18 mpg Dodge while towing?

I word with someone that claimed his Tahoe MPG average didn't change much when he towed and he was sure he got 18 when towing. Towing 100 miles won't change the average much if you have 100,000 miles and never hit reset.

My stock 2010 F150 pulling my 4000lbs loaded off-road POPUP trailer will make my 429 mile trip from King George VA to Gatlinburg TN on one tank of gas. This is a totally different situation however with almost ZERO wind load from the POPUP trailer. Actually when we go without the trailer we almost do the same thing haha...

I will Gas up when we hit NEWPORT TN and head on in to ELKMONT CAMP in the Smoky Mtn Natl Park. Run around town for three to four days and use maybe a half a tank. Then Gas up again at Newport TN for the return trip back to King George... Thats in the 19-21 MPG I'm guessing - Never really calculated it...

When my son-in-law follows us down with his older 2004 Dodge Truck pulling about the same weight with his high wall POPUP trailer doesn't do as good as my F150 does.

Roy Ken

I'm not saying he is getting 18, but the 2002 and 2003 were noted as being the best for fuel mileage on the Cummins. Add to that that he has a stick shift and. Does 55, it could be pretty good. When we did the upper peninsula trip this past summer one of the guys we were with was getting poor mileage on his mh with a 440,dodge, so we slowed down to 55. Wow! What a difference. My mileage went from my normal 10 mpg, to near 13. That is a huge difference. Now the question is, when I'm on my own can I travel that speed for hours? Probably not, but speed does kill the mileage.

azdryheat wrote:
Friend claims 18 mpg while towing 35' toy hauler with 2003 Dodge Cummins Diesel with manual transmission. He says he never goes over 55 mph. Is he for real?

I have a same '03 Dodge/Cummins NV5600 305/555 HO 3.73 axle 2wd in a 2500 short bed quad cab truck.

19 mpg while towing a heavy TH ???
...could be a single best tank using the short fill method.
....... watching the fuel guage and guessing at mpgs.

A '03/'04 305/555 Cummins HO does get some of the higher mpgs. Mine has averaged 12-12.5 mpg (pencil figures) over several tanks on long trips pulling my 11000+ lb 5th wheel trailer.

I've never calculated the MPG I get towing my 15,000lb 5th wheel but I'm sure it's near 20 MPG....why is my nose growing???

I know as soon as I installed a tuner on my Ford the electronic gauge was thrown off. Always said I was getting way better mileage than I was.

azdryheat wrote:
Friend claims 18 mpg while towing 35' toy hauler with 2003 Dodge Cummins Diesel with manual transmission. He says he never goes over 55 mph. Is he for real?

I assume he isn't an imaginary friend. Unlikely but possible if he doesn't always refill the tank to the top.

Old-Biscuit wrote:
Nope........

Best bet 13 mpg towing

IS his claim 'hand calculated' OR via the 'Lie-O-Meter'?

Exactly the same here and my TT is probably a lot smaller and lighter than your friends.

He probably has a programmer on it and they often cause the overhead to be way off.
Either way, there's no way he gets 18 towing.

Have a 2014 Dodge 2500 Cummins 6.7L, 32' 5th Wheel, towed several times this summer. It's a huge improvement over my 01 Chev 2500 6.0L but still only averaging about 12.5 MPG

Tvov wrote:
Especially if the dashboard mpg is "instant" mpg instead of averaged. Go downhill, mpg could jump to 50mpg. Also he may have "hand calculated" mpg once under ideal conditions, instead of calculating on a regular basis to once again get an average mpg.

Man that is really bad, only 50 mpg instant going down hill! :B

I can get a reading of 99 mpg coasting downhill with the engine running.

My Lie-o-meter is only off by 1 mpg when hand calculated. :)

PS: I never look at the instant when towing up hill! :S