My first sign of trouble could be that the poll doesn't even go down to 8, just "10 or below."

I just took a 2,500 mile trip in my '97 31' Fleetwood Class C RV, built on an E-Superduty cab with a V-10. It currently has 103,000 miles on it. I averaged 7.7 mpg throughout the trip, doing 63 mph almost the whole time.

Is there anything I can do to improve gas mileage? I bought the RV used with 90,000 miles on it, and judging by what I've found since I've tore into it, it hasn't had the plugs or timing belt changed yet. I've done all the other regular maintenance on the vehicle.

I talked to another RV owner who has a 2004 31' Class A RV with a V-10 and he said he gets 14 mpg. I have got to be doing something wrong.

Would new plugs and timing belt make that much of difference in gas mileage? Is there anything else I can do to the engine to improve gas mileage that would be worth the expense?

At $2.00 a gallon, and 8 mpg currently, it won't take long to pay off any investment in the engine if it just improves the mileage to 10-11 mpg let alone 13-14.

Edit: I should add that GVW is about 13,000 lbs loaded for travel.

 

Well there is no timing belt...so LOOK I just saved you hundreds of $$!!

I would first make sure the engine and tranny are in a perfect state of tune. Meaning: new (proper) fluids everywhere, new plugs, new filters etc. etc.

I'd make sure you are runnning max tire inflation pressures and that the brakes are not dragging or anything.

I'd lube the chassis.

I'd also have you realize that your buddy may be full of crap. 14mpg in a loaded class-A sounds like a pipe dream...or he's been hitting the pipe. Heck, just look at the average MPG for the pickup trucks in the survey!

Also realize that your V10 produces less power than his 2004 V10. So you may have to step on the go-pedal more.

So...first things first...make sure is is running PERFECT. THEN test the mileage...see if that helps....if not then we'll all dig in to see what we can do to help.

 

Thanks for the info. No timing belt, eh? Hmph, that does save some money then.

Ok, all fluids and filters have been changed regularly since I bought it, including the tranny. I still need to have the chassis lubed. I replaced the shocks and steering stabizer and all 6 tires have been replaced and balanced and air pressure is maxed out. Pretty much everything that is standard maintenance has been done except the plugs. I haven't changed the O2 sensor, but don't know enough about them to change them before the code pops that something is wrong with it.

Now, about the plugs, I have them on hand (Autolite double platinums - any suggestions on gap?) but haven't changed them because I can't find where they go. I've looked in from the front and the rear of the engine and just don't see them. I assume I need to remove the upper and possibly lower intake to get to them. Is that correct?

I knew there was a reason I keep hanging onto my 78 F-150.

 

I have a 2005 f350 drw 4x4 with a flatbed dump and weigh 10000lbs empty and I averaged 8.2 mpg last tax year '04 with putting on 13000 miles. Just thought this might make you feel better!

 

Cool. I just thought with all the people in the V-10 gas mileage poll getting 14, 15 or more mpg, I HAD to be doing something wrong.

 

Yup, you gotta look at what you weigh compared to the empty SD's...

Fill up your tires.
Keep your foot out of it.

Can't think of anything else right now

 

I doubt if you are going to improve it very much. They folks who say they're getting 13-14 pushing that much wind are blowing smoke. Are you sure the torque converter is locking up? I have an '05 E450 that grosses about 18,000 lbs with towed and I get slightly better than your 8mpg and I drive for economy. I have not figured mileage since last trip but I believe it is getting broken in at >8K miles and the mileage may be improving.

ray

 

stong suggestion here take those plugs back and get the standard single factory platinums. the doubles are nice but tend to start miss fireing from the voltage drop across the double tips.
in my 42 years working in dealers and truck shops i personally have found the standard factory plug is always the best bet.
also when you change them you have the early type heads with the 5 thread count plugs. get a air compresser blow out around the plugs before you pull them. also change the plug boots "a napa type part" they don't cost very much. when you put them back in apply never seize to the thread and use a inch pound torqe wrench. not the old they feel ok .or you can pull the threads out or blow a plug down the road.

 

I have a 2004 Dutchman Express 28a with a V10. I have an average of 8.0 mpg. This is for over 8000 miles.

 

Dutchman
welcome aboard and into our bseg club. sounds like you have a nice rv. good luck with it.

 

Welcome Rv'ers!

Comparing the economy of your heavy home-on-wheels to the MPG of our empty pickups is doing yourself no favors. Besides carrying twice the weight, you have twice the aero profile (wind resistance). IMO 8 MPG is quite acceptable for your vehicle.

 

well we have 15 f 550 trucks on our fleet which weigh in at about 19,000 GCWR every day. they get 7-8 mpg. however they were using bulk 10w30 in all of them since new and have since switched to bulk chevron 5w20 and have picked up .5-.8 a gallon in each truck. the company account says it costs 23.00 less per truck per week for a total fleet savings of 6,900.00 a month.

 

wow, all good info. Thanks.

 

I get 7 sometimes 7.5 when I tow my TT. It may have the same wind drag as you because the slideouts tend to make the trailer higher that one without a slide. Probably weigh about 16K ready to camp. Empty and not towing, I get 10.6. The best I ever got was 12 and that was a good chunk of highway driving on that tank.
I'd say you're doing OK.

 

You may get a little better during the summer when the "winter" fuel blends go away. I see a 10% drop on winter fuel.

My friend has a 34 footer with a V-10 and gets between 8-9 on the road. You are doing fine...