Safe towing weight limit

[gary_lucas]

We're about to buy a 5th wheel.

I'm adding up the numbers and it's looking right on the edge of what is doable with my 2500hd.

Payload on the door sticker is 2500lbs (2495 or something but close enough).

The dry hitch weight of the 5th wheel were looking at is 1505.

That leaves about 1000lbs leftover, with me, my wife and fuel and assorted gak we're probably right on the number.

Once we get setup I'll have to weigh it.

What's the general feeling amongst the group, would I be pushing my luck? Should I get an extra leaf spring / super spring?

I know we'll be nowhere near the axle / tire limits.

My gut feeling is it's probably fine and if I notice any sag I'll get a spring installed... I'm not expecting any problems as if we're over it'll be by about 50lbs... And probably not even that.

[a5150nut]

Air bags for the back axel. If you can the on board compressor and controls are nice. Whats the length of you 5er?

[gary_lucas]

Probably going to be just a touch over 31 feet.

We're looking at two, the other one is a little shorter, 27 1/2 feet. A little lighter too.




Air bags for the back axel. If you can the on board compressor and controls are nice. Whats the length of you 5er?

[DmaxMaverick]

Probably not much to worry about. Airbags help a lot with stability, but won't increase the load capacity. Unless those RV's are VERY heavy (3 axle toy hauler, loaded to the gills), don't sweat it. The large one you're looking at is smaller than the smallest I've had. Legal weight, or close enough to it.

[gary_lucas]

That's kind of what I figured.

GCWR will be nowhere near max (75% of the rating) and if we're over payload it'll be by a hundred lb's at the most.

I wasn't so much concerned as curious.

If it does sag you suggest airbags over super springs or an extra leaf in the suspension?

Thanks much :)

G


Probably not much to worry about. Airbags help a lot with stability, but won't increase the load capacity. Unless those RV's are VERY heavy (3 axle toy hauler, loaded to the gills), don't sweat it. The large one you're looking at is smaller than the smallest I've had. Legal weight, or close enough to it.

[DmaxMaverick]

I recommend airbags. There are other less expensive options, but they aren't adjustable (as easily), and certainly not adjustable on-the-fly. I've used several solutions over the years, and the airbags are head and shoulders above the rest. There are also other options with them, such as remote pressure control (wired or wireless). As with anything, more money gets you more features, most of them are worth it. I have the Airlift bags and wired electronic controller. There wasn't a wireless system available when I did mine, or I would have paid more to get it. Installation wasn't difficult, but it would have been about 1/2 the time/effort. I've also installed this system into several friends' rigs. No complaints. I'm not a salesman, nor am I related in any way with those who sell or make them. Just a satisfied customer.

[a5150nut]

IIRC, several years ago there were a couple members here that went with the air bags and removed the heavy leaf spring to get a better ride empty.

[DmaxMaverick]

IIRC, several years ago there were a couple members here that went with the air bags and removed the heavy leaf spring to get a better ride empty.

You could do this, but under normal conditions, it does nothing (other than lower the height by the thickness of the spring). The default "low" pressure is 5 PSI, which keeps it off the overloads, anyway. The default pressure is necessary for long-term airbag health (and Airlift extends the airbag warranty to lifetime with the electronic systems because of this, as the control will maintain a minimum of 5 PSI). At 5 PSI, the overloads are rarely ever in effect, and only contact on rough surfaces (like RR tracks, I can hear them, as my spring insulators are LONG gone). Good shocks (like Bilstein) help in this regard better than anything else. Airbags aren't perfect. They are only one effective answer to a pre-existing condition.

An added bonus of the onboard compressor and control, is a compressed air source for emergency situations. I've used it to air trailer tires (of course, the spare will be low or flat), motorcycle tires, and adjust the truck tire pressure after leaving the dunes. I install the system with manual air fittings at the rear (the license plate bolt holes work well for this), and have 50' of coiled 1/4" air hose with locking air chucks at both ends. Run the airbag pressure up to max, connect the hose and air away. It's slow, compared to a full size compressor, but it works. Of course, there are better solutions (such as a larger compressor and tank), but it just works.

[gary_lucas]

good to know, I'll see how the truck looks after we get the 5th wheel... If it's flaky I'll get airbags :)

G


I recommend airbags. There are other less expensive options, but they aren't adjustable (as easily), and certainly not adjustable on-the-fly. I've used several solutions over the years, and the airbags are head and shoulders above the rest. There are also other options with them, such as remote pressure control (wired or wireless). As with anything, more money gets you more features, most of them are worth it. I have the Airlift bags and wired electronic controller. There wasn't a wireless system available when I did mine, or I would have paid more to get it. Installation wasn't difficult, but it would have been about 1/2 the time/effort. I've also installed this system into several friends' rigs. No complaints. I'm not a salesman, nor am I related in any way with those who sell or make them. Just a satisfied customer.

[gimpyhauler]

Would a more distributed loading job help? Perhaps to much in front of the axles?

I'll admit I've never been near the limit but I have a 30/38' twin axle flatbed gooseneck trailer and when loaded the heaviest I've loaded (no idea of actual wt) with vehicles and construction tools & "stuff," my truck seemed to be fairly level.

[gary_lucas]

Ok, so bought the new 5th wheel today.

Haven't taken possession, that'll probably be in the next 2 weeks.

Couple of things. Hit the scale and I have hard numbers now.

Truck weights:
front axle 4598
rear axle 3674

GVWR 9200
Total Weight 8272

Pin weight 1500


Total with pin 9772

So I'm actually over by approximately 500lbs. That makes me nervous.

Now some of that weight will go into the trailer, probably about 150 lbs of it. I know to get airbags if I have level issues.

Based on the feedback so far I'm assuming I'm fine assuming good tires and safe driving.

This is all on the GMC 2500hd diesel 2004.5

G

[Mark Rinker]

Ok, so bought the new 5th wheel today.

Haven't taken possession, that'll probably be in the next 2 weeks.

Couple of things. Hit the scale and I have hard numbers now.

Truck weights:
front axle 4598
rear axle 3674

GVWR 9200
Total Weight 8272

Pin weight 1500


Total with pin 9772

So I'm actually over by approximately 500lbs. That makes me nervous.

Now some of that weight will go into the trailer, probably about 150 lbs of it. I know to get airbags if I have level issues.

Based on the feedback so far I'm assuming I'm fine assuming good tires and safe driving.

This is all on the GMC 2500hd diesel 2004.5

G

My advice? Trade up to a 2006 K3500 dually.

[gary_lucas]

Seriously? That sounds like serious overkill.

I'm nowhere near any of my other capacities.

GCVW is about 75%.
Axle weights are about 75%

Previous owner put 265's that are rated for 3400lbs (each) on it as well, so their probably more like 70% of their rating.

Kind of makes me laugh too, because the 5th wheel we picked up is '1/2 ton towable' I can't imagine how those numbers work out... I guess if there's no one and nothing in the truck it works...




My advice? Trade up to a 2006 K3500 dually.

[AKMark]

I've pulled 12K from the Class V bumper receiver and never thought the truck couldn't do it.

Wish I had a gooseneck, but maybe someday....

[Mark Rinker]

Ok, so bought the new 5th wheel today....>>>

So I'm actually over by approximately 500lbs. That makes me nervous.

<<<

G



The author of this thread said he was 'nervous'...so my response was "Get more truck." :) i.e. create more margin of safety.

Personally I wouldn't be nervous with 10-12K# on a gooseneck with a 2500 series in good mechanical shape.

[gary_lucas]

Thanks for all the input, you've got a point regarding "Get more truck".

I'm picking up the 5th in 2 weeks, first trip will be up to hope on the long weekend. Should be fun. If I'm not riding level I'll get airbags installed quickly. I may even get them done when getting the hitch installed.

The funny part is I just put a 50 gallon tank in the bed of the truck... Guess what that and fuel weighs about 500lbs... My own damn fault. On the upside I've now saved enough in fuel costs to pay for the mods... That only took 2 months so I'm thinking that's pretty awesome.

Once i get my campsite and have somewhere i can do some actual work I may try to install super springs.

Also, if I were to go from 16" tires to 17 or 18 would i be looking for problems?

Thanks again, I'll get pictures of the truck and 5th up when I get back.

G

PS: a 3500 dually was on the menu when I was seriously considering a bigger truck camper... Wife kinda killed that. I'm still amazed she let me trade in our current camper for the 5th.

[Yukon6.2]

Hi Gary
Up sizing your tires will just cost you more money.
Unless you install bigger brakes there is no real reason for 17's or 18's.
You can buy the best michelin or toyo's in 16's for less than crappy 17 or 18's.
What size are the tires on your new trailer? Can you get 16's on it?
Then you could use your truck tires on it,and buy some good new ones for the truck.Sell the chinese tires that will come on your trailer while they are new and you should be set with good rubber for a good price.
My .02,which in Canada is now .00
Thomas

[gary_lucas]

That's all sounds good, the tires on the trailer are 15's,

So, not sure if I can get the 16's on the trailer, the 16's I've got are 265's, I'm assuming they'll be too big. But I'll check it out :)

Is it even possible to get bigger brakes on bigger wheels?

Gary


Hi Gary
Up sizing your tires will just cost you more money.
Unless you install bigger brakes there is no real reason for 17's or 18's.
You can buy the best michelin or toyo's in 16's for less than crappy 17 or 18's.
What size are the tires on your new trailer? Can you get 16's on it?
Then you could use your truck tires on it,and buy some good new ones for the truck.Sell the chinese tires that will come on your trailer while they are new and you should be set with good rubber for a good price.
My .02,which in Canada is now .00
Thomas

[Mark Rinker]

There are many threads here on the page that support the sage advice to leave wheel/tire diameter of diesel tow vehicles alone - or increase by no more than 5% over stock.

The ECM, TCM, gear ratio, brake hardware, etc. all work together to create a fantastic towing machine under a variety of altitudes, temperatures, loads, etc. In short, the truck that rolls out of the factory is nearly IDEAL. Changing tire size drastically requires rethinking all of the above, which is unlikely or $$$ impractical to do.

...especially if you intend to tow heavy. ;)

[Inspector]

I'm pretty sure that the published hitch weight of the 5th wheel is with an empty trailer. So the only way to know how much weight is in the bed of the truck is to road load it and then hit the scales. Am I right? If your weight on the hitch increases then your payload decreases in the truck. Keep in mind the max weight that the rear axle is rated at, you may have to lighten up the pin weight and leave some pots and pans home.
Denny

[gary_lucas]

That makes sense, it was related to something else I had thought about.

Whether it was possible to put bigger brakes on my truck or not, after doing some research awhile back I came up with the same thing you said.

IE it's hard to improve over the OEM configuration.

G


There are many threads here on the page that support the sage advice to leave wheel/tire diameter of diesel tow vehicles alone - or increase by no more than 5% over stock.

The ECM, TCM, gear ratio, brake hardware, etc. all work together to create a fantastic towing machine under a variety of altitudes, temperatures, loads, etc. In short, the truck that rolls out of the factory is nearly IDEAL. Changing tire size drastically requires rethinking all of the above, which is unlikely or $$$ impractical to do.

...especially if you intend to tow heavy. ;)

[gary_lucas]

That is absolutely correct, and I can guarantee our first stop will be at a scale after leaving the dealership... I wonder if they have one actually.

To be honest after doing a pile of research and hearing from other people on this forum, I'm towing light compared to most. I'm just going to get the numbers and add airbags if I seem to need them.

G


I'm pretty sure that the published hitch weight of the 5th wheel is with an empty trailer. So the only way to know how much weight is in the bed of the truck is to road load it and then hit the scales. Am I right? If your weight on the hitch increases then your payload decreases in the truck. Keep in mind the max weight that the rear axle is rated at, you may have to lighten up the pin weight and leave some pots and pans home.
Denny

[DmaxMaverick]

That's all sounds good, the tires on the trailer are 15's,

So, not sure if I can get the 16's on the trailer, the 16's I've got are 265's, I'm assuming they'll be too big. But I'll check it out :)

Is it even possible to get bigger brakes on bigger wheels?

Gary

15's? Is this a 3 axle coach, like a toy hauler? If so, do whatever you have to do to get away from the 15's. There are NO good 15" tires for heavy trailers. NONE. Also, if it's a toy hauler, keep in mind you can't base your weight if it isn't loaded. All/most of the "toy" weight will be behind the trailer axles, which will unload the pin weight. Storage tank placement will also have a great affect. They're usually with fuel storage in the rear, with fresh/waste forward. 800# of fresh water going, and that much waste water returning, will have as much affect on pin weight as anything.

If it's a 2 axle coach with 15's, do whatever is necessary to change that. Change the hubs if you have to (most Dexter axles will interchange). 16" tires offers a large selection of 10-14 ply tires, much less expensive and much more durable LT tires (the preferred option, IMO). NOTHING from China, no matter what brand they are! (Goodyear Marathon, Carlisle, come to mind)

BTW......
My 2005 Mountaineer came new from the factory (dealer) with 235/85/16E tires (14K+, 3-slide, 36', aluminum upper frame). They are LT's, "Made in USA". After decades of replacing travel-trailer and 5th wheel tires every 1-3 years, for various reasons, these are still on, and still in very good condition. We're getting close to trading up, but this is the best coach we've had. Previously, we've never had one for more than about 5 years. We're 8 years into this one, and will be sad to let it go, but it will go, with the original tires! I can't say that about any previous coach we've had, or heard of.

[gary_lucas]

That's good info, didn't realize that 15's sucked so badly, I'll keep an eye out for a decent deal on LT tires.

I may even buy new truck tires for the truck and put the old ones on the trailer like the other guy suggested. Or maby not, those tires are hercules, but getting old. Not sure how long they were on the truck for... They came from the previous owner.

It's a shorter 31" (fox mountain 275bhs) 5th wheel, not a toy hauler so we won't be putting anything particularly heavy in it.

G


15's? Is this a 3 axle coach, like a toy hauler? If so, do whatever you have to do to get away from the 15's. There are NO good 15" tires for heavy trailers. NONE. Also, if it's a toy hauler, keep in mind you can't base your weight if it isn't loaded. All/most of the "toy" weight will be behind the trailer axles, which will unload the pin weight. Storage tank placement will also have a great affect. They're usually with fuel storage in the rear, with fresh/waste forward. 800# of fresh water going, and that much waste water returning, will have as much affect on pin weight as anything.

If it's a 2 axle coach with 15's, do whatever is necessary to change that. Change the hubs if you have to (most Dexter axles will interchange). 16" tires offers a large selection of 10-14 ply tires, much less expensive and much more durable LT tires (the preferred option, IMO). NOTHING from China, no matter what brand they are! (Goodyear Marathon, Carlisle, come to mind)

BTW......
My 2005 Mountaineer came new from the factory (dealer) with 235/85/16E tires (14K+, 3-slide, 36', aluminum upper frame). They are LT's, "Made in USA". After decades of replacing travel-trailer and 5th wheel tires every 1-3 years, for various reasons, these are still on, and still in very good condition. We're getting close to trading up, but this is the best coach we've had. Previously, we've never had one for more than about 5 years. We're 8 years into this one, and will be sad to let it go, but it will go, with the original tires! I can't say that about any previous coach we've had, or heard of.

[Yukon6.2]

Hi Gary
If the wheels are 6 hole you can get 16" wheels in 6 hole.
I just won a trailer in a bid,was going to flip it,but now i'm goig to keep it to tow behind the dump truck for my bobcat,anyhow it's on 6 hole 15",it's got fenders so i think i'm going to a 225 75 16,no room for any bigger tires,but if you have room go for the 235/75-16 in a LT.the 265's you have would probly be to wide for the trailer.
Thomas

[Grayfox]

FYI

http://changingears.com/rv-sec-tow-vehicle-sizing.shtml

Please do the math. This can be a very enlightening exercise.

This site should give you Trailer Life Tow capacities and the Cat Scale locator

[gary_lucas]

Yah, I've run all those numbers.

Thanks for the link though, I'm bookmarking it.

Sadly the link to the 2500hd GMC page towing values is broken :(

Not that I need it, I have the original owners manual and etc. I'll be stopping at a scale shortly after I pick up the trailer this Friday to get final numbers.

Thanks allot :)


FYI

http://changingears.com/rv-sec-tow-vehicle-sizing.shtml

Please do the math. This can be a very enlightening exercise.

This site should give you Trailer Life Tow capacities and the Cat Scale locator

[gary_lucas]

So, got the 5th wheel.

It squats just a little in the back, I don't even know if people would notice, the rear wheel well is probably even or just slightly lower than the rear wheel well.

My mechanic strongly suggested having the spring packs reworked to get back up a little, considering that. He said he has a connection with a place that specializes in building / modifying spring packs.

Otherwise it's air bags or super springs, probably going to wait for a bit on those as I don't think we'll be doing much highway traveling this year, mostly just local stuff while I wrap my mind around driving with it.

I put it on the scales and the axles are:
FA: 4510
RA: 5412
Total: 9922

Truck GVWR is unfortunately 9200 if I remember correctly, I'll check the sticker on the door tomorrow to confirm. it's running the 265's so I'm under all the axle ratings.

[Waynec1957]

So, got the 5th wheel.

It squats just a little in the back, I don't even know if people would notice, the rear wheel well is probably even or just slightly lower than the rear wheel well.

My mechanic strongly suggested having the spring packs reworked to get back up a little, considering that. He said he has a connection with a place that specializes in building / modifying spring packs.

Otherwise it's air bags or super springs, probably going to wait for a bit on those as I don't think we'll be doing much highway traveling this year, mostly just local stuff while I wrap my mind around driving with it.

I put it on the scales and the axles are:
FA: 4510
RA: 5412
Total: 9922

Truck GVWR is unfortunately 9200 if I remember correctly, I'll check the sticker on the door tomorrow to confirm. it's running the 265's so I'm under all the axle ratings.


I'm a little late to the discussion but I was wondering how this worked out. We're in the process of looking for a new TT now. We've more or less ruled out 5th wheels because on everything we like the kingpin weight plus the hitch and all the other "stuff" in the truck puts us at or over the rated payload (just over 3,000 lbs). Add up me, the other half, a couple grandkids, 36 gal. of diesel, 200 lb. hitch, and 2,000 lb. kingpin and it doesn't take long to eat that payload up.

For what it's worth, and I'm no expert on anything, I always try to pay attention to the upper limits of any piece of equipment I use. Under normal use, I try to leave myself a little cushion knowing there may be times I have to ask a little more of the equipment. If I'm always operating maxed out, I may not have what I need when that need arises.

One of the reasons I went to the 2500hd Duramax was because pulling the TT we have (much less a bigger one) with the old 1/2 ton gasser taxed me and the truck more than I was comfortable with.

[gimpyhauler]

Yesterday I drove about 500 miles round trip to get my tractor. South central Oregon is mostly flat. Driving to the dealer, I got 18+mpg @ 60mph on cruise with only very short stretches being 3% grade. Hooked up to a 22K 20ft gooseneck with my new/used John Deere 210SL tractor with a full 25gal tank. Just under 9500# on the tractor alone. Tool box, 34gals in the tank and 20gals in my transfer tank. Wife and I with twice the necessary chains and binders. Got 8mpg loaded. Never before needed my turbo for just a 2% grade. Got 13mpg after unloading the tractor and returning the trailer to the dealer. Thankfully no problems but I was impressed and happy to be done for the day. :o

[gary_lucas]

I'm a little late to the discussion but I was wondering how this worked out. We're in the process of looking for a new TT now. We've more or less ruled out 5th wheels because on everything we like the kingpin weight plus the hitch and all the other "stuff" in the truck puts us at or over the rated payload (just over 3,000 lbs). Add up me, the other half, a couple grandkids, 36 gal. of diesel, 200 lb. hitch, and 2,000 lb. kingpin and it doesn't take long to eat that payload up.

For what it's worth, and I'm no expert on anything, I always try to pay attention to the upper limits of any piece of equipment I use. Under normal use, I try to leave myself a little cushion knowing there may be times I have to ask a little more of the equipment. If I'm always operating maxed out, I may not have what I need when that need arises.

One of the reasons I went to the 2500hd Duramax was because pulling the TT we have (much less a bigger one) with the old 1/2 ton gasser taxed me and the truck more than I was comfortable with.

To be honest I never followed up. After driving it all for awhile I found it was pretty comfortable... Can't be bothered to spend money on stuff I don't need...

I think the truck squats down about 1-1.5" so really nothing to worry about.

[trucker582]

Im wondering if the truck is built to deliver the towing capicity and gut to haul my late model 38' 5th wheel. 2axle. Weight is ok, speed isnt an issue since 65 mph will be my max. 4:10 gears, 4180 auto. Pmd relocated, airbox stock but opened, modded. 4"exhaust ordered. Im not used to the "smaller" diesel, as I tow aaa with a duromax/allison, and otr semi. Dont want to go overboard "modifing" something that wont go the distance.

[sctrailrider]

Not going to be anywhere close to any dmax, cummins, newer type ....

These are fuel mizzer motors, not direct injected, they will never work like the newer diesels but will do the job if you know their limits...