What should I expect in MPG while towing my RV

[acoffeefiend]

I have a 2016 1500 5.7 hemi crew cab 8 spd. 275/60r20 KO2'sI pulled a 28ft keystone cougar. Dry weight was about 5800lbs, but with water, propane, camping gear, etc, it came closer to 7000lbs. I got avg 8mpg. It sucked going up any type of hill. Going up a 7% grade I was stuck at 30mph. I never drove it over 60mph when towing.

I'm now at 100K miles and am upgrading to 4.56 gears and 35" tires and a 3.5" lift. The towing capacity should go up significantly.

 

[2003F350]

I have a 2016 1500 5.7 hemi crew cab 8 spd. 275/60r20 KO2'sI pulled a 28ft keystone cougar. Dry weight was about 5800lbs, but with water, propane, camping gear, etc, it came closer to 7000lbs. I got avg 8mpg. It sucked going up any type of hill. Going up a 7% grade I was stuck at 30mph. I never drove it over 60mph when towing.

I'm now at 100K miles and am upgrading to 4.56 gears and 35" tires and a 3.5" lift. The towing capacity should go up significantly.

It...really won't. The only thing you're helping yourself with is the 4.56 gears. Lift and tires do nothing to help your towing capacity. Gears don't change your rated towing capacity.

The only thing that can change your rated towing capacity is getting it certified by DOT.

Now, will it handle the load better with 4.56 gears? Yes. It will get up to speed quicker. But it won't stop or corner any better. Adding a lift and tires will make it handle worse when towing.

 

[Riccochet]

Lift and tires does not change the axes rated capacity.

If anything you're just going to make it tow worse.

 

[heefageLA]

Put this in another thread also, but the DropBox link below has a Fuel Consumption Calculator that I made. It has formulas built into it that calculate your Average MPG and Cost Per Gal. of fuel. All you need to write down when you fill up is your Total Gal., Total Cost, and Odometer then plug that into the spreadsheet. Its a nifty way to track your MPG without having to keep a written record and saves a ton of time.

Dropbox

www.dropbox.com

 

[Tulecreeper]

It...really won't. The only thing you're helping yourself with is the 4.56 gears. Lift and tires do nothing to help your towing capacity. Gears don't change your rated towing capacity.

The only thing that can change your rated towing capacity is getting it certified by DOT.

Now, will it handle the load better with 4.56 gears? Yes. It will get up to speed quicker. But it won't stop or corner any better. Adding a lift and tires will make it handle worse when towing.

Lift and tires does not change the axes rated capacity.

If anything you're just going to make it tow worse.

Yes, changing the gear ratio will only get you moving off the line smoother. At highway speeds there will be no difference.

 

[Randy Grant]

It...really won't. The only thing you're helping yourself with is the 4.56 gears. Lift and tires do nothing to help your towing capacity. Gears don't change your rated towing capacity.

The only thing that can change your rated towing capacity is getting it certified by DOT.

Now, will it handle the load better with 4.56 gears? Yes. It will get up to speed quicker. But it won't stop or corner any better. Adding a lift and tires will make it handle worse when towing.

True, and larger tires will negate the gear change, so no gain.

 

[tron67j]

I have a 2016 1500 5.7 hemi crew cab 8 spd. 275/60r20 KO2'sI pulled a 28ft keystone cougar. Dry weight was about 5800lbs, but with water, propane, camping gear, etc, it came closer to 7000lbs. I got avg 8mpg. It sucked going up any type of hill. Going up a 7% grade I was stuck at 30mph. I never drove it over 60mph when towing.

I'm now at 100K miles and am upgrading to 4.56 gears and 35" tires and a 3.5" lift. The towing capacity should go up significantly.

You should go get an actual scale reading of your fully loaded rig with everything and everyone in it. With limited information to go on, best guess is you are pushing above your max GCWR. That is ALWAYS first step when towing isn't a decent experience. Throwing money at a perceived issue could totally miss the target. Higher gears are going to work your engine harder in normal use, so you may be trading up to a bigger problem long term.

 

[acoffeefiend]

You should go get an actual scale reading of your fully loaded rig with everything and everyone in it. With limited information to go on, best guess is you are pushing above your max GCWR. That is ALWAYS first step when towing isn't a decent experience. Throwing money at a perceived issue could totally miss the target. Higher gears are going to work your engine harder in normal use, so you may be trading up to a bigger problem long term.

It's a good point, but I've done the math. 4.11 gears and 35" tires gives you the equivalent of 3.91 gears and 33" tires which was an option on my truck. Doing 75mph in 8th gear my RPMs should only go up about 300rpm with the 35"s and 4.56 gears and I'll definitely stay under the 12K that the truck is rated for with the 3.91 gears.

 

[acoffeefiend]

It...really won't. The only thing you're helping yourself with is the 4.56 gears. Lift and tires do nothing to help your towing capacity. Gears don't change your rated towing capacity.

The only thing that can change your rated towing capacity is getting it certified by DOT.

Now, will it handle the load better with 4.56 gears? Yes. It will get up to speed quicker. But it won't stop or corner any better. Adding a lift and tires will make it handle worse when towing.

Yup. Just want to get up to speed faster and climb hills more easily. Not going crazy on the lift. 3.5" and 35"s. Not towing any crazy weight.

Lift and tires does not change the axes rated capacity.

If anything you're just going to make it tow worse.

The truck with 3.21 gears is rated for about 8K towing. Same truck with 3.91 gears is rated for about 12K towing.... pretty sure the only real difference in the trucks is the gearing.

 

[Riccochet]

Yup. Just want to get up to speed faster and climb hills more easily. Not going crazy on the lift. 3.5" and 35"s. Not towing any crazy weight.

The truck with 3.21 gears is rated for about 8K towing. Same truck with 3.91 gears is rated for about 12K towing.... pretty sure the only real difference in the trucks is the gearing.

That is the only difference. That being said, going to 4.56 gearing won't increase your towing capacity. I wouldn't even tow 10k with a half ton. About 8k is the max I'd want behind a truck like that. You'll be running out of payload long before you ever get close to max towing capacity.

 

[WY-Dave]