Hi, been kind of lurking around here looking for ideas for the last year, and have seen some good ideas for my MH. I've decided that it's time to do some resto work on her, but I need some input on stripping weight out of her. There are a few obvious things like the running boards, but I was wondering if anyone knows what I can do to strip the body down to essentials without compromising safety.

Reason I'm doing this is I use her to live in when I work a thousand miles from home. I want to keep her liveable, but at the same time, try to lighten her up, and help her out with her gas mileage, as well as not making her little 351 work so hard.

Does anyone have any good ideas about putting her on a diet, without compromising safety? I appreciate any info anyone might have. Mechanical info would be cool too. I'm thinking about headers and dual exhaust, for example. Thanks.

 

Take the AC off the roof & leave the exhaust alone to save the $

 

I've given the roof AC some thought, and what I want to do is replace it with one that has a heat strip, for the dozen or so days a year that I need heat.. That will render the furnace useless, and I can take that out. Places where I work can get a little hot and muggy, so the roof AC needs to be kept.

As far as the dual exhaust, its my impression that headers and duals would not only help boost the mileage a bit, but also help give her a horsepower boost. She does struggle on long grades in places like the Appalachians. I'm not concerned about paying a few hundred bucks to do this, as it will probably pay for itself in a year, and anyway, I 'm pretty much going to redo her bumper-to-bumper over the next year or two, which is going to cost a few thousand.

Are you saying that dual exhaust and headers won't help the mileage? Even a mile or two on avg. will pay off eventually for me. I drive her every day for seven months, unlike most motor homes.

 

If you want better pulling power your best bet is changing the rear end ratio to a 4.11 or 4.56. You will loose top speed at a given RPM but if you also want better MPG you need to sacrifice MPH. Also buy some LTX M/S2 Michelins for better handling and MPG. Is this a B or C class?

 

It's a B. I'm not sure what rear end she has right now. I'm in the process of accumulating part #s and codes for research. Which reminds me. If anyone has a shop manual for her chassis, not a Chilton or Haynes, and wants to sell it, I'm all ears.

I keep her to no more than 60mph when I travel with her now, and mostly 55-60. I am getting about 13-15mpg when I do this, depending on conditions. I figure since she's an 89, she was basically designed and geared for the 55 speed limit anyway. I have run her at 65+ for hundred miles or so from time to time, and her mileage drops drastically to around 10, so 55-60 it is. Plus at higher speeds she labors, as there is no OD feature.

I run dry on long runs, no water in the tanks, leave work gear I don't need behind for a few days, etc. I know there is only so much I can do, but 50lbs. here and 30lbs. there will add up on the mileage per gallon. On short runs, I just use the front gas tank. Little things like that add up.

It goes without saying that fuel and maintenance are my biggest costs out on the road. I won't skimp on maintenance. If she needs something she gets it, because I don't like breakdowns 2000 miles from home. But if I can improve her mileage, even to 16-18mpg, I think it will save a substantial amount of money over time. I don't know if it's possible, but I don't mind spending some money to find out.

She's old but her drive train is all aces. I might beef up her suspension a little, which is another good reason to strip weight elsewhere. Most of the problems I have been working on are the electrical ones, mostly ground issues.

I can't afford a fancy new B+ unit or a sprinter but I can afford to make this old girl better. If nothing else, after I'm done with the resto/stripping work she should be a nice traveling vehicle.

Edit: the Michelins are a good idea. I don't need an off-road app or anything, but good heavy-duty all season radials, that can handle her 7000+ weight are ideal.

 

No Overdrive? Are you sure?

Your door post sticker and 5 minutes on the net will give you all the specs you need.

Even if you lost 1000# I doubt it would improve your MPG very much. Wind (speed) and rolling resistance are the 2 biggest robbers of MPG.

If you spent $4000 to go from 15 to 18 MPG you would need to drive 100,000 miles at $3.50 a gallon to break even. Is it worth it?

13-15 MPG on a class B is not bad.

 

Yep, no overdrive. I was surprised to find that out too. Apparently the OD fries out because of the weight of the vehicle, or they are actually worse for mileage somehow. That's what a couple of different people told me, and since I'm no expert on trannies, I take their word for it. It looks like the towing package was factory-installed, so that may be the reason.

You're probably right, I never will get the money completely back, I kinda like the old beast, so I figure a little modification and resto work might make her better. She's about a 6.5 on the condition scale so, I'm just gonna plow ahead and see what I can get done. I'm budgeting $3K for everything over the next two years, so the costs aren't too bad. I figure it's just beer money I'm spending, so WTH?

Thanks for the input from everybody. I hope I didn't sound argumentative. I'm just looking for different ideas for what to do with her.

Edit: You're also right about the 13-15mpg. It's damn good, as good as what any other B owner I've talked to is getting. Some of these new models still get only 10-11. You would think that after 20 years these companies could do better than they have when it comes to efficiency.

 

As far as 20 years and no better MPG all I can say is that the Laws of Physics don't change and the Laws of the EPA only get worse!

 

LOL...I hear ya! The roof is about to cave in on the whole RV biz once gas goes to $5 in a year or two. That's one of the reasons I'm searching for ideas.

Oh well, she's still cheaper than 7 months of hotel rooms and rental cars.

 

Unless you are in hilly country, or do jack rabbit starts and dime stops, stripping weight will not do much.

You have a huge frontal area (drag), and you are lugging a fair amount of weight (rolling resistance).

The best bet:

Keep everything in top tune.

Tires at highest allowed PSI for the weight, if there is a choice in fitment, narrower tires get better mileage.

Then keep speed low - 50mph to cut drag.

Real easy on accelerator.

Time your drives to coincide with green lights to minimize stops.

Drive on paved vs. unpaved roads (lower rolling resistance).

Beyond that.. carry limited amounts of water (weight) and dump holding tanks.

Then you are into mods that are $$$ like reengine...



Other tips... avoid gasohol... avoid fuel with ethanol (if possible, or get the least).

I am pushing 20mpg in a similar (regular not Class B) van.. but I am running diesel.

 

Gear that's good advice right there, he is getting not bad milage.

 

No problem. Do all that stuff already. Well, I do drive 55-60, but I'm not THAT **** about this. I'm still gonna knock some weight out of her just on GP, but other than that I can live with what I got.

Oh well, better get back to my regularly scheduled electrical problems. Anyone have a detailed dual tank schematic for this thing? I have an intermittent problem where it seems that my rear tank doesn't pump. It's weird, but I think the pump/sending unit setup inside the tank is going bad and I want to get that solved before I go back out on the road next month.

Thanks for all the info guys. It is much appreciated.

 

So is it an overdrive transmission? What tranny is in that thing?

 

I'll go get some numbers off her and look it up, but I know she's a 3-speed auto. She never shifts down at highway speed. I don't have a tach, but I would guess that 55mph is somewhere around 25-2800 rpm, just by the sound and feel. She doesn't labor at those speeds, but she's definitely working.

Give me a few minutes and I'll look up the particulars.

 

Glen check out RV.COM great site for RV info, that's all they talk about.