Gas vs Diesel for towing vehicle

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

gartash

New member
Joined
Jan 2, 2012
Posts
1
Hi. I am new to this forum and looking for some advice. We currently own a 18 foot bumper pull, but looking to go with a larger 5th wheel hopefully this year some time. We will also be purchasing a new tow vehicle. I am debating whether the extra money for a diesel engine is worth the extra cost on the price tag. We will be doing some mountain traveling where the power will be helpful, but not all of our trips will be this straining. We are considering at this time the Chevy 2500hd whether it be gas or diesel. Any suggestions, opinions, or thoughts would be appreciated. Thank you.
 
I have a 2008 Chevy 2500HD with the 6.0 Gas engine and it does ok, but not great. I live in SW Missouri and we have some pretty decent hills around here and I struggle a little  with our 8000 pound 5th wheel. I'm ok if I can get a good run at them but if it's one long continuous hill I start really slowing down about half way up. I wish I would have waited and gotten a diesel. From everyone I talked to there is no comparison. One instance I remember I was pulling up a steep hill and only going about 40 when a 2500HD diesel pulling a 5th wheel about the same size as mine passed me like I was sitting still - - the speed limit was 70mph. The gas trucks are definitely cheaper but I think in the long run you'd be happier with a diesel especially if you are going to be traveling in the mountains.

Also - I get about 10mpg with my trailer....a lot of the Chevy 2500's only have a 26 gallon tank. I didn't realize that when I bought mine and it drives me crazy to only be able to go 260 miles on a tank. 200 safely. I know the diesels have a 34 gallon tank and I've heard they get better mileage.

Hope all that helps.
 
Before buying ANY trucks, first you must decide how much trailer you are going for.  Gas motors are fine for towing up to about 10,000 pounds.  Anything over that get a diesel.  Also please forget a 2500 (3/4 ton) trucks.  You will run out of load capacity long before you get much trailer.  A fifth wheel will place approx 20% of it's loaded weight directly over the rear axle.  So even a 10K fifth wheel will put 2000 pounds on the truck.
 
If you do any mountain/hill towing at all, you will be glad you got a diesel.  You're going to see some opinions where a gasser will be fine, but believe me, you will be much happier with the diesel, even without the mountain/hilly towing. 

I don't believe you need to "forget a a 2500".  Unless you get into the 5th wheels that are pushing beyond 12,000 GVWR, a 2500/250 should be just fine.  But you do have to be aware of the weights and buy a truck that will be capable of handling it.  In other words, look at and buy your trailer first.  Then you can be sure and get enough truck to match it.

One more thing...always use GROSS vehicle weight rating (GVWR) when figuring your weights, not the dry weight.
 
Each response above brings up a valid point but the over-all consensus you're going to get from those of us who drag these things around is that diesel is the way to go. On the other hand you have to gauge your decision based also on how much traveling with this rig that you are going to do. If your simply heading out for a weekend once every month or so you might not need the added expense of a diesel truck. Conversely, if you plan on part-timing or snow-birding you'll definitely want a truck without spark plugs.
 
donn said:
Before buying ANY trucks, first you must decide how much trailer you are going for.  Gas motors are fine for towing up to about 10,000 pounds.  Anything over that get a diesel.  Also please forget a 2500 (3/4 ton) trucks.  You will run out of load capacity long before you get much trailer.  A fifth wheel will place approx 20% of it's loaded weight directly over the rear axle.  So even a 10K fifth wheel will put 2000 pounds on the truck.


Don't believe this about a properly set up gas truck, we started pulling a 16K 5ver in 01 when our Ford V10 gas truck after we traded in our 12K 5ver. Our present trailer and truck grossing at 24K has been in 49 states and 6 provinces over Berthoud Pass (11307 ft) in CO pulling out 14.5 ft boat behind the trailer every year. Just look at all the class A motor homes that are gas they are all over 10K and pulling cars behind them without any problems. Unless it's a light trailer I would go with a one ton but the ratings on most of the trucks have really changed in the last few years so I would do my own homework to make a decision on what TV in best for your situation.

Denny     
 
If you can (or if you "want to") afford the diesel, go for it - yes, they make towing easier. However, I stuck with gas when I purchased my 2010 Sierra. Here are my thoughts:

aterry said:
I have a 2008 Chevy 2500HD with the 6.0 Gas engine and it does ok, but not great. I live in SW Missouri and we have some pretty decent hills around here and I struggle a little  with our 8000 pound 5th wheel. I'm ok if I can get a good run at them but if it's one long continuous hill I start really slowing down about half way up.
Our TT weighs in at about 8,500 lbs. I am actually quite happy with my gasser's performance. I still slow down on the hills and get passed by the diesels but overall,  this motor is much stronger than the 2002 6.0L I replaced.

aterry said:
Also - I get about 10mpg with my trailer....a lot of the Chevy 2500's only have a 26 gallon tank. I didn't realize that when I bought mine and it drives me crazy to only be able to go 260 miles on a tank. 200 safely. I know the diesels have a 34 gallon tank and I've heard they get better mileage.
I also get about 10 MPG overall towing. Diesel milage will be better. I know with the gas motor, gas tank size depends on box length: 6.5' = 26 gals and 8' = 34 gals. Not sure if that holds true for the diesels or not.

donn said:
Also please forget a 2500 (3/4 ton) trucks.  You will run out of load capacity long before you get much trailer.  A fifth wheel will place approx 20% of it's loaded weight directly over the rear axle.  So even a 10K fifth wheel will put 2000 pounds on the truck.

I disagree (with "forget the 2500" comment) - based on my owner's manual, the 3500 identical to my 2500 actually has slightly LESS load capacity since the truck is heavier and they have the same 18,500 GCWR. Also, if you move up to a diesel engine, the diesel engine is heavier so it will lead to lower load capacity (which translates to pin weight). You have to look at ALL the numbers, not just max tow rating.
 
I had 1997 Dodge dually work truck with a gas v-10 pulling a 24 ft. cargo trailer around 10,000lbs.  Didn't hold up. Traded for a 2004 Dodge Ram dually with a 5.9-liter Cummins turbo diesel.  It was a difference of daylight and dark!  The diesel ran like a sewing machine, never broke down.  Personally I prefer the ton over the 3/4 ton.
 
I'm also a DodgeRam 2500 Cummins Diesel powered... Much more torque for pulling heavy trailers and cost of operation is much less than any gasoline power tow vehicle. I'm pulling a 31' Jayco Eagle Travel Trailer (8,500# GVWR) and my gross combine weight is roughly 16,080# the last time I checked. I've zero problem pulling over a 6-7% grade and last trip I was getting 14.1 MPG...Hard to touch with gasoline powered vehicles.
 
Foto-n-T said:
the over-all consensus you're going to get from those of us who drag these things around is that diesel is the way to go.

What he said.
If you can afford it, get the Diesel--you won't regret it.
I'd say go with the 1 ton vs 3/4 ton as well.  I don't think the price diffrence is that great between them and this way as you upgrade trailers, you know your good to go with a 1 Ton Diesel...
 
What about the price difference in gas vs diesel FUEL right now?  It's about .60 per gallon MORE for diesel fuel where I live.  Will the better fuel efficency with a diesel even this out?  Do you really get better with diesel?
 
Yes diesel costs more today than it did prior to 2007 when the government forced us into using ULSD (Ultra-Low Sulphur Diesel) versus the easier to produce LSD (Low Sulphur Diesel). The fuel mileage difference probably won't make it cheaper on fuel to operate but the cost of the fuel is only a part of the equation.

Gasoline engines DO NOT have the life-span of a diesel engine. My truck currently has 340k on the original engine (Cat) and I would expect to see at least 500k on this particular small diesel motor. I personally have seen Ford Power Stroke (International) 7.3 liter V8's go in excess of 750k. If properly cared for a light truck or medium duty truck diesel engine will outlast any light truck gasoline engine by 400% (my opinion).

You also need to factor in the transmission attached to either engine. Automatic transmissions behind diesel engines are engineered for a much higher torque rating and in general should prove to be more durable. Having said this, as a professional driver I loathe towing a heavy load with an automatic transmission. There's a reason you don't see too many of them on Class 8 trucks. It doesn't mean they won't work, it just means that when you break an auto you'd better have DEEP pockets.

It's all a matter of what best suits "Your" needs. Having a Medium Duty Truck can be a major pain when it comes to using it to run small errands. Having a Light Duty pick-up with a diesel engine can be a financial disaster if you mainly use it for short trips and a lot of starting and stopping. In these cases a gas engine would probably be better. But if you're going to use the truck for long trips where the engine gets started and not shut off for 12-14 hours at a stretch this is where the diesel engine shines. Diesel engines DO NOT like to be treated like gas engines when it comes to short trips and and run times.
 
My wife and I pulled our fifth wheel from pa to nc and back. My Dodge diesel  made the trip easy. Hills are easy now. Exaust brake a must. Truck stops for fuel is very nice to get in and out. Mileage much better than gas. Torque with a diesel is better than a gasser.
 
Either gas or diesel will work when the combined truck/trailer match is correct. Just as you are upgrading now most of us have upgraded several times(unfortunately) as our requirements have changed. Only you can evaluate which is the best truck for your needs. As most have suggested choose the trailer you want first. If you can get a accurate loaded weight that will drive the truck decision. As a general rule most use 20% of the trailers GVWR for payload info. This is for a 5th wheel only. Either way you go, highly recommend you look at a 3500 HD (1 ton).

FYI, I pull a 12K 5th wheel with my 2011 SRW 4X4 DMAX and with only 5800 miles on her, hand calculated I "average" 12.51MPG towing, in town empty 14.4MPG and hwy empty 18.6MPG. All in all I'm very happy with these numbers. While gassers may get better MPG in town and hwy, a diesel will generally out perform towing.
One other item I will mention is on new diesel trucks the "Exhaust Brakes" are outstanding. Especially the GM's.

Good luck on whatever you decide.
 
Diesel fuel has about 15% more energy than gasoline, so any price difference that exceeds 15% means you are paying more per mile. Gas is running about $3.26 a gallon where I am today, so diesel could cost up to $3.75 and be cost effective.  Diesel prices are running from $3.60-$3.85 in the same area.

Efficiency - how much fuel is needed to move a given weight, is a different question. I'm not sure any fuel is inherently more efficient than another, but a diesel engine runs at much lower RPMS than gas for equivalent horsepower and torque and I think that would reduce power loss due to mechanical "slop" as well as reducing long term wear. The less things move, the less is lost to friction.
 
The biggest problem with the average gas truck on the lot is it's set up with gears that belong in a low rpm diesel truck, gas and diesel motor are two different animals and they need to be geared differently to be a good pulling motor. Gas motors are higher rpm motors and need lower gears (higher numerical numbers) to keep the motor in its power range just like a diesel needs higher gears to keep it in its power range. You will also find that a gas motor with lower gears will get better millage pulling and empty (if you keep our speed down empty) than one with higher gears because the motor doesn't have to work as hard also the running gear like the transmission will last longer because of less stress. Class A motor homes don't have this problem because they come with the right gears from the factory unlike trucks that you have beg a dealer to order one geared the right way because they all believe that higher gears mean better mileage. You have to remember that the newer generation gas motor are made to run at higher rpms compared to older ones. I have to LOL when I here someone say they would never pull with a gas motor again but when you question them they had a gas motor with high gears so it had to work its butt off to pull their trailer but the diesel just cruises along with the same gears and rpm but the gas motor was not in its power band like the diesel. We started RVing in 1978 and every used truck we bought before we started buying new I had to change the rear end gears to make them pull the intended load also keep a eye on the tire size because bigger tires raise the final gearing where the rubber meets the road.

Denny

Denny 
 
You can't buy a V10 anymore so if you go with a gas engine it will be the small V8.

I bought the V10 because it was the 6.8L and gas was cheaper than diesel. Plus service was cheaper. My next vehicle is going to be a diesel because the little V8s don't pull mountain grades very well.
 
No regrets here, love the diesel going up the grades with our unit.
 
I have driven many different vehicles with both gas and diesel engines and came to the conclusion over 20 years ago that diesels are meant for towing. Does this mean that their overall operation will be cheaper? No, but the towing experience will be more enjoyable. With the new high power diesels, there is no comparision with the exception of tires. A gas engine vehicle will get more life out of it's tires because it doesn't have the torque to peel the rubber off like a diesel. As far as mileage goes, if you drive the same trailer at the same speed, the diesel will get a little better fuel ecomomy than the similar gasser, but add a head wind, or lots of hills and the diesel will greatly out pace the gasser. The other thing about the diesel is you will have the ability to easily maintain the posted speed limit which might not be so easy with the gasser. When the guys with the gassers say they get 10 mpg towing their big fiver, let's have them run it next to me towing my 5er. I will get an honest 10-11 mpg with a gvw from 20 to 26k I have yet to see a gasser that can match  this mileage with the same type load. I used to have a new Dodge 3500 with a V-10 and 5 speed. I towed a fairly heavily loaded  20ft enclosed trailer from Worland, Wy to Cheyenne, Wy about 400 miles. Between Casper and Cheyenne running down I 25, I got 3.8 miles per gallon. Nuff Said!
 
No question about it, my 6.8L V10 won't do the job that my 7.2L diesel did, especially over the passes. I would have kept that diesel except it was 2WD. Didn't like walking a couple of miles up hill to our ranch in the winter time. LOL. 
 

Forum statistics

Threads
131,749
Posts
1,384,212
Members
137,520
Latest member
jeep3501
Back
Top Bottom