Newbies and Vets: Tips for better fuel economy!

gary9696 said:

Were your original tires already worn out? I have original Hankook tires on my 2010 Jetta TDI SportWagen that I bought new on 3 Dec 2009, the vehicle has 26,500 miles on it, and I don't think the tires are half worn yet. I have always used the maximum psi on the tire sidewall which is 44 psi, and the tires have never shown any center tire wear, it is even wear across each tire.

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Tires developed terrible road noise as they wore (Turanza's). Also traction during some icy winter weather got me thinking about when to replace them. Then I needed an alignment and that just forced my hand all together. The new tires are very nice, just stickier at the moment.

What kinda impact is normal? I'm down 3 to 4 mpg.

TDiSkater said:

Just got some new Michelin tires LRR MXV4 Primacy. Looks like this tank is coming in 3 mpg down from recent averages. I took pressures up to 85% max to see if I can get back on track. Do new tires need to break in a bit? If not, then I need to look in other places.

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The answer is absolutely yes. The best is to take it very gently for a minimum of 500 miles. 43/44 PSI (85% of max 51 psi pressure) is a great place to start. How gently you break them in can have a great effect/affect on longevity, IF that is one of your goals. All things being equal (let me be one of the first to say they seldom are) a new tire will lose 1 to 3 mpg .

I'll just add that every so often, take your TDI on a reeaaaallly long highway ride...talking 2-3 hundred kilometers of non stop 120Km/h speed. Mine ran like a top after a jaunt down to Windsor.

I love the cetane ratings. Thanks! I had no idea they varied so much.

Why not putting additive in 2.0 CR TDI ?
I am running one ( Jetta 2009 ) and always added Stanadine up to recently, I changed to Lube Corp Premium diesel Plus. I can only observe benefits. Is there a negative effect of putting additive or the engine can manage without ? Thank in advance for your reply.

I have a 2012 jetta tdi 6mt.
18,000 miles now. My overall mpg average for all tanks is 47.5mpg.

Things I do and have done.
After 1500 miles, drove it like I stole it from every stop. Many times skip shifting from 3rd to 6th or 2nd to 4th.
I run tire press at 44-45 psi all times.
I add stanadyne lubricity 2oz to every tank. I also add the grey bottle clean disel to each tank to boost cetane some. I'm in NY and cetane is low at 40 max.
I have filled up at same station 93% of all fill ups. It's a high volume truck stop on Indian res.
I run low revs while cruising. 1200 rpm very common.
I have hills to climb and will climb steep ones at 1800-2000 rpm.
On down side of hill I let engine braking rev up engine to 3500 rpm.
On long easy downhills I coast in neutral.
I drove to Rochester today from south buffalo. Some tail wind, 70mph highway and some drafting. 60mpg on daily trip Meter. Drafting several car lengths behind a truck was good for 2-3 mpg for sure. 15 miles with a/c on. (I don't like running a/c as it really affects mpg. Good 2 or more drop in mpg). On way home I expect head wind and predict return trip mpg to be about 54.

This car exceeded my mpg expectations. I think my hard break in helped it. I checked intercooler during my oil change and it was free from any trace of sludge or oil. I do not burn oil at any measure able amount. At 12000 miles, I drained out just less than 5 quarts. And I put back in the diesel type of Mobil 1 10w-40. Oh my!!! The oil that is supposedly just shy of meeting VW requirements. Except for the pan removal, oil change was easy. I'll do it myself.

Hey! Hello all.

I am new to the site and really new to TDI's. Wanted one forever and finally got one. 2009 Jetta Sport Automatic. had 67,000 when I got it now 69,500. Point is I have for the past 7 years owned a Golf 2.0 gas, avg 33 mpg with larger tires at 40psi and Lrr at that. Now I a, getting 39 to 47 in the Jetta. love the car and all. Looks cool, drives better than the ole' ladie did. But I want more MPG. Recently went to Virgina for the weekend from Cleveland, Ohio down 77 then NE to Roanoke. Avg. with the windows up and AC on at 70 to 75mph was only 38mpg. Is this normal? Or am I just experiencing the reality of what these cars do? I am not a "hyper miler" though I do appreciate the anal folks for all their efforts.... But I was hoping for more. Are the breathe and exhaust Really going to add more? Or are the folks here just reporting these claims just representatives of the manufacturers for ALL these "add-onz"? I am a real skeptical fella. Just asking a real question. Not meaning to offend. Though my Wife says I always do So sorry if I do. It's a genetic fault.

The A/C just kills the mpg. If you can stand it crack pass front and rear about 1.5" with no a/c and you will do considerably better. Look at wind direction, if headed into wind with ac on at 76 mph, 40ish maybe all you get.

I cruise 68 without ac and get 48-55 depending on wind direction and strength.

Jbdesigns said:

The A/C just kills the mpg. If you can stand it crack pass front and rear about 1.5" with no a/c and you will do considerably better. Look at wind direction, if headed into wind with ac on at 76 mph, 40ish maybe all you get.

I cruise 68 without ac and get 48-55 depending on wind direction and strength.

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I may not currently have AC in my house in FL - and it has been hard, but there is no way I can do without the AC in the car. The humid air flowing in drives me INSANE.

I"m bummed it is helping bring my mileage down - but some things a girl just has to suck up and deal with! LOL!!


All that aside - I have to say i'm completely and totally LOST in this whole fuel area. I'm still trying to sort out what i'm looking for in where to go to fill up, what to do once I get there... at least I have my handy dandy gas cubby app. I'm good at that part!

IS there a FAQ type of list of things to do when fueling? That lists stations to avoid/go to? A way to convince me to fill up sooner as opposed to on the way to an appointment which means no time for foam to settle....

UNsweet said:

IS there a FAQ type of list of things to do when fueling? That lists stations to avoid/go to? A way to convince me to fill up sooner as opposed to on the way to an appointment which means no time for foam to settle....

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There may be one somewhere but I think the best piece of advice about fuelling is to simply avoid stations with low turnover. If you've never seen a dump truck or a big diesel truck filling up there, chances are their fuel isn't the freshest. Other than that, I've always shopped by price (also with Gas Buddy) and things work out OK.

Tom Servo said:

There may be one somewhere but I think the best piece of advice about fuelling is to simply avoid stations with low turnover. If you've never seen a dump truck or a big diesel truck filling up there, chances are their fuel isn't the freshest. Other than that, I've always shopped by price (also with Gas Buddy) and things work out OK.

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Most of the stations i'd go to are high turn-over. My ex is/was a truck mechanic - I know what to look for in that area! It might be the ONLY thing I know!

What about adding crap? That apparently relates to the quality of fuel... the Hess I filled up at the other day had a 40 cetane sticker on the pump. The best tank was on the Murphy stuff I panicked and filled up with (I was running late and stressed about leaving a couple of kids home alone and figured running out of fuel on top of it wouldn't be a good thing! LOL!!).

I really need to make the appointment with the guru for an inspection. The problem is that it is now 7 days until school starts and I have no idea where my daughter will be going. Which makes it hard to schedule an appointment.

Maybe I should go research antibiotic over-use and write that thing up for school instead of avoiding it?!?!

UNsweet said:

Most of the stations i'd go to are high turn-over. My ex is/was a truck mechanic - I know what to look for in that area! It might be the ONLY thing I know!

What about adding crap? That apparently relates to the quality of fuel... the Hess I filled up at the other day had a 40 cetane sticker on the pump. The best tank was on the Murphy stuff I panicked and filled up with (I was running late and stressed about leaving a couple of kids home alone and figured running out of fuel on top of it wouldn't be a good thing! LOL!!).

I really need to make the appointment with the guru for an inspection. The problem is that it is now 7 days until school starts and I have no idea where my daughter will be going. Which makes it hard to schedule an appointment.

Maybe I should go research antibiotic over-use and write that thing up for school instead of avoiding it?!?!

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Additives… oh my that could start pages and pages of debate. I guess it comes down to personal preference. I had a 2000 Golf which I ran additives in from time to time and noticed zero difference in performance or mileage. Unfortunately I didn't get to own it long enough to see if additives would have affected longevity.

I have a 2005 now with the 100 hp BEW motor and haven't run additives but once in a blue moon over its 287,000 miles. It didn't seem to make a difference in obvious signs like smoking, acceleration or mileage, or at least not enough to justify the cost of the additives!

What I *have* found is that some stations' fuels smoke less and give better mileage than others, and it's completely arbitrary. Meaning I've had to find "new" brands to try each time I've moved. Texaco and Shell in Birmingham (AL) smoked like the dickens so I didn't use them. But Shell here on the Gulf Coast seems to be one of the better fuels. When I lived in Mississippi I tried to use their local B20 biodiesel from Scott Petroleum as much as possible. It didn't smoke even under full throttle but the mileage was just so-so.

For whatever reason I seem to get the best mileage from the fuels that tend to smoke more, like Murphy USA and CITGO/Tom Thumb. Chevron seems to be the exception in that it's given me some higher mileages and less smoke, but it's priced so high I don't buy it. And I've tried Chevron in other parts of the country and it's performed very poorly. More than anything though I buy on price and turnover, and haven't run into any trouble yet that I'm aware of. I've never found water in the filter or anything, or trash.

Now go work on that antibiotic paper. The more people you can convince to stay away from antibiotics unless they're seriously ill, the better for all of humanity.

Tom Servo said:

Additives… oh my that could start pages and pages of debate. I guess it comes down to personal preference. I had a 2000 Golf which I ran additives in from time to time and noticed zero difference in performance or mileage. Unfortunately I didn't get to own it long enough to see if additives would have affected longevity.

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LOL... i figured that - because there is already pages and pages on it!

Thanks for your experience.

What I *have* found is that some stations' fuels smoke less and give better mileage than others, and it's completely arbitrary. Meaning I've had to find "new" brands to try each time I've moved. Texaco and Shell in Birmingham (AL) smoked like the dickens so I didn't use them. But Shell here on the Gulf Coast seems to be one of the better fuels. When I lived in Mississippi I tried to use their local B20 biodiesel from Scott Petroleum as much as possible. It didn't smoke even under full throttle but the mileage was just so-so.
For whatever reason I seem to get the best mileage from the fuels that tend to smoke more, like Murphy USA and CITGO/Tom Thumb. Chevron seems to be the exception in that it's given me some higher mileages and less smoke, but it's priced so high I don't buy it. And I've tried Chevron in other parts of the country and it's performed very poorly. More than anything though I buy on price and turnover, and haven't run into any trouble yet that I'm aware of. I've never found water in the filter or anything, or trash.

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I've tracked MPG in most cars i've driven - so i know what you are talking about. Smoke - would I be able to notice the car smoking? Because I don't think it does - but i'm not looking for it... and I haven't seen any soot up the back either. The Chevron here in my town doesn't seem like a high turnover station (seriously, we have tire shops and gas stations, it is nuts when you ponder the size of the town), so I will probably avoid it. I figure I should get some sort of feel soon - i've gone thru 3 tanks in 3 weeks and am a little over a 1/4 done with the next one. Ye gads.... no wonder the budget is blown. Again.

I'll just keep using my app for now and remember to check the tire pressure. Why do I always remember that when I can't check it?!

Now go work on that antibiotic paper. The more people you can convince to stay away from antibiotics unless they're seriously ill, the better for all of humanity.

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Wasn't a full paper... just a discussion post. All done.

But I did highlight the child that ended up in the ER with peri-orbital cellulitis from a "refuse to treat" sinus infection. Twice. Took two times because we were given an ENT referral. I'm a horrid HMO patient/mom. I'm all for only using it only when needed - but when it is me that is facing the school board because I have a child out for 25 days in a year... well, work with me doc. Please. (i'm trying to change peds, and it was my special needs daughter so they ignored it and passed her on to the next grade anyway).

If I coast down hills in neutral, then put it back in drive with my DSG at highway speeds, will I cause any damage to the DSG tranny?

bockegg said:

If I coast down hills in neutral, then put it back in drive with my DSG at highway speeds, will I cause any damage to the DSG tranny?

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As long as you are very careful not to engauge the throttle until the car is completely back in gear you should be ok.

bockegg said:

If I coast down hills in neutral, then put it back in drive with my DSG at highway speeds, will I cause any damage to the DSG tranny?

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I would like to know more about this. I too have a DSG Transmission and when attempting to "hyper-mile" I find that the engine brake created while coasting in gear significantly slows my coast. While doing the same coast in neutral provides a much longer coast. But, inevitably, the kinetic energy drains and you need to accelerate. Does shifting from neutral into drive affect the transmission? When I have done it, not over 30 mph, I shift back into drive and wait for the revs to catch back up to whatever gear the car should be in, then apply the accelerator. I would assume that this is better than shifting and instantly stepping on the accelerator, but I'm unaware of how the whole action affects the transmission or any other piece of the car. Can someone shed some light on this?

I think the "coast or engine brake" debate could rage on forever, at least for manuals. I used to coast all the time, but a few years ago I got in the habit of using engine braking to slow the car. I'm not sure my mileage has actually changed any.

I'm not using any fuel when engine braking (so sayeth the forums, anyway) but those slowing periods are shorter than coasting. But while coasting, the engine is consuming fuel at a very small rate if the engine is idling. Personally, I think it's a wash. I have no idea if the DSG is any different.

I live on the NW Coast where its hilly and the temp stays very close to the same (60ish). My N75 valve didn't work for some time and I'd always pull certain hills at certain speeds. If I forgot to add the additive I use (Diesel Clean I believe) not only do I loose 3-4 Mpg but I'd loose 5 MPH going up the same hills. I have no doubt diesel additives work (and pay for themselves). Now that my N75 works I can take the hills however I want..
I get an average of 47 MPG, but I don't drive very conservative..

Great info, thanks.

Might there be a list somewhere of cetane ratings for diesel stations along the eastern seaboard?

Also, how do you come down on the use of nitrogen in tires to increase mileage and which reportedly have less leakage or oxidation on the tire than air? Cost effective?

Thanks,
Dave

deliassen said:

...
Also, how do you come down on the use of nitrogen in tires to increase mileage and which reportedly have less leakage or oxidation on the tire than air? Cost effective?
...

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Nitrogen in tyres = mostly snake-oil (apart from perhaps formula 1). After all, air is mostly nitrogen already. The main practical difference is that there is less moisture in the nitrogen fill compared to the normal air fill.

Thanks. Tire Rack advises most drivers would be better off monitoring tire pressures better.

+5 MPG by removing intake duct

I have been chasing down low mileage since I bought my Passat last year. My Passat has the BLOCKED front grill where the air intake duct attaches.

See: http://i227.photobucket.com/albums/d...ers/fbbe_3.jpg

Here is the complete thread,
http://forums.vwvortex.com/showthrea...Passat-ram-air

I removed the intake duct and the two other ducts in the lower left corner of this picture. My highway mileage has improved by at least 5MPG according to the instrument panel MPG gauge. I wont know the actual number until my next fill-up.

Eventually I'll cut out each little rectangle in the grill but that project will have to wait for now.

Cheers,
Erik

TDi Erik said:

I have been chasing down low mileage since I bought my Passat last year. My Passat has the BLOCKED front grill where the air intake duct attaches.

See: http://i227.photobucket.com/albums/d...ers/fbbe_3.jpg

Here is the complete thread,
http://forums.vwvortex.com/showthrea...Passat-ram-air

I removed the intake duct and the two other ducts in the lower left corner of this picture. My highway mileage has improved by at least 5MPG according to the instrument panel MPG gauge. I wont know the actual number until my next fill-up.

Eventually I'll cut out each little rectangle in the grill but that project will have to wait for now.

Cheers,
Erik

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The grill opening is closed for several reasons, a closed grill vent gives Longer filter life, gives some Engine noise reduction and lowers Emissions output ( less cold fresh air gives lower NOx ).

This engine was detuned for the US market to pass emissions so really doesn't require the vent be opened to give stated output rated power.

First, a closed vent helps in keeping the air filter clean longer increasing the rated filter life time and mileage rating range. Diesel engines suck in large volumes of air compared to their gasoline counterparts, many times that of their gasoline counterparts. So it can clog up quickly in adverse conditions. A closed front air ram vent can keep this from happening sooner in the filter life. Americans are notorious for ignoring maintenance so a long filter life was a must for the US market.

Second, a closed vent lowers overall engine noise from in front of the car, cars have a maximum allowed noise limit. VWofA has been using this trick here in the US/Canada for decades on diesel powered models to lower engine noise. VWofA figured diesels were a hard sell outside of the VW diesel die-hard market. So to increase sales numbers here to include other than the diehard diesel market the vent was closed. For VWofA to consider bringing a diesel powered model to the US market it must have wider sales appeal which the closing of this vent gave.

Third and likely the main reason the duct was closed was that fresh cold air increases from a open air duct is denser. Denser air gives more power from more complete combustion which leads to higher N0x levels. This car was really close to N0x limit and a open grill more than likely caused the car to fail emissions. Closing the vent lowered power( the engine was already detuned for the US market to pass emisions ) and it lowered N0x emissions to help pass our stupid emissions rules.

You will see better throttle response at speed with the duct open and you will see higher mpgs. But N0x emissions will be significantly higher and air filter life will be shorter if you are exposed to dirty or wet conditions.

I made this modification to a friends 04 Passat TDI a while back and he clocked a 3-5 mpg increase also, biggest increase in mpgs was on the highway at higher speeds. The car is however now louder if you are standing right in front of the opening while running.

A precaution that must be taken into consideration is that you must keep closer tabs on the air filter cleanliness. A look-see air filter and air box inspection ever so often will be a must once this mod is made. Once this change is made if you drive through dusty conditions or in very wet conditions you must inspect the filter for damage or clogging issues regularly.

Okay so not sure if these have been discussed but here are some of the tips I have found that help me.

I don't shut my car off at lights because I have found instances on where I need to get moving and its been good to not have the car shut off. But I do however since it is faster and it has seemed to help is put the car in N while at a light since I have the DSG. This site actually says to do that at long lights any how in the precautions part of the article. http://www.dctfacts.com/archive/2009/mitsubishi-evo-x.aspx

I back in and avoid multiple maneuvers a lot.

I inflate my tires to the max pressure maybe only 2-3 pounds less. I also haven't noticed any adverse tire wear problems because of this.

I make sure I am ready to go before starting the car meaning everything is adjusted to my liking before leaving.

I am also losing weight around my waistline which has many more benefits than just efuel economy too.

There are a few other ones I have not tried that I have seen around like shutting the car off before putting the car in park. Lower the car with lowering springs. I have even seen some say to increase thermostat temps, take off cold air boxes, lower vis oil in engine, transmission, and differential. But a lot of that sounds like bro science to me. Or even if it does work I would hate to squeeze out a few extra mpgs to decrease the protection of my oil and fluids.

But speaking of fluids here is something that is suppose to help in fuel consumption.

http://www.evanscooling.com/

berserkerx said:

I am also losing weight around my waistline which has many more benefits than just efuel economy too.

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Since owning TDIs, I've lost (and re-gained) over 100 lbs through the course of recent history, and I can honestly report that it has not affected mileage in any noticeable way. Or if it has, it's been negligible. I've done a regular commute at two vastly different weights and also some major trips (like AL to CA and back) and haven't noticed a change.

It wasn't until a few years ago that I began hauling around two extra full size people on a daily basis that I noticed a real hit on economy, especially on trips. I actually get lower mileage on the interstate at 70 than I do on our local back roads at 45.

Fuel consumption while idling

Tom Servo said:

But while coasting, the engine is consuming fuel at a very small rate if the engine is idling. Personally, I think it's a wash. I have no idea if the DSG is any different.

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I checked the fuel consumption with VCDS at ide on my 2010 JSW w/DSG. Also with and without A/C on:

IDLING NO LOAD 0.63 l/h:
828 /min Engine Speed (G28)
41.4°C Fuel Temperature (G81)
15.0 High Fuel Pressure Control Status
828 /min Engine Speed (G28)
0.0 % Accel. Pedal Pos. Sensor 1 (G79)
0 01 0 Operation Status
94.5°C Coolant Temperature (G62)
33.0 Nm Engine Torque (actual)
0.63 l/h Fuel Consumption
0.0 Nm Torque Request (Driver)

IDLING WITH A/C ON MAX, FAN ON 2: 1.05 l/h
46.6 % Generator Load
00000001 Auxiliary Heating Shut-Off Conditions
0.0 Heating Element Activation
13.45 V Supply Voltage (Terminal 30)
828 /min Engine Speed (G28)
0.0 % Accel. Pedal Pos. Sensor 1 (G79)
0 01 1 Operation Status
90.0°C Coolant Temperature (G62)
828 /min Engine Speed (G28)
54.0 Nm Engine Torque (actual)
1.05 l/h Fuel Consumption
0.0 Nm Torque Request (Driver)

Shifting from N to D on DSG while driving

bendles said:

I would like to know more about this. I too have a DSG Transmission and when attempting to "hyper-mile" I find that the engine brake created while coasting in gear significantly slows my coast. While doing the same coast in neutral provides a much longer coast. But, inevitably, the kinetic energy drains and you need to accelerate. Does shifting from neutral into drive affect the transmission? When I have done it, not over 30 mph, I shift back into drive and wait for the revs to catch back up to whatever gear the car should be in, then apply the accelerator. I would assume that this is better than shifting and instantly stepping on the accelerator, but I'm unaware of how the whole action affects the transmission or any other piece of the car. Can someone shed some light on this?

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I really would like to see some more info about this too. Is it too bad for DSG to shift from N do D often? My feeling is that as long as revs of the transmission and engine are not too far apart in the moment of shifting to D it's not bad. But when the revs are too different it probably wears at leas the clutches. So, at 40mph and below I just shift from N to D without stepping on the gas pedal. But over 40mph I raise the engine rpm a little bit, trying to match the revs. For example I know that at 60mph engine rpm equals 2000. So, at 60mph I try to raise the engine rmp to aroung 2000 before shifting from N to D and it shifts smoothly. I think it is a good practice.

Jagerbecher said:

I really would like to see some more info about this too. Is it too bad for DSG to shift from N do D often? My feeling is that as long as revs of the transmission and engine are not too far apart in the moment of shifting to D it's not bad. But when the revs are too different it probably wears at leas the clutches. So, at 40mph and below I just shift from N to D without stepping on the gas pedal. But over 40mph I raise the engine rpm a little bit, trying to match the revs. For example I know that at 60mph engine rpm equals 2000. So, at 60mph I try to raise the engine rmp to aroung 2000 before shifting from N to D and it shifts smoothly. I think it is a good practice.

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I have actually read in the manual that if you 'accidentally" knock the car into N to wait till the rpm goes down to idle speed and then put it back in D.

berserkerx said:

I have actually read in the manual that if you 'accidentally" knock the car into N to wait till the rpm goes down to idle speed and then put it back in D.

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True. So my wife can do it too, with little practice... If you know what I mean.

I bought my Golf TDI 6MT in July this year and I absolutely love it! I stumbled on this thread shortly after taking the car home and followed some of the tips and tricks posted here with what I think are some good results. I don't really have a history with TDI vehicles so I can't tell if my mileage is just great in general or as a result of following the tips on this site but I can report that I've just completed a 4000+ mile test of GasPods http://www.gaspods.com (I know, silly name since we drive diesels), and I've measured a near 6% increase in fuel economy. My boss actually forwarded the site to me after hearing that I bought a fuel efficient vehicle. Of course after getting the TDI I would come into work each day beaming about my cars computer registering 52 MPG for the commute in, etc. My boss took notice and I think in sort of a mocking gesture sent me a link to the GasPods site and said maybe I can get even better fuel economy. I laughed it off at first but then started reading about turbulators in general and saw the science behind it. I also noticed that the GasPod makers were looking for test subjects. Since they offered a discount for test subjects and I had already logged 2000 miles on my TDI with fuelly.com I decided to apply and test these things out. This of course after also reading a couple of threads on here speculating that they are snakeoil so I was skeptical at first but since the people calling it snakeoil on here hadn't tested them and they were only speculating I decided to give it an honest try. Like I mentioned, I was already using fuelly.com and following some advice on this site in an attempt to squeeze as much fuel economy as I could out of this car (I was already impressed coming from a max 28 MPG car previously, MazdaSpeed 3, but wanted to see how far it would go). My first 2000 miles on fuelly before even hearing about the GasPods I was disappointed that I couldn't break 50 MPG for my full tank average. I did however have the data already to get a discount on the GasPods so I ordered them and continued monitoring my fuel economy with fuelly for the next 2000 or so miles. I broke the 50 MPG barrier easily and was absolutely ecstatic. Apparently these reduce the net drag on the car when driving 35-MPH or over by causing turbulence at the point of separation of airflow over the car (I have no idea if I described that properly). The turbulators (GasPods) add a tiny bit of drag on their own but relieve much more by breaking up the flow of air at the point of separation. Unless by some miracle my fuel economy increased that much at the exact time I started using GasPods I have to conclude that they do legitimately work.

I wanted to share this since there seem to be a lot of folks on here looking to save fuel and my test of these conclude IMO that these do, over and above the others things I've tried from this forum. At the discount I received I should recover my purchase price in about a year which I think is quite fair. There were other benefits for the 'think green' types like CO2 footprint reduction and water savings due to lowering fuel consumption. This wasn't something I initially paid attention to but I guess it's also nice to know I'm reducing my carbon footprint further.