No Longer Own an Interstate

[SmokelessJoe]

I made my 1976 ARGOSY a Propane Free DIESEL POWERED trailer back in 2006 and have been enjoying the hydronic heating and diesel cooktop, plus the sophisticated LG Art Cool Split Unit air conditioning, ever since. So far as I know it may well be the Worlds’s First Diesel Powered Airstream trailer.



If you are interested in the build-out you can follow my thread here:

http://www.airforums.com/forums/f287...r-23048-7.html

It’s been a long time fascination for me to watch the dozens now of Sprinter upfitters and converters continuing to add propane systems to a diesel vehicle. Even Airstream, which supposedly prides itself on innovation, fails to exploit the opportunity to build a superior, ONE FUEL Interstate.

My God, I’ve been successfully running a Diesel TRAILER for 8 years now!

Now Roadtrek and a couple others in the Class B field have finally seen the light. Good.

There are no bold claims being made on the Roadtreck site about E-treck performance. It’s pretty wishy-washy stuff actually. So the first owners will unavoidably be the guinea pigs.

One of the short comings may prove to be the so-called Engine Mounted Generator.

In a more recent Forum thread you can see my own experience with a belt driven generator. Check posts #8 and # 14 in particular:

iwww.airforums.com/forums/f240/a-c-and-propane-120898.html#post1466537


As told there I was going to install a belt driven generator. Looking at the Mike Wendland video I see that Roadteck is using the same Power Mite generator that I bought - and eventually donated, unused, to be sold at a Mennonite auction.

I ordered my SPRINTER with the High Idle Function, a Power Take-off and the big 200 amp alternator, thinking I would install an engine driven generator and a big battery pack.

That proved impossible. I could not find anyone in North America, including emergency vehicle builders as far away as Florida, who could do it. Even when showed photos of such an installation supposedly done in the UK, they insisted there was no room in the motor compartment and I think they were right. It’s mighty crowed down there.

But the puzzle remained: why did Mercedes offer the power take off option?

When I bought the vehicle there was no Mercedes support like there is now. The selling dealership in Michigan didn't even know what the power take off or high idle function were for. They only knew the price on the option list.

(The current Mercedes engine room might be different from mine, of course).

The Power Mite is not advanced technology by any means; it’s old-hat 1960’s stuff. You will have the High Idle function in the Sprinter and you’ll need to run the truck motor at a constant 2200 rpm to make current. You will also have an old fashioned choke -like knob and cable connection to engage the Power Mite when you want to make electricity.

The Sprinter is very quiet at regular idle but not when revved up to 2200 rpm. It’s NOISEY, louder than many inverter technology generators are nowadays.

In the end I didn’t feel it was a sensible idea to start with. Noise. Wear on the engine. Running a 5 cylinder engine to make 110v current to charge batteries. It all seemed wasteful to me.

There must surely be a better idea than the Power Mite out there, somewhere.

I am going to be very interested to see what happens as real builders adopt some of my renovation ideas. So far, I feel pleased and vindicated.

[Bikerbill]

Well first it doesn't make sense to operate an engine mounted generator to make 115 volts only to down covert it to battery voltage which BTW is 24 volts on the Roadtrek E-trek. Why 24 volt you probably ask. Because inverter manufacturers need 24 volts once you hit like 4000 watt inverters and above. In fact some of the 10,000 watt inverters need 48 volts. RT does it by using 6 - 8 volt AGM batteries. And to the best of my knowledge they do not operate their engines at 2200 rpm. What they do is once you decide to recharge your batteries with the engine you merely start the diesel, blip the gas pedal once to rev it up to about 2200 rpm and then take your foot off the gas. The 24 volt generator that fits quite well on the engine PTO bracket is a one wire field generator that will then begin to produce about 3000+ watts @ 24 volts at IDLE and if you are driving the vehicle it could approach 5500 watts at highway speeds.

As far as cooking, no diesel cooktop. Instead an induction electric cooktop either recessed into the countertop or as we are having built, it will be a portable induction cooktop so we can place it outside in the camping area to cook outside if my wife wants to.

Yes there have been many stories running rampant since last spring of 2013 when it was first announced about the RT E-trek. I hesitated last fall on buying one and bought my Airstream but last week traded it on a 2015/14 Roadtrek CS Adventurous E-trek with Webasto diesel heat and hot water. I will have to wait probably 8 week now to get it as Webasto is getting scarce because of demand. But I think the wait is worth it.

Oh and did I fail to mention, RT is so convinced that the E-trek gets a 6 year full warranty from RT (not the Mercedes portion). Everything that RT installs is covered for 6 years, not prorated. Batteries, water pump, fridge, TV, stereo, generator, inverter, AC. Basically if they installed it, its covered for 6 years. They must be pretty confident about their product.

[Dungrace]

Biker Bill, do you mind letting me know how much you paid for your Roadtrek and which options did you get? I am thinking of getting rid of my 2014.5 Interstate ext after I get it out of the shop. Thanks!

[Titus]

I looked long and hard at the E-Trek before buying the AI EXT. In the end there were just too many new things on it, some of which didn't add up. The 8 batteries are 8 6V batteries, which ends up only being a 4X increase from the AI. And 240 W solar would do a worse job of charging them than does 100W at charging the 2 in the AI. Engine driven 3600W generator sounds good, but that many AGM's take about 1 hour to bulk charge then 2 hours on absorption, and idling 3 hours didn't sound quite so good. And I didn't see how the A/C could possible last 9 hours on batteries.

The one plus that did make a lot of sense was the Webasto diesel-fuelled coach heater and water heater.

None of the RT dealers had any experience with the E Trek and couldn't answer my questions - even if they had wanted to. Would like to hear your real experience on the above issues.

[Bikerbill]

Our Roadtrek on order is a 21015 RT build on a 2014 Mercedes 3500 dual wheel Extended body chassis. Silver in color. E-trek package which includes 240 watt solar panel, total of 8 AGM 6 v batteries, engine generator, 5000 watt inverter, 6 year warranty; Mercedes Luxury Package which adds all the fancy MB options; power awning (but still has arms); the CS Adventurous model which includes 7 cu ft fridge/freezer with m-wave above it, power sofa; screens for rear door only; leather on power sofa; 22" flat screen on bracket; 4 chrome-2 steel wheels; silver paint; extended length body; shipping. The factory list on this is $150,278 since we placed the basic order we dropped the Alde propane radiant hot water+domestic hot water instead installing the Webasto diesel hot air+domestic hot water for an additional $700.

You can price this out from the RT webpage except the Webasto which is a special order. Dealers will sometimes discount up to 20% w/out a trade but I had my 2014/13 Airstream w 3 capt. chars and the long & short wardrobe and less than 8000 miles in 10 months.

My dealer is Fretz RV in Souderton, PA a long-time RT dealer. They are listing my trade in at I believe $107,400 last time I looked on their webpage. A big reason I rushed at this time was the NADA book will come out with new trade in values Aug 1st and we know my unit will drop in value. I had talked with Colonial RV, NJ as he is the dealer who sold me the Interstate and he is also a RT dealer but his trade was much lower.

If you have read my postings in this particular run on the Forum you will read of the differences I have noted that I do know of or will expect. The biggest is in the cabinetry I feel is not of the Aristream quality. I don't know where you are located but at the upcoming Hershey RV Show, Hershey, PA in Sept. it is expected that RT will debut its new TS model-Travel Series. From the pre-release pictures it looks a lot like the Interstate inside. 4 capts. chairs, laminate cabinetry, aluminum extrusions, etc. Not sure what E-trek kind of options may be available when it debuts. You might want to look at Facebook for "Roadtreking: The Group"; also on FB,, "Mike Wendland", other pages www.classbforums.com; www.roadtreking.com; roadtreking.com • roadtreking.com. Follow them, especially the Facebook and you will learn much, as I did.

[SmokelessJoe]

Bill,

The generator that I saw in the Wendland video looked exactly like the Power Mite that I bought for my failed experiment and I made the mistake of assuming that it was, without knowing for sure.

There aren’t many specs on the Roadteck site, probably for the good reason that they wisely want to keep information away from their competitors.

If the system works the way you think it is set up to work it should be OK. The way that I was going to do it would have been unacceptable in the end.

Make sure you keep your old forum posted on your experience with the Roadteck.

Induction cooking is a great way to go. I have a portable one that I use, sometimes outside, sometimes in, sometimes with the Webasto diesel cooktop, sometimes instead of.

The heat for my hydronic system comes from a Webasto TSL 17.

The point that I really wanted to make was that it takes a long time for new, better ideas to creep into the conservative till now RV world. The Airstream INTERSTATE, which we Airstream types like to think is state of the art, continues to use propane when ONE FUEL, diesel, is so obvious.

There were some detractors here when I first mused about better ways to do things so I am glad to see ideas I once built out now starting to be used by others.

[Protagonist]

Originally Posted by SmokelessJoe

The point that I really wanted to make was that it takes a long time for new, better ideas to creep into the conservative till now RV world. The Airstream INTERSTATE, which we Airstream types like to think is state of the art, continues to use propane when ONE FUEL, diesel, is so obvious.

To each his own. The yachting world has long offered diesel appliances, including stoves/ovens and water heaters. Yet even there, propane remains the fuel of choice for just about everything except spinning the propeller.

The biggest short-term drawback I see with the e-Trek is that someone who is out boondocking will drive to their campground, forget to refuel right before parking, and then drain their diesel tank keeping all of their appliances properly electrified, only to discover they're stranded in the boonies because they ran out of diesel before they drove home.

Even the old Airstream motorhomes with a built-in diesel generator in addition to the main engine had a separate fuel pickup that would have the generator start sucking air when the diesel tank was still at least 1/3 full, so there was always 1/3 of a tank left for driving away. You couldn't strand yourself by using all of your fuel for generating electricity. When you use the main engine to generate your electricity, you don't have that separate fuel pickup in the tank, and it does become possible for an inattentive user to drain their tank while generating electricity.

[Lily&Me]

Good points, Protag!

We need the clarity of minds like yours here.



Maggie

[Bikerbill]

I'll repeat what I posted in one message above. Take time to monitor Facebook "Roadtreking: The Group" and follow Mike Wendland. He's got #1 E-trek and is in Memphis right now boon docking with the AC on last night. Per his post and then he got up in the AM and ran the engine for 20 minutes.

There are plenty of naysayers out there with all sorts of statements of engineering and data lists and rules that say the E-trek can't work. Well I've chatted for about 6 months with several owners that say they do work. But you have to know how the system operates. Drive them, run the engine, ,park them in sunlight or plug them in when parked. And best of all they have a 6 year warranty which covers the electrical system designed by Roadtrek. And yes, I've been quizzing the engineer who designed the E-trek system. He's given me some answers to my questions, but not all of them. We've discussed it and when I ask him a question I allow him the option of not answering if I am asking proprietary information or as I call it, the "secret sauce." Once I have mine in my possession he knows I will open compartments and look and take pictures and ask more questions. That's how I learned about my Interstate. Lots of pictures and questions to the factory and a log that I have with the Q+A.

As far as people coming to a campground with low fuel and then running out at the campground or wherever they are parked due to running the engine. You'd be driving into the parking lot with the "low fuel" light on so I say forewarned is forearmed. For many years I have followed many forums/blogs for motorhomes: diesel, country coach, bus and now airstream and roadtrek to mention a few. I have always found it quite interesting and many times amusing to read questions from people who have no idea of what they bought or how it works. Its all too easy to "ask" the questions on a blog rather than read the instructions. I have always been a firm believer of RTFM. Once you read the manual and you still have questions, go for it on a blog.

Last summer when I sold my custom built 15 year old Prevost bus, the buyer was a surgeon form San Diego. I asked him what his past m-home experience was. His answer was, "I think I owned a 35' Winnebago or something over 20 years ago." We discussed when he comes to pick it up in PA to give me about 6+ hours to go over and explain all the systems, etc. I told him that it includes all the manuals, etc. He showed up on the appointed morning and said he had to fly back home later than day. Could I cover everything in 2 hours. He and his friend listened as I spoke as quickly as I could and after 2 hours they drove away with it only to park it in the long-term parking lot at Phila airport. His friend flew back a few weeks later and on his way home with it called me from North Carolina that the engine had stopped on an off ramp. My first question was "How's the fuel or did you fill the tank after you left my home?" I'll let you guess what was wrong!

So yes, owning an E-trek requires some thought process and obviously its not for everyone. And maybe some common sense also, which I think is missing in many RV owners, be it a travel trailer, motorhome or custom built bus.

I too am always learning and just a few minutes ago read a post on Facebook that I never gave much thought to. When pulling up to a gasoline pump (not diesel) just turning off the propane tank is not ample safety. You need to make sure the 3 way fridge and water heaters are electrically powered off since they COULD attempt to light with the spark ignition even though the gas is off. Best way to insure that is with the main electrical switch turned off while fueling. Now I must admit, until we bought the Interstate some 10 months ago, I had nothing propane in my prior motorhomes for over 20 years so it wasn't on my radar. And I won't have any propane in my E-trek, but the message will stick in my mind for the future.

[Lily&Me]

Just to be clear, I wasn't diss'ing you, your informatioin or your new rig.

Just acknowledging and appreciating the perspective some of the more analytical and technical minds give here.

It's a good thing, for all of us who simply don't think that way.

I wish you many miles of happy travel. May it be everything you hope for.



Maggie

[Protagonist]

Originally Posted by Bikerbill

I'll repeat what I posted in one message above. Take time to monitor Facebook "Roadtreking: The Group" and follow Mike Wendland. He's got #1 E-trek and is in Memphis right now boon docking with the AC on last night. Per his post and then he got up in the AM and ran the engine for 20 minutes.

I'll repeat what I started my last post with: To each his own. Buying an e-Trek may be the right move for you. It won't be the right move for everybody.

I'm happy that you found something that better fits your requirements. I hope you get many enjoyable years of use out of it.

Don't take our speculation of possible drawbacks as a criticism of your decision; it's not. You don't have to waste one single minute justifying your choice to us or anyone else, except maybe your own family.

My Interest in the eTrek is purely academic; as an engineer I find any new technology to be fascinating. Doesn't mean I'l ever buy one.

In fact, I'll probably never buy another RV of any kind, ever again. Not even a newer Interstate. The one I have is fully paid for, and I'm about ready to retire. My retirement budget doesn't allow adequate discretionary funds for buying a replacement RV, ever. Unless I want to give up camping to pay for the new RV, which would be silly.

Since my 2012 Interstate is likely to last at least as long as I'm physically and mentally capable of using it, the one I have will just have to be good enough for me, no matter what new and improved RVs hit showroom floors later.

[avanti]

I am kind of a moderate on the propane issue. On the one hand, our new GWV Legend has the Espar diesel heat and on-demand hot water, and a NovaKool DC-only compressor refrigerator. I absolutely love this lack of dependence on propane. So, the only remaining propane-consuming devices are the cooktop and the genset. We looked hard at the possibility of specifying a diesel genset and deleting the propane entirely, but decided that it just wasn't worth the extra size and expense. The cost of a propane system is not high; the systems are mature, simple, and reliable; a tank full of propane is going to last us a long time -- so why not?

As for safety, neither of our remaining devices have automatic igniters. I also specified a convenient, indoors switch to disable the propane (it will be "off" most of the time).

I like the "all electric" approach in principle, but not enough to be a pioneer. I will be watching the experiences of the early adopters with interest. Please keep the reports coming, Bill.

[Boxster1971]

Bill,
Saw that you have received your new Roadtrek over on Facebook. Looking forward to hearing your comparisons. I like my Interstate now that I've added many modifications, but I'm always interested what owners of the Roadtrek E-Trek think of that system. I'm also following Advanced RV as I was going that direction once, but they just were not ready to deliver when I was ready to buy.

I've now got 45,000 mile on my Interstate in less than two years of traveling. All the kinks are out of my unit - now I'm just wearing it out. At this rate I'll be ready for a new B-van in a few years.

Cheers,

[Option7]

I have a 2007 Interstate with the 2.5kw propane generator. You can't hold a conversation or try to sleep with the generator running since it is way too loud. You can run the engine but you can burn $30 to $40 per day in Diesel.
I immediately added a 110W solar panel and two golf cart Lifeline batteries. You use reduce the loads in the coach to take advantage of solar so I also converted all the lighting in the coach to LEDs which reduced the lighting load from 34 amps @ 12VDC to less than 2 amps! I also replaced the propane sensor with a high efficiency unit that uses 46 mA instead of the original 76 mA. I also use my fantastic vent to automatically vent the coach whenever the temp inside gets higher than 85 degrees which is fine during daylight (solar charging) but you need to manage the load after the solar panel drops below 1 Amp output.
I can dry camp with the fan (on low), my 22" TV and my sound system for 6+ hours each night for a week without plugging in.
I installed the 2 golf cart AGM batteries under one of the dinette seats.
I only use the generator to run the microwave, toaster oven or espresso machine so the small propane tank can be used primarily for the refrigerator, hot water heater and cooktop burners.
This allows me to do far more than any Roadtrek or newer Airstream Interstate and it only cost me about $2500 to modify/add these new features which extend the life of the coach by reducing thermal cycling from day to night which beats up the interior materials, appliances, electronics, seals, etc.
I save at least $50/day in Diesel fuel and propane to dry camp with my solar/LED conversion. I've got over 90K miles on my unit since 11/07 and saved at least $3500 in diesel and propane over the past 6 years using the coach about 6-8 days/nights per month.

[Bikerbill]

OK so here is my first comparison between our Airstream Interstate and the Roadtrek CS we just had delivered. Keep in mind, we drove it home and have not been away with it. Please take time to read the comments at the bottom of the attachment.

We had considered last spring and into early summer to make mods to our Airstream: install much larger solar, add more batteries and a bigger inverter, improve the inverter control panel and add auto-start for the benny, improve the bathroom door into a double door and some other minor issues.

But we would still have a Suburban propane furnace which I quickly disliked. And the propane genny running underneath.

I estimated these costs of materials, time and labor vs the cost to trade in and we decided that this year was the year to do it. So we did.

As Protag said, to each their own. I'm not "dissing" the AI but merely providing what we found to be similarities and differences.

[UKDUDE]

Originally Posted by Bikerbill

OK so here is my first comparison between our Airstream Interstate and the Roadtrek CS we just had delivered. Keep in mind, we drove it home and have not been away with it. Please take time to read the comments at the bottom of the attachment.

We had considered last spring and into early summer to make mods to our Airstream: install much larger solar, add more batteries and a bigger inverter, improve the inverter control panel and add auto-start for the benny, improve the bathroom door into a double door and some other minor issues.

But we would still have a Suburban propane furnace which I quickly disliked. And the propane genny running underneath.

I estimated these costs of materials, time and labor vs the cost to trade in and we decided that this year was the year to do it. So we did.

As Protag said, to each their own. I'm not "dissing" the AI but merely providing what we found to be similarities and differences.

Very interesting comparison Bill, and I hope you'll continue to keep us in the loop on your thoughts after you've had a chance to use the CS.
Coincidentaly, on the Sprinter-Source forum another new owner has written up his thoughts on ownership of a CS Adventurous after 4 months of use. He also has the E-Trek package and is essentially saying RT's claims for it are misleading.
2014 Roadtrek CS Adventurous - after 4500 Miles - Sprinter-Forum

[Ron_CA]

Thanks for the write up Bill. Appreciate you taking the time.

Keep in mind that you were comparing the old chassis vs new chassis on the Roadtrek. Some of the thumbs up on RT have already been improved by Airstream. While I like some of what RT has done, I am happy with my decision to go AI.

Probably the biggest deal breaker for me was size of the black tank.

[Boxster1971]

Thanks Bill - appreciate the detailed write-up. Since I added 400 watts of solar to my Interstate it's nearly perfect for my use. It is nice to know that Roadtrek has finally adapted the long Sprinter chassis. With over 45,000 miles on my 2013 in less than two years I could be in the market for a replacement in a few years.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[73shark]

Thanks for the detailed write-up.

One deal killer for me would be the smaller A/C unit since I use mine primarily for hauling grandkids on vacation and it gets warm back there even with the rear A/C on whenever the ambient goes over 90*.

[73shark]

Any updates after a couple of months of experience?
Edit: nevermind, I see you've already done it on another thread.