (once we got 52mpg on a long highway ride). But that car sucked and was in the shop 3 times (less than 6 months of ownership of a brand new 2011 model with 12 original factory miles on it) and was a complete NO-GO in the snow, SO she traded it back for a 2012 Subaru Legacy and gets 30+ mpg mixed, the Impreza is cheaper, smaller, just as reliable and currently gets the highest mpg for an AWD vehicle at 36mph (if i remember correctly) and Subarus are well equipped and not terribly expensive.

So yeah, daily driving the jeep on 31s isn't great-i did that for 4 years, but it wasn't bad enough- and still isnt bad enough to make me want to get a new car. Now, if I had a commute like yours with my current 4.56 gears and 33s, and I wasnt doing my diesel swap...i think i would start strongly considering it, but my mpg are lower than yours. Like i said, if it comes to getting a 2nd car, VW with a 1.9TDI will return great numbers and Subarus as well if you need the AWD (but you have the jeep for that, right?).

[grumpygy]

Agree on the VW Passat and the TDI.  But running real close is Chevy Cruz or Malibu in the ECO model.  Need to go down and compare then and see which I really Like.

[Tr00b]

Some great replies, thanks alot!

Jeffy: Wow ok... Good point, well researched... and thanks for talking me out of it. No sense in two people trying to defy physics or make chickens lay square eggs. Truthfully, this is the real answer to the question.

Grumpygy, what kind of pickup do you have?

Stan, I think the same way, mostly because for the last 4 years I've had the Jeep, I have been pretty broke. Now that I will have extra income, I don't want to sponge up  into another vehicle right away... The fuel economy was not bad enough to truly push me towards something else... Its "ok enough" and the Jeep is "all-purpose enough" to do everything, so why change it? I bought a trailer, so it can haul rocks, hay, wood, scrap, garbage etc and have no need for a truck.
 
I really am not a diesel freak... They are always WAY more expensive to buy that gas vehicles, and are always more expensive to fix and maintain. For instance, before I got this job I'd been looking at a V10 Superduty Ford. I could get it for 5 grand cheaper than a comparable diesel truck, pull just about as much, still start up on cold morinings, etc. Diesel is a superior fuel for energy potential and I won't argue with that, but with my luck and the price of parts, I'd never see "black" on the balance sheet with a diesel vehicle, especially an older one I can afford...

[grumpygy]

2000 GMC Sierra 1500 4X4 with the 5.3.

[Tr00b]

Grumpy...Nice... I like those, and I like the 5.3. Lots of power, easy to work on.


I did a rough estimate based on $4 fuel and my 330 mile commute. I am going to figure the cost of liability insurance for a $2000 beater (approx what I can afford cash and approx the level at which a reasonably reliable vehicle can be purchased) and license to be $580 for a year. We will assume that the car and the Jeep cost the same to maintain. I HAVE to keep the Jeep, I need it for farm work/wood cutting/survival so I am not figuring for its license and insurance costs.

I've seen as low as 12 mpg in the winter, and as high as 17mpg highway in the summer so average mpg is 14.5 lets say 15mpg is what I get now.

330 miles per week fuel  (at)  $4

12mpg 27 haf 110 per week $5720 yr
13mpg 25 gal 100 per week $5200 yr
14mpg 23 haf $94 per week $4888 yr
15mpg 22 gal $88 per week $4576 yr
16mpg 21 gal $84 per week $4368 yr
17mpg 19 gal $76 per week $3952 yr
18mpg 18 gal $72 per week $3744 yr
19mpg 17 gal $68 per week $3536 yr
20mpg 16 haf $66 per week $3432 yr
22mpg 15 gal $60 per week $3120 yr
24mpg 14 gal $56 per week $2912 yr
26mpg 13 gal $52 per week $2704 yr
28mpg 12 gal $48 per week $2496 yr
30mpg 11 gal $44 per week $2288 yr
35mpg   9 haf $38 per week $1976 yr
40mpg   8 qtr $33 per week $1716 yr

So if i get a sensible 30 mpg car, as opposed to my 15mpg jeep, the car's yearly fuel savings is $2288 minus $580 for license and insurance. The savings is STILL $1708 per year (or a weekly net savings of $32.85 per week) over driving the Jeep. But, if I have to purchase the car, it will take 61 weeks before that $2000 car pays for itself and begins to be profitable.

BUT the closer I get to 20 mpg with the Jeep... The less sense a second car makes. If the Jeep started getting 20mpg after "repairs," and the beater car still only did 30 mpg, a $2000 beater car would only save 1144 a year, minus license and insurance which is $564, or a savings of $10.84 a week. It would take 184 weeks to break even in that scenario.

So, given that analysis, it may still make sense to drive the Jeep, believe it or not, as I begin splitting maintenance pennies between two vehicles one is bound to get neglected (the poor stinkin Jeep), so its likely better to focus on one...

The better the Jeep can do fuel mileage wise of course, the better.

[stan98tj]

Grumpy...Nice... I like those, and I like the 5.3. Lots of power, easy to work on.


I did a rough estimate based on $4 fuel and my 330 mile commute. I am going to figure the cost of liability insurance for a $2000 beater (approx what I can afford cash and approx the level at which a reasonably reliable vehicle can be purchased) and license to be $580 for a year. We will assume that the car and the Jeep cost the same to maintain. I HAVE to keep the Jeep, I need it for farm work/wood cutting/survival so I am not figuring for its license and insurance costs.

I've seen as low as 12 mpg in the winter, and as high as 17mpg highway in the summer so average mpg is 14.5 lets say 15mpg is what I get now.

330 miles per week fuel  (at)  $4

12mpg 27 haf 110 per week $5720 yr
13mpg 25 gal 100 per week $5200 yr
14mpg 23 haf $94 per week $4888 yr
15mpg 22 gal $88 per week $4576 yr
16mpg 21 gal $84 per week $4368 yr
17mpg 19 gal $76 per week $3952 yr
18mpg 18 gal $72 per week $3744 yr
19mpg 17 gal $68 per week $3536 yr
20mpg 16 haf $66 per week $3432 yr
22mpg 15 gal $60 per week $3120 yr
24mpg 14 gal $56 per week $2912 yr
26mpg 13 gal $52 per week $2704 yr
28mpg 12 gal $48 per week $2496 yr
30mpg 11 gal $44 per week $2288 yr
35mpg   9 haf $38 per week $1976 yr
40mpg   8 qtr $33 per week $1716 yr

So if i get a sensible 30 mpg car, as opposed to my 15mpg jeep, the car's yearly fuel savings is $2288 minus $580 for license and insurance. The savings is STILL $1708 per year (or a weekly net savings of $32.85 per week) over driving the Jeep. But, if I have to purchase the car, it will take 61 weeks before that $2000 car pays for itself and begins to be profitable.

BUT the closer I get to 20 mpg with the Jeep... The less sense a second car makes. If the Jeep started getting 20mpg after "repairs," and the beater car still only did 30 mpg, a $2000 beater car would only save 1144 a year, minus license and insurance which is $564, or a savings of $10.84 a week. It would take 184 weeks to break even in that scenario.

So, given that analysis, it may still make sense to drive the Jeep, believe it or not, as I begin splitting maintenance pennies between two vehicles one is bound to get neglected (the poor stinkin Jeep), so its likely better to focus on one...

The better the Jeep can do fuel mileage wise of course, the better.

Jetta TDI. Exccellent reliability and over 50mpg. Or Ford Fiesta, crappy reliability (but it will be under warranty if new) and looks terrible...but you'll be getting +40mpg so who cares

[sharpxmen]

I did a rough estimate based on $4 fuel and my 330 mile commute.

All those calculations are valid if that's all you're going to drive (how much extra are you going to use it aside the commute itself?),
in that case makes more sense and is probably cheaper to take the Greyhound (if you don't need the car during the week)

I have a 10 mile commute each way which i drive daily (means about 400 miles/month), but i end up with 1000 miles/month average

[Tr00b]

Stan... I can't afford a new CAR like that. If i did spend big money on a vehicle, it would have to be a 4x4 with a good towing capacity (at least 2-3000lbs) where I would trade in/replace the Heep. I looked at CRD Libertys which have a 5000lb tow rating, but they have a fairly high cost of ownership due to crappy designs in the trans and several emissions system issues. There are known fixes too but it kina scared me away. Looking again at them though because of the outrageous pricing on the TDI's. People with modded (EGR delete, Eco tune, Suncoast Torque converter) Libbys are claiming 30mpg highway.

Sharp, I don't do too much extra driving and there is no greyhound available. I am hoping that there is perhaps a carpool I can take advantage of perhaps.

Has anyone hooked a Scangauge to their Jeep? I think i have the wrong speedo gear, will that effect it?

[Jeffy]

How about a motorcycle?  60-70mpg...

[grumpygy]

How about a motorcycle?  60-70mpg...

Not many really get that good of Mileage.  Maybe a Sportster does get closer to 55Mpg.  My Heritage classic only about 40-45.  Lots of the sport bikes get really lousy Mileage.  My old 750 Katana only got 30-35 on a good day most times it was lower.

Here is a guide.

http://www.totalmotorcycle.com/MotorcycleFuelEconomyGuide/2012-MPG.htm

You will notice the High Mileage bikes are in the 250 Range.  That size of Bike you need to stay off the freeway and no long distance 50 -60 Miles and it will get very uncomfortable.

[sharpxmen]

Not many really get that good of Mileage.  Maybe a Sportster does get closer to 55Mpg.  My Heritage classic only about 40-45.  Lots of the sport bikes get really lousy Mileage.  My old 750 Katana only got 30-35 on a good day most times it was lower.

I had a Suzuki 1000 Yoshimura long time ago (pistons, rods, cams & springs, carbs and exhaust) and was getting about 25mpg
idle was about 1500rpm