MPG for SRW vs DRW

[Dave e Victoria]

As to the topic, Our present truck is a 2006 DRW 4x4 GMC D/A. It gets 15 mpg running empty mostly around town - about half freeway. Our previous truck was a 2003 SRW 4x2 GMC D/A. It got 17 mpg on the same mission. Towing, the 2003 got about 1. mpg better.
Dave

[nailbender]

Dave, Were both trucks 3500's and have the same gears. One mpg more would certainly help if driving many miles a year.

[Dave e Victoria]

The 03 was a 2500. Bubba is a 3500

[Capt Kidd]

Nailbender, I have the Dodge 3500 Mega Cab 4x4 with 4.10s and one size up in tires. I have the 6.7 liter motor. Single real wheels.

I absolutely love the truck and the way it tows. If you look up the specs a SRW is rated to carry more and tow more. I guess that is because of the extra weigh of the DRW setup.

We have not quite 20K on the truck and average between 9.5 and 10.5 mpg that is with the cuise set at 1700 rpm which is about 62 mph. Did a trip two weeks ago down to Plymouth and keep it at a steady 55 mph and did not get an better mpg. Depends on headwinds and such. I opted for the 4.10s because I will eventually trade the Monty for a bigger Monty and I wanted the pulling power.

With the six speed auto your overdrive in 6th is .6 and .8 in fifth with 4th being 1 to 1.

If you would check the Dodge truck forums I'm sure someone can tell you what the difference in mpg would be between the 3.73s and the 4.10s. Remeber Dodge is giving you fuel for 2.99 per gal for three years.

[TLightning]

quote:Originally posted by Capt Kidd


If you look up the specs a SRW is rated to carry more and tow more. I guess that is because of the extra weigh of the DRW setup.

I'm not up to speed on the new Dodges, but I cannot believe a srw can carry more than a drw...doesn't compute...that's the reason for the dually, to haul the heavy load. As for towing, with the GMs, the dually tows more, not less than the srw...and the dually's GCWR is 1500# higher.

[Delaine and Lindy]

Over the years I have given my recommendation on the DRW vs SRW Trucks. I base my opinions on over 50 years experience and having driven and owned many Trucks. Its got to the point that there are some who believe that the DRW and SRW are the same. And that the SRW can carry and tow more than the DRW's.

I now have come the conclusion some will never believe or think there is a difference in 3/4 ton vs 1 ton Trucks DRWs vs SRWs. I drive a 1 Ton Truck and I know its needed for what I tow. If you tow a 15,000 to 16,000 lb 5th wheel which has been on a Cat scale you need at a minimum of a 1 ton DRW Truck, and thats just a fact. Good Luck on your choice. GBY...

[blarkman]

Trailer life mag put out each year a list of tow vehicles and capicitys. There is a section on single vs dual wheel trucks. As I read it you do not save by going to drws unless you have a heavy load and the srw gets better milage due to weight. I know that I get better milage then my friend, same trucks same rv only he has a 4x4, both srw.

[richfaa]

The OP asked what the mpg difference was between SWD and DWD. many of us, including myself, gave answers that are not related to his question. There of course has to be a difference..less weight.. better MPG. I personally have no idea how much.My guess would be that the exact same truck..One single wheel and the other dually..The SWD would get a bit better MPG.. There are of course many other considerations..but the OP was only asking about the MPG difference.

[cmp-shooter]

I HAVE A 2006 3500srw D/A GMC and now have 21,000 on it, and when NOT towing and on highway my mileage is 20 to 22 mpg according to the steer column readout... when towing the montana and the truck was new I got 10 mpg.. now with 21000 on it I took the tana to the dealer to get the frig recall done yesterday and checked it and was getting 11.5 mpg now.

[indy roadrunner]

I work for a trucking company with over 6,000 units in the fleet. You can imagine how important fuel efficiency is for us. In a study we are doing using information from Cummins here is some things to consider. Exact same truck configuration, exact same weight, exact same route you can vary MPG 20 - 30% as result driver behaviors.
But in the study and back to the OP tires can account for 4 - 6% of MPG. According to Bridgestone, the tire tread accounts for 60-70% of the tires' rolling risistance. Not only do the tires differ in rolling resistance when new, but as the tread wears, the rolling resistance of the tire changes. A 7/32 tread wear represents a reduction of 10% in rolling resistance equating to 5% increase in MPG compared to a new tire.
As tires wear down the rolling resistance decreases and the fuel economy will go up. The max fuel economy of a tire will occur at around the 50% mark on the tread life.
Tread patterns are important because lugs patterns have deeper tread (More rolling resistance) than ribs. A new lugged tire is less fuel efficient by about 6%. With dual tires you are adding more resistance or road friction and with all things equal have less MPG than single wheel. Question is - much rubber is touching the road. Now with all that said you still have the weight factor of what a single wheel vs a dual wheel can carry.

[TLightning]

quote:Originally posted by blarkman

Trailer life mag put out each year a list of tow vehicles and capicitys. There is a section on single vs dual wheel trucks. As I read it you do not save by going to drws unless you have a heavy load and the srw gets better milage due to weight. I know that I get better milage then my friend, same trucks same rv only he has a 4x4, both srw.

The TL Towing Guide has lots of information and lots of it is confusing. They do not mention cargo capacity anywhere...which is the key difference between a srw and drw truck. The only thing they mention is "tow limit." The towing guide is very similar to the opinions of their so called 'experts' that are in each issue of the magazine...they put out totally incorrect information, and I don't have much faith in them.

[bigmurf]

quote:Originally posted by indy roadrunner

I work for a trucking company with over 6,000 units in the fleet. You can imagine how important fuel efficiency is for us. In a study we are doing using information from Cummins here is some things to consider. Exact same truck configuration, exact same weight, exact same route you can vary MPG 20 - 30% as result driver behaviors.
But in the study and back to the OP tires can account for 4 - 6% of MPG. According to Bridgestone, the tire tread accounts for 60-70% of the tires' rolling risistance. Not only do the tires differ in rolling resistance when new, but as the tread wears, the rolling resistance of the tire changes. A 7/32 tread wear represents a reduction of 10% in rolling resistance equating to 5% increase in MPG compared to a new tire.
As tires wear down the rolling resistance decreases and the fuel economy will go up. The max fuel economy of a tire will occur at around the 50% mark on the tread life.
Tread patterns are important because lugs patterns have deeper tread (More rolling resistance) than ribs. A new lugged tire is less fuel efficient by about 6%. With dual tires you are adding more resistance or road friction and with all things equal have less MPG than single wheel. Question is - much rubber is touching the road. Now with all that said you still have the weight factor of what a single wheel vs a dual wheel can carry.

How about when the tires wear out,do they become smaller? Therefore changing the gear ratio?