2500hd 6.6l gas enough

[James Beyer]

Hey all, have a 2024 gmc 2500hd doublecab with 6.6l Gas 4x4 and currently towing a 9000 pound, 35' Rockwood TT with No Problems. 

We are looking at a 37' Grand Design fifthwheel with 11,000 pounds dry weight, and 14,000 pounds gvwr.

Mainly Camping in Northern Michigan, but wondering if the 2500hd 6.6l gas is enough if I take trips to Alabama?

Thank You,

Later

 

Edited March 20 by James Beyer
up

[Jettech1]

I have a 22 gasser with the 5th wheel package and would not hesitate for a second to hook up a 16k lb camper to it, and that's with the 6 speed.  I believe yours is the 10 speed which makes it even more doable.  Just my opinion and COME on down to BAMA!!!  Look up lake Martin campground.  It's like 15 minutes from where we live.  Biloxi has a lot of great places to stay as well right on the ocean.  Only a short drive from Mobile.  Enjoy sir and hit me up if you all stay at Lake Martin.  Beautiful place to camp, heck we put our camper there for a couple weeks at a time while I still work in Dadeville, AL.  Let me know, it would be great to see another forum member and trade notes on our campers and trucks!

 

Dale

Edited March 19 by Jettech1

[James Beyer]

14 minutes ago, Jettech1 said:

I have a 22 gasser with the 5th wheel package and would not hesitate for a second to hook up a 16k lb camper to it, and that's with the 6 speed.  I believe your's is the 10 speed which makes it even more doable.  Just my opinion and COME on down to BAMA!!!  Look up lake Martin campground.  It's like 15 minutes from where we live.  Biloxi has a lot of great places to stay as well right on the ocean.  Only a short drive from Mobile.  Enjoy sir and hit me up if you all stay at Lake Martin.  Beautiful place to camp, heck we put our camper there for a couple weeks at a time while I still work in Dadeville, AL.  Let me know, it would be great to see another forum member and trade notes on our campers and trucks!

 

Dale

Thank You Dale, very good news that this 6.6l gas will be enough.  Yes, you are correct, I have the 10 speed.  Will look up Martin Campground, like new places and new friends.  Looking forward for the future, Later-

[Byrds8]

I thought the tow ratings were in the door jam? I think mine even says for fifth wheel/gooose neck it will do around 18K.

[BuckWallace]

The only concern might be the pin weight on that 5th wheel. Some 2500s don't have a very high max pin weight, so that could be the limiting factor. Also, your L8T can handle the overall GVWR, but if you're towing that much very frequently your quality of life (towing) would be much more pleasant with a diesel. Good luck with whatever you choose!

[James Beyer]

Hey Byrds8, yes my payload is there but not fifthwheel, just didn't want to push it to the max of what it really can do, not GM numbers.

Hey Buck, my payload is 3534, so I should be fine there, we'll at least until my wife starts packing.  No doubt a Diesel would be much better, but 90%+ of my driving is Grandchildren to school and 10 mile trips to town.

Thank You both for your suggestions,

Later-

Edited March 20 by James Beyer
add

[UWSkier]

Michigan to Alabama is pretty low and flat.  You'll be fine.  If you lived in the west, I'd encourage a trade.  I tow a smaller TT than you do and wish I had the diesel above 6000' elevation or in strong winds.

[No F-bdy Bs]

Depending on how often you make the trip I'd say you're right on the edge, and that's me with the mindset that a person should do everything they can to avoid a diesel. 

 

Flipside is if you've got a pile of $, then buy whatever you like. Hell, if I had the cash, I'd have a red badge 6.7 HO powerstroke tomorrow even though I don't tow much over 10k.

[James Beyer]

Thank You UWSkier, I was towing this TT with a 1500, max tow, until afm started, and went up 2500hd.  Big difference in towing especially with wind, but not sure on mountains yet.

 

Thank You No F-bdy Bs, lol no money pile here, just planning the future.  Never had a diesel, but lots of friends that do, they love them for towing their fifthwheels.  But, our current routine of small daily miles with Grandchildren is probably not ideal for the diesel engine.

 

[rjgvt]

If you have the 5th wheel option on your truck, the gooseneck tow rating and pin weight should be on the sticker.

[Jettech1]

Let me try to clear some things up here because I can see some confusion.  I'm not the God of anything, but I do know my stuff when it comes to towing.  

 

First let's start with payload and tongue weight.  As we know payload is amazingly high on our 2500's especially the gassers that are lighter than the diesels.  So let's say the 2500 gassers have an average payload of 3500lbs, of which most do.  Now that includes everything added to the truck, people, cargo, you name it, everything is added into that payload number.  Tongue weight is also included if you have a hitch pulled Travel trailer. 

 

For example, we have a Grand Design Imagine 2800BH.  We filled it with all of our stuff, including the fridge, I filled the fresh water tank too (55Gallons) because it is forward of the axles then took it to the CAT scales and weighed that beast.  The results were I had 7k on the axles and 1k on the tongue.  Believe it or not my rear helper springs were not even contacting the base pack of springs.  Not bad at all when you have 3500lbs to play with.  

 

Now, let's talk about 5th wheel and pin weight.  10% of the overall weight of what you are towing is the golden rule.  So if your giant ass camper weighs 16k, you are looking at 1600lbs of pin weight that is over the rear axles.  Totally different weight placement when compared to a hitch travel trailer.  Now that 1600lbs reduces your payload by.....1600lbs.  But you still have basically 1900lbs of payload left to play with.  

 

So let's talk about the other basic rule of towing.  Stay within 75% of max capabilities for safety reasons.  So your 1900lbs, for safety reasons becomes 1425.  Not bad at all, actually quite impressive.

 

You can add air bags, timberens, whatever, just remember those items do not increase your overall payload number.  Payload is payload, it's a hard number.  Those items might level out your truck and make it ride better, but they never increase your payload.

 

I really hope this helps others and makes a lot of sense.  Safety is #1.  The rest is enjoy the ride because these HD trucks are friggen amazing!!!

 

One other thing I forgot to add is that I no longer use sway bars for our travel trailer.  To me they are useless and serve little purpose.  Pump your E rated tires up to 75psi, and hopefully your campers have e-rated tires as well.  Pump them up to 75psi too.  Not a problem at all towing.  Sway is minimum and I love not using them.  They really are a pain in the ass.  The 1500 guys have to use them, us HD guys.....throw them away....they are useless.  Just my personal opinion all after towing our camper thousands of miles.

 

Be well and if you have any questions, I might be able to help.

[James Beyer]

Thank You rjgvt, I don't have the 5th wheel option on my truck, unfortunately.

 

Jettech1, wow, Thank You for the great explanation of towing TT and 5th wheels payload, much appreciated.

 

 

Edited March 23 by James Beyer
dang spell check

[Jettech1]

10 hours ago, James Beyer said:

Thank You rjgvt, I don't have the 5th wheel option on my truck, unfortunately.

 

Jettech1, wow, Thank You for the great explanation of towing TT and 5th wheels payload, much appreciated.

 

 

I'm here to help sir.  Do I know it all....NO....but have I done a lot of reading and real world use...YES!!

[newdude]

On 3/20/2026 at 3:21 PM, James Beyer said:

yes my payload is there but not fifthwheel, just didn't want to push it to the max of what it really can do,

 

 

Look again.  Its there.  

 

Gray sticker on the face of the door jamb between the two doors.  Has the VIN, curb weight, payload, conventional tow rating, 5th wheel tow rating, GVWR and GCWR.

 

Here is an example from a different truck of that label:

 

Edited March 27 by newdude

[James Beyer]

4 hours ago, newdude said:

 

 

Look again.  Its there.  

 

Gray sticker on the face of the door jamb between the two doors.  Has the VIN, curb weight, payload, conventional tow rating, 5th wheel tow rating, GVWR and GCWR.

 

Here is an example from a different truck of that label:

 

Hey new dude, mine is different than yours, not sure why