For all you guys/gals that are gassing it up, how much did your mileage change? Is it worth doing if you add the cost of Propane to your mpg calculations? I'm considering it, but wanted to hear what has happened to you boys and girls who have done it. I have the J/A, does that make a difference too?

Chris, the added price of the propane makes up for the diesel that you save. Now if Diesel goes outta sight and propane stays cheap? who knows

a64pilot,


Do you have Propane on your truck? Did you see any mpg increase?

I see slight MPGs improvments (1-2), but then again, I didn't get propane to go 55.

I've run propane on my cummins and my dmax for four years now. At first I tried using it for economy but once you run it with a big box you'll forget about the economy real fast. I think if I had one of those ricer wings on my truck the highway would turn into a runway!

http://www.dieselplace.com/forum/smileys/smiley36.gif I just need some justification and economy seems to work really well on the wife. If you get 1-2 with more foot in it, then .......http://www.dieselplace.com/forum/smileys/smiley2.gif

Okay, second question. How many gallons of propane per gallons or fuel or miles driven? What do you guys normally pay for propane and where do you get it? Can I just go to U-Haul and fill the truck when I fill my 20 lb jugs for the grill and mosquito magnet?

My way of looking at the economy thing is this:





Modify for performance and efficiency. If you gain MPG that's great, but if you have great expectations for economy gains, you'll likely be disappointed.





This also hold true for 90% of those buying chips for the MPG gains...

jk - what are your thought about running propane...ive been thinking about it for the torque and MPG when pulling my toy hauler which seems to be every weekend and - what are the pros and cons, and how does the engine and tranny do with the added propane ?

Chris,


Personally no I'm sticking with D2 for now although I might supplement the 02 side of the house if needed. Legally if you use it you have to pay highway tax. Your propane supplier may be smart enough or not I don't know. I would stick with the tale that the tank suppplied my RV if asked. Not a real good comparsion but propane supplies half the BTU's as gasoline. In other words it's taks 2 gal of propane to travel the same distance as 1 gal of gas will carry you. The best reason you don't see many propane fueled vehicles, except warehouse forklifts. You would probably never recoup the expenses from mileage increase. John summed it up pretty well. If you need to sell the better half on it it's not hard to find alll kinds of mileage claimshttp://www.dieselplace.com/forum/smileys/smiley2.gif

Propane in moderation is ok, but I think you'll find that many of the Dmax engine failures had propane in the recipe...





I went with the Powershot for name, reputation, and simplicity. I haven't put one on my truck yet, and may never do so other than for testing, but then you never know...

Technically, since the vehicle is not ever running on propane,nor is enough injected to even start the vehicle, road taxes should not be required. It would be the same as say filling a nitrous bottle or water/meth bottle. Just an additivehttp://www.dieselplace.com/forum/smileys/smiley2.gif In a true bi-fuel or dual fuel application, you would be subject to them as it is used to run the vehicle at some point.


Actually more and more propane powered buses, and company trucks are being used. Schwanns food delivery is one of the larger ones that comes to mind.


Most people see between 500-600 miles of constant use, out of a 20 lb tank which is approximately 4.5 gallons. Any filling station will fill your tank, such as a UHaul. Many Flying J's also have filling stations as well now, so it is readily available.

JK,


I know not to expect it, but I have to have something to SELL it. http://www.dieselplace.com/forum/smileys/smiley2.gif Throw out some numbers where I can recoupe the cost in a couple of years, blah, blah, blah.


PS1,


Thanks for the carification. The yo-yos at my u-haul are lucky to find up in the bathtub.http://www.dieselplace.com/forum/smileys/smiley36.gif I have yet to have the same person fill my tanks twice and I go about every 6 weeks.http://www.dieselplace.com/forum/smileys/smiley3.gif


Do you set up the system to come on when you crank the truck, but have a switch to shut it off if desired?


Chris

They are preset from the factory for each brand truck. Dmax's have a 5 psi start time, so system on, under 5 psi, nothing happens so most people just leave it on all the time. Once you hit 5 psi it starts flowing and the amount of propane increases almost instantaneously as the boost pressure does. So it is very driveable power, and economical on propane usage as well, as it is not always full flow on or off. It does have on on/off switch as well. You do not want any propane flow unless there is some boost pressure present. 2 psi is about the soonest you would want it to come in.Edited by: powershotone

JK,


Since I have the J/A, I would want to stay with a tame or standard setting and even turn down the Juice from the 4 I leave it on now. I don't want to toast the tranny just yet, but I figure I will do something in a year or two. Haven't figured out how to sell that one just yet.http://www.dieselplace.com/forum/smileys/hihi.gif I seem to do okay as long as I stay below $1K, so the tranny has to wait a bit.


Chris

SDaver's probably got the most stacking experience here. I know that he runs his a good bit.

chuntag95,


I put LP on my Dmax at 500 miles, now have 6600. I use alot, but that is by choice. I get it for $1.09. I can't give you definite consumption #s yet because I don't have a meter on my tank that I fill my truck from. I took it to Dallas last month and used 60 or 70 gals of it, which is probably around 35 mpg on LP. The diesel mileage was 30 at 75 mph, so it is near double what it would be straight diesel. I am going to put a 10 lb bottle in on my next trip, weigh it before and after, and get some solid numbers. At that LP price, if I am getting 35, it is saving me $.01/mi, which isn't much, but adds up. Plus, my oil looks brand new, the motor is quieter at highway speed, and it makes great quiet power. PM me if you want more info. My setup is sort of homemade, all components are from gasoline LP conversion, and very available. BTW, propane has 30% lower BTUs than gas, gets 20% less mileage than gas, not 50% that was stated above. I have burnt tens of thousands of gals of it in gas motors. I think that if Dmax motors blow on LP, it's because they are being pushed way too hard, because LP will add alot of power.

I just wanted to clarify that I did not mean my comments to sound like propane killed engines. What I meant was that propane was in the recipe for destruction if not used wisely. This also can be true for water/meth, nitrous etc. I believe most of the catastrpophic failures contained a "witches brew" of unnatural components to diesel combustion...

I put water injection on a gas motor about 16 years ago to combat a pinging problem. It worked really good. It came on at 9" vacuum and sprayed into the carb throats. I eventually rebuilt the motor because the cam was failing. When I took it apart, I couldn't believe all the calcium deposits on the exhaust valves. It never occurred to me that I should have been using distilled water. It didn't seem to have hurt anything, but I can't imagine calcium doing the cylinder walls and rings any good. I'm sure it would do the same in a diesel.

To appease your wife...


Tell her that propane is 1.09 a gallon. Let her make the assumption as to what the savings would be.

lp and 90 Juice is incredible together. Add attitude and I can't comment.

I was fishtailing with the two together just flooring the pedal.

I ran lp for probably 50,000 miles. Came on at 2psi. Makes it run sooo much smoother. But

I have no idea what you will find LP to cost in small quantity. I have seen it at Flying Js for $1.49 or $1.59. I never buy it except in large quantity, unless we are in Canada on vacation. We took my '91 to Nova Scotia this summer pulling our 5er. It runs on LP or super. LP was $2.50/gal (this is after exchange conversion), gas was over $3.00. My rig got 6.9 mpg on lp, 8.5 on gas. I had two LP fillups that cost me $250 american each, and I could use that up one tank (100 gals) in one day of driving. Now you know why I got a Dmax. Edited by: marcdeluca

Hoot,


"But" What?http://www.dieselplace.com/forum/smileys/smiley5.gif What kind of mileage change did you see with propane vs. stock?


I was going to call U-Haul and see what their price is per gallon. I might just go by since I need 2 bottles filled.


I did tell the wife I thought I might know what my next mod would be. Can add 2-3 mpg and her response was WOW. http://www.dieselplace.com/forum/smileys/smiley32.gif Haven't discussed price yet. http://www.dieselplace.com/forum/smileys/smiley2.gif

lp and 90 Juice is incredible together. Add attitude and I can't comment.

I was fishtailing with the two together just flooring the pedal.

I ran lp for probably 50,000 miles. Came on at 2psi. Makes it run sooo much smoother. But


HOOT - wheres the rest of the info ??? come on, youre leaving us hanging here eh - ?? no comment on adding attitude ?? runs smooth - but ??Edited by: tbone1227

After the holeshots I was blowing coolant.
I purchased my lp from a big distributor in NJ as motor fuel. At first it was $1 a gallon but was about $1.30 this spring. I never really looked at mileage gains as I knew I was on the pedal more. The average is 25 % lp to diesel.

I read somewhere that you can run as much as 85% LP or CNG to 15% diesel. They are doing this in city buses, but it takes electronics to do it. Stationary engines with constant loads would be alot easier. The mixture has got to be kept lean enough to keep from igniting under compression. Just enough diesel fuel is used to ignite the vapor fuel. The goal in these cases is purely emissions. On my truck, I found that with almost 50% lp the cruise control had a hard time keeping the truck at a steady speed, because so little throttle was being used. I closed my state of the art ball valve (between the regulator and intake pipe) a little bit and cured that. Probably dropped my diesel mileage some, but the hunting was driving me nuts.

Wouldn't decreased lubricty become an issue at some point?

I run my LP all the time for 60,000+ with no problems. Never any problems with just Juice and LP for 40,000 of it. Do you think there could be a lubricity problem Toni (Max P)? Curiosity has me now. I know about the water/meth lubricity problem (GM test), but that takes about 150,000 miles to show up (with constaint use), and it is very minimal.

Wouldn't decreased lubricty become an issue at some point?


Shouldn't be a problem for the fuel system. I have heard that propane is a "dry" fuel as far as the cyl walls are concerned, but surely that is at much higher levels than Chris is looking at. I also believe that too much propane will detonate an engine to death, but surely again that is at much higher levels than a street truck would run. One of the issues I believe is to ensure that it is turned off and no possible flow can occur when the truck is off. Another reason to not build your own unless you are very familiar with it.

Dump propane in and add timing box.... not good. Propane advances timing. Instability occurs because you really can't control timing with propane like you can with a box.

I think in moderation lp is fine. It's only fumigating the intake air. Not enough to cause any dryness issues or lubricity issues in my opinion.

Whatever you do you CANNOT accidently dump liquid lp into the intake. Small quantity will evaporate inside the intake tube but that turns into a load of gas. Larger quantity will hydrolock it.

Regarding lubricity, it is only a potential problem for the valves and seats. The cylinder walls like dry fuels, because the fuel doesn't dilute the oil film. This is why lp engines last up to 4 times longer than gasoline engines. With hard valve seats and good valves, the dryer fuel doesn't have much effect. Besides that, the diesel that you are sill burning will add lubricity to the valve sealing surface. Years ago, some truck engines that ran on LP had an oil drip that put oil into the intake at a low rate to keep the valve seats from receeding, but today the materials are much better.

This is turning into a really informative thread. http://www.dieselplace.com/forum/smileys/smiley32.gif I am looking at lower levels of propane for now. I would like to get some efficiency and some power. I might even pull off the J/A and put my SPA back in if it warrented it. It's a WHOLE lot easier to pull the Juice. I would need to keep the propane system where I can get it off and at least lock it up in the bed should I have a failure that left me stranded. I doubt it will ever happen, but I do still have a couple of years of extended warranty and then the 100K engine. (I do keep a panel in the consol for the Attitude to disappear from the overhead if needed.http://www.dieselplace.com/forum/smileys/smiley2.gif )


I know the Juice/*** has timing even on the zero setting. Can you get the Juice w/o timing if you want to stack to two? Since I don't have the hot, will running on say 2 or 3 with propane anyway, would that be fine? I don't baby the truck, but I don't thrash it either. (I can't afford to put on good tires every month.http://www.dieselplace.com/forum/smileys/smiley36.gif)


As usual, you guys ROCK when it comes to getting good info. http://www.dieselplace.com/forum/smileys/Rock On.gifEdited by: chuntag95

speaking of warranty work, how does gm look at propane in regards to warranty work ? im thinking about it but dont want to unhook everything for every trip for warranty

The Powershot 2000 is SO simple to do a basic install with. About the only technical thing is getting the boost psi source to drive it. From there, point of entry can be through the filterminder. You'll also need to wire the "lock off" solenoid for safety...





If GM knows about it, it will likely be blamed for everything from brakes/rear end, poor AC performance etc. so Out of sight = out of mind applies here.

Warranty is a big concern. I think this is going to depend on the dealer. I bought my truck locally and have a pretty good relationship with them. I explained to the parts manager that I did the lp for mileage and emissions, and not for power. I have concerns about breaking down away from home and going to another dealer. Mine would be a bit more difficult to remove since it is tied into the heater hoses, but my tank is the big problem. I hope that if the motor gives any trouble, it will be related to the diesel fuel system and can't be blamed on lp.


Another observation that I have made is that apparently the algorithm that computes the oil change interval is based on an input of fuel use. Since I use alot less diesel, I think it prolongs the time between oil change notification. My Snap-On scanner will show me the percent left on my oil. I checked the other day, and at 6400 miles, it is still showing 36%, which makes me think that it won't notify me to change until 10K miles. Do any of you let the counter go until it notifies you, or do you reset it when you change it?

I was told not to put lp in ahead of the Mass Airflow sensor. The oil in the propane can foul the sensor, much like overoiling a K&N filter. I put mine in just ahead of the turbo, in the airpipe. It is plastic, really easy to drill and tap.

I was told not to put lp in ahead of the Mass Airflow sensor. The oil in the propane can foul the sensor, much like overoiling a K&N filter. I put mine in just ahead of the turbo, in the airpipe. It is plastic, really easy to drill and tap.





Good point. I believe that Hoot was one of, if not THE first Powershot users on a Dmax. His was on already in September 2000 IIRC.





If memory serves, he snaked his feed hose past the MAF, but also found the need to tie it down so it did not affect air flow around the sensor.

I saw the install instructions on the PS2K and it shows going through the filter minder and down the pipe past the MAF sensor. Probably for the same reason mentioned. That would also allow you to pull the tube out and pop the filter minder back in for a no damage shown removal if needed. At 100K, DILL and TAP BABY! I guess the other option is to get a second tube. I don't want to have THAT many spare parts in the truck to hide my evil ways.http://www.dieselplace.com/forum/smileys/smiley15.gif


So, for folks with the PS2k, how many miles between tank fills for the 8 gallon tank? Some of the numbers I have seen suggest about 1000.

Hoot,


How did you "tie it down"?http://www.dieselplace.com/forum/smileys/smiley5.gif


JK wins the race.http://www.dieselplace.com/forum/smileys/smiley36.gif

I would go along with that milage (800-1000). I also agree, out of sight out of mind. The PowerShot is the one I recommend fully for easy of install, reliability and control of charge. Not to mention for big power (in combo) if that is your cup of tea.

The inline intake manifold I make that goes inside the post I/C tube is a good place to plumb for boost pressure and incepting the charge line (or what ever else you want to plug in). If any interest, please PM me. I am working on one for the LLY as well.

I just drilled the intake tube with a hole small enough to self tap a fitting...



http://www.uscom.com/%7Ehoot/cars/duramax/gmc/propane/fitting/images/DSCN3099.jpg

Is that the tube that comes stright off the air box Hoot?

Just called U-Haul and they want $3 a gallon!http://www.dieselplace.com/forum/smileys/smiley3.gif I will have to find a cheaper source for this to work out. How did you guys find bulk suppliers with low prices?

Home heatinghttp://www.dieselplace.com/forum/smileys/smiley2.gif

Does anyone have a big tank at home and refill the truck tank?

Yea that's the tube coming right out of the airbox.



<span style="text-decoration: underline;">http://www.uscom.com/%7Ehoot/cars/duramax/gmc/propane/fitting/images/DSCN3097.jpg</span>



I got my propane at a bulk supplier that sells it as motor fuel. Stop
by one of those lunch trucks and ask them where they get theirs. The
use lp to heat the food.



You can't refill from a home tank... I have a 500 gal in ground tank
that I couldn't use. Unless you have a pump. Liquid has to be pumped.



BTW: they make a killing selling barbeque tank-fulls.


Edited by: hoot

I have a 2400 gal and a 1000 gal tank. Each has a hand pump. You have to go directly to the lp suppliers to do any good on price. Look in the phonebook under 'gas', then call places that just sell lp. If you go to gas stations, U-haul, etc, they are just middlemen who buy from the suppliers. If you go with a tank at home, you need to own it to get the best price. If you contract with a supplier and they supply the tank, you can only be filled by them. If you own it, you can shop around. The next step after buying a big tank (at least 500 gal) is to shop for suppliers that will do a prebuy. This is where you buy in the summer, when it is usually cheaper than any other time. You pay for it, then they deliver when you need it. Some places won't offer prebuys. So even if you have a 500 gal tank, you can buy as much as you want and the price is locked in. As you can see, to get a price break you need to go through alot of fuel. As far as bbq bottles, you probably will get the best price at an lp supplier. If you already heat your house with lp, you can just put a pump on the tank to draw liquid, and pump directly into your tank. The outlet is usually capped, because home heating draws from the vapor outlet. You can also attempt to gravity feed fill, but it takes forever and you have to have some height difference between tanks.

I would go along with that milage (800-1000). I also agree, out of sight out of mind. The PowerShot is the one I recommend fully for easy of install, reliability and control of charge. Not to mention for big power (in combo) if that is your cup of tea.


Does this mean you can drive 800-1000 miles on one tank of diesel and 8 lbs of propane? Or that your propane will last you 800-1000 miles worth of driving (a few diesel fill ups necessary)?

A few fillups of #2 are necessary. I wish I could go 800-1000 on one tank of #2. Yes, the propane tank is a 8 pounder. The type that goes up under the frame in back. It replaces the spare tire.

gotcha,

for filling off of a home heating tank you don't need a pump or gravity it works by pressure difference of the tanks but as the home tank gets low the press will drop so it will take longer and as stated it already takes longer than if you have a pump. i think you would have a hard time getting a supplier to put a pump on a house tank.


btw where are you getting it for 1.09? i work for amerigas and employee price is 1.15 so you are getting a very good deal.Edited by: rocksam

Amerigas was selling around here for .99 a couple of weeks ago.


Other suppliers were 1.10 and now most are in the 1.20s.

I have a little grill bottle for now. Far from DOT legal, but for temporary dual purpose use it's fine. Some have reduced flow capacity gas valves though.


My intent is to get another forklift bottle. That way when the gas co. comes to fill our heating tanks I can have them top off the bottles, PLUS I'll have a spare for when my forklift runs out...

John your Forklift is tank is vapor draw?








Mac

FL tanks have both.

FL tanks have both.


Valves in place? I was told my tank(s) would need to be converted from liquid to vapor draw for use therefore I needed to buy a specific tank or revalve.


So at that point since I didn't have an unlimited supply of tanks I opted out.


Perhaps I was misled by my propane distributer.





Mac Edited by: Mackin

I remember looking at the fork lift tank at work. It had two draw valves. One labeled liquid and one vapor.

I get my LP from a co-op. It isn't $1.02 anymore, I can assure you. Regarding vapor or liquid outlets, all DOT approved tanks that I've seen have both. Keep an eye on Ebay, they have tanks all the time. If you are only using 5 gals or so for 1000 miles, vapor out is okay. If you use as much as I do, you must withdraw liquid, or you will frost the tank. Not a big deal in summer, other than having alot of sweat running off of it. In winter, you will lose all fuel pressure. When I took my first trip on LP with my Dmax, I had a vapor withdraw setup on it. I stopped at a rest area, and when I came back to the truck I saw something dripping out of the back of the truck. It was condensation from the tank running all the way out the back! The 30 gal tank was almost frosty.

I looked on ebay and saw 8 gallon steel forklift tanks for $130. It says they can be mounted vertical or horizontal. That beats the $375 for the other thanks I was looking at by a long shot. The question is can I use them? What question would I need to ask to find out? I don't have a forklift to go check.http://www.dieselplace.com/forum/smileys/smiley6.gif Do welding supplies fill propane tanks?

Tanks can not be mounted one way or the other. A vertical tank, must remain that, vertical. A horizontal tank, horizontal. Changing the orientation of a vapor tank, will make it feed liquid. Not what you want to do. If you have a vapor system, ideally it would be best if you had no liquid pickups on it at all. Most propane stores can block it off completely. Better to eliminate any possibility albeit slight for problems. Not to say you won't find a good deal on Ebay, just be sure you know what your getting.


Many people call horizontal tanks "forklif tanks" but most true forklift tanks use liquid propane only because they are running the lift/vehicle on propane and a greater amounts are required for that.Edited by: powershotone

Used propane tanks are not allowed to be shipped by standard means.

Some forklift tanks can be mounted both ways. The liquid tube is placed such that it goes to the bottom corner, so that if it is mounted vertically the tube is at the bottom, and if it is mounted horizontally it will still be at the bottom. The tank has a 'top' label on the side so that it is oriented properly when mounted horizontally. The vapor out is the same way. It has a tube that goes to the edge of the tank near the top so it will work in both directions.

So should I ask if they have both liquid and vapor, but at different locations?

Any tanks I've ever seen have the outlets labeled. It should say 'liquid' or 'vapor' or 'fill'. It should be easy to tell if you can see a picture. Also, if you get a forklift tank, get the bracket kit with quick release so that you don't have to unbolt anything to get the tank out.

John your Forklift is tank is vapor draw?








Mac








My forklift is liquid draw like many of the other LP kits out there. Mine is kinda odd in that my tank mounts vertically due to the lift being narrow and short.





My tank has both liquid and vapor ports.





Now where it gets interesting, is if there is any remote possibility that liquid can be sloshed into the vapor pickup with all of our harsh accelleration.





Manchester Tank would be best suited to answer this...

Even if you do get a slug of liquid into the vapor line, it will vaporize as it goes through the regulator and lines. I wouldn't worry about that, but if it worries you orient the tank so that the vapor outlet of the tank is towards the front of the truck. When you take off, the fuel will slosh the other way. It's interesting that with liquid withdrawal, the opposite happens. If the tank is low, and you corner hard or accelerate, sometimes you lose power because the liquid goes away from the pickup tube.

We used to fill fork lift tanks at the warehouse I worked at years ago with no pump. The small tank had a vent on it and would vent off gas allowing for a pressure differential. When liquid started coming from the vent you simply closed it off, didn't take very long at all so I don't believe that much gas was lost. If you had a vent on the tank like our fork lifts had I don't see why you couldn't refill your own bottles at home from a bulk tank as long as the bulk tank had a liquid draw source.

With a RV vapor tank, they are all 80% fill capacity now. This greatly reduces and almost eliminates the possibility of liquid getting picked up . Heavy accleration is the only kind there is isn't it?http://dieselplace.com/forum/smileys/smiley2.gif Certain model tanks also have baffles built in to even further reduce it but these are generally the longer (over 48") inch tanks. Mounted in the bed left to right, it is not a concern for any size tank. Generally, the 32 inch tank is the largest that can be under vehicle mounted. On an extended cab, the 10 x 23 is the largest.


If the tank has a liquid pickup tube as well, anything is possible, that is why we reccomend to have it plugged off completely. Turning it over may work for some applications, like a grill , but not for your truck. When dealing with your engine, don't scrimp on the tank. The wrong tank can cause undue problems and be costly in the long run.


With a Powershot, there are also several design safeguards in place. Propane vapor enters the system, through the lockoff valve, then through a pressure regulator, then through the Powershot itself, then it is delivered at atmospheric pressure through 20+ feet of hose, through the air intake and through the turbo, before it ever reaches the engine. In the unlikely event, even a small amount of liquid got through, it would be well vaporized before it ever reaches the engine.