GM deserves some credit.I just returned from a 3000 mile trip-NOLA-Flagstaff-NOLA in a 202,300 mile 1998 Suburban 2wd.It delivered 21.3 mpg at 70 mpg CC on the whole time-45 psi well worn tires,Mobil I 5w30. It has the older, less efficient 5.7 liter motor.The 5.3 is more efficient.I had no idea that an ancient Suburban could get 21.3 mpg at 70 mph.It is rated 12/17-current ones are rated 14/20.
In pure city driving it gets 14 mpg with hypermiling lite techniques.It could get 17 mpg if I shut off at redlights.
The Volt will save GM, but their 1/2 ton vehicles are very good.They will sell in much lower volumes, but they will still be needed-work/fleet/farmers/contractors/cops/gov etc.Folks ought to "car share" them like they do with some cars.

Charlie
PS I have a Prius also.It would have gotten about 45 mpg same speed, but with a much smaller load-no mattress of pillows,or 2 ice chests,MTB,tools etc.

GM historically has done a great job of gearing their cars to get good gas mileage on the highway. I've had 2 full sized Buick/Oldsmobile with the 3800 V/6 that got 32-35 mpg consistently and a couple of Cadillacs with the 4.9L V/8 that got 28-29 mpg consistently. At 55 mph they were just above idle and at 70 mph right around 2500 rpms.

Hi Charlie,

I made a few edits in my copy of your posting so please make sure I didn't make any mistakes:
It is in the right place, now, but please avoid duplicate postings of the same message, shotgunning. Just to remind folks, "Anything goes" means wide open subjects except sales stuff and what is banned (aka., personal attacks SPAM.) "Marketing" is where sales stuff goes but it needs to be applicable to hybrids. But this was a very timely posting for my family.

Every year my wife has had one birthday request, "An RV," and every year I've had to offer her something else. It has been and remains my hope that the GM two-mode or a high-end HSD would show up in RV frames ... a win-win considering the glut of RVs waiting for customers. But this year, I spied a '93 Coachman, Class B, built on a GMC "G van" body (Ebay: 300221600629) and knew I could do it. So Saturday morning, I left at 3:00 AM to go pick it up and at 3:10 AM Sunday morning, I parked it in our driveway:


I just woke up from my nap and have chores to do but later, I will follow-up with more details. However, even this '93 has anti-lock brakes and O_{2} trim adjusted emission controls. I had already started some Prius-RV towing development but these experiments are not ready for 'prime time' until my testing is done. Still, this was a timely posting and we're going to have fun.

BTW, this vehicle has a rear-wheel drive so I will be looking at the drive-shaft inserted electric motor. Also, I have some extreme 'flex fuel' ideas.

Don't be a stranger Charlie. We're going to open some eyes including how to safely, flat tow a Prius ...

Hummmm, both vehicles have 2" receivers ...

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

caholla,Bob,
Thanks for the response. Gm no doubt knows how to gear its V-8s, but the gearing-I have the tallest rear end-the 3.42- really isn't very tall.It turned about 2000 RPMs at 70 miles per hour-almost exactly what our former trip vehicle-a Pilot-turned with the 3.5 V-6 and 5 speed auto trans.One difference I did note was that it NEVER,I MEANS NEVER downshifted when climbing hills.The Pilot would always downshift for the most gentle hill. The 4 speed GM never downshifted despite the cruise control being "on"

Another difference,it-the trans- never even seemed to Unlock when climbing at 70 miles per hour in CC.Normally,you can see a vehicle suddenly gain a couple hundred RPMs if it stays in top gear but "senses" an increased load. It would never vary a bit from the 2000 RPMs except when going downhill when they would drop a bit.

Bob, I eyeballed conversion vans,and some raised top conversion vans.I stayed with the Chevys because you can buy a NEW-NEW-Goodwrench motor for my 5.7 for $2400 delivered and a new trans for $1700 delivered!! Your motor is the 5.7 also, but the slightly earlier TBI equipped motor.You can get them even cheaper-maybe just $2000 or so.
I noticed that the NEW revised EPA specs for the Suburbans are essentially the same as for the box type 1500 vans.Your van must be a 2500, but essentially the same-heavier duty suspension maybe few hundred more lbs-but roughly the same.

Via my well calibrated eyeball it looks like the top adds about 6x1.5=9 sq FTfeet to the 6X 5.5~33 SQ FT VAN.Maybe the CD was .4 so your effective frontal area was maybe 14 sq ft? The "top" looks clean-maybe .5 CD- so maybe it increases the effective frontal area by 33%.

I'm guessing out of the box you would get about 10-14 mpg at 65 miles per hour-no mods,petro based oil and lube ,standard tire pressure and newish tires.Huge range,I know.I could see you eventually approaching 20 mpg
A scangauge won't read from a 93 will it? What sort of info is the vehicles "computer" getting? Can you access it? Any idea what mpg gets at a steady highway speed??

13-14 mpg is pretty decent for something soooo comfortable.We rough it sleeping in back at rest stops in TX.It isn't really tough since we have about 98"x50" with the 3rd seat removed,and the second folded flat.We use a futon mattress and our own "home" pillows, but we will go to a thicker mattress next time.Your wife is right-there is no substitute for sleeping comfortably while traveling.

The PAN is Polyarteritis Nodosa a very obscure fairly rare autoimmune disease that attacks her arteries.In her case it has been confined to arteries supplying nerves.She had a very rough time for many months, but is doing pretty now on potent immunosuppressing drugs.If she stays in one position too long it isn't good,so plenty of room to move around is essential.Using the Prius was out.

I'm very curious what sort of numbers-and mods-you will get/do-.They-big GMs have lots of potential,and they ARE DIRT CHEAP NOW!
Any plans for AT fluid-I know you went to different fluid in your Prius "gearbox"?

Thanks,
Charlie
PS Even more big windmills off I-40.Before they were just in Weatherford OK.Now they are west of Amarillo not far from NM.Plenty off I-10 outside El Paso. TX and OK are just perfect for wind farming.

PPS With your tinkering/fine tuning and reasonable speed-say 60 miles per hour-I could see your RV approaching 18-20 mpg.

Bob,
Just read your PM;you drove it home from Fla. so you already have some MPG numbers.Something like 10-12 mpg on a 65 mph trip maybe? I don't think there are EPA numbers on one tons like that, but the 1500 probably have revised numbers-maybe 12/15 ?

It is huge compared to the Prius! It must weigh-fueled but with no humans or load-maybe 7500 lbs or more?

It has an onboard generator? You could probably run lights/tv,fridge with your Prius Generator.It puts out~1000 watts or so. With an onboard gen. you can just pull into a rest stop crank it up,and get a decent nights sleep.

Does it have the 5.7.I guess it could have the 454-7.4 liter) or 502? It is heavy,so it wouldn't be over engined with the Big Blocks.

I'm really curious what you will do with it.

Nothing beats comfort when traveling,and size equals comfort.Motel rooms-La Quinta-are about $140/night in season.You can save some money, have some fun.
Luck,
Charlie

Hi Charlie,

First order of business is an engine tune-up and fixing the latent problems that need to be addressed. This was as expected and I'm just happy the RV made the 600 mile trip. I think the bulk of the problems came because it had been sitting unused for a long time. My last leg at 60 mph gave 16 MPG and I suspect it was just the act of getting all of the systems up to operating temperature did half of it.

Regardless, the RV is in a good home and I feel comfortable with not only the repairs but also some of the enhancements. Most of all, if it gets my wife out of the house and enjoying life, it will be worth every cent. She has arthritis, fibromyalgia and a chronic back problem. So I know what it means when your woman lives in pain.

Well nap time, chat at you later.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

16 mpg-that is pretty spectacular for a vehicle with maybe 35% more frontal area than my Suburban and probably lower differential(3.78 or 4.1). When you factor in ancient spark plugs, old distributor/rotor or equivalent,same story on the wires.No doubt the old is gooey old petro based oil,and maybe the tire pressure is a bit low-Ancient trans fluid diff lube.

Probably doesn't make sense to start "breaking things" but that roof AC has a fair amount of frontal area. If you have an onboard generator one of the cheapo 5000 BTU window units-all have at least 9.7 EERS now,and some were 11+ might save some drag.More work than it is worth probably, but someday it might be...You could just quick install the window unit when you park.See how quickly I "break" other folk's stuff! 16 MPG right out of the box probably best to leave the aero stuff alone.Someone did a good job on the aero qualities of the upper addition.

Yes, chronic pain is very bad.Karen uses Lyrica because of the strange pain/paresthesias in her legs that is the result of nerve damage.The Lyrica is a mixed blessing, but better than nothing.She loves to go to Flagstaff,and the Suburban is much better than the Prius or the Pilot-big is good on long trips.Your RV is much more comfortable-a real bed with your own pillows is nice after a long day.Folks with chronic back/neck pain usually have their own pillows broken in just "so."

I replaced the radiator/waterpump/belt tensioner/brake booster for just $400-all new parts except the rebuilt brake booster.Lotta GM new parts-delco and aftermarket out there.

GM made/makes surprisingly efficient drivetrains-pleasant surprise to me.My 1998 is pretty quiet on the highway-close to 2003 Honda Pilot noise levels. I wonder if your van has a big blanket like noise absorber glued to the underside of the hood?
Thanks

Charlie
PS I checked the auction-great deal $5k! The miles don't seem to be a big deal with the GM drivetrains. Mine was at 195,000 when I bought it.I used 24 ounces of 5w30 Mobil I over the 3300 total miles of the trip.Mobil I makes a 10w30 HIGH MILEAGE oil, but the 5W30 should give better mpg-with the tiny bit of consumption being the penalty.
Worse case you can buy a new GM motor for $2200 delivered-Pace and others sell them online.A new 4l60E or the 4l80E is about $1700 -New-delivered. Hard to beat $4000 for a new motor and trans.Doubt you'll need a new motor-they seem to last forever.Folks with RVs generally maintain them pretty well-giving them a good once over-oil,trans,diff lube once or twice a year before the long trip they are bought for.
You have me looking for a GM conversion van-poors mans RV!