Hello, I'm new to this forum. I have a 2008 Super Duty, 6.4 liter Diesel, F250, crew cab, long bed.

This truck has the 10,000 lb GVWR package. Has airbags, 5,000 pound rating each.

3.55 ratio limited slip axle. 35 inch ProComp Extreme tires on 18-inch rims. (My realized gear ratio over stock tire size should be closer to 3.9.)

So... with those details, I wonder how much 5th wheel I can pull safely?

I live in So Cal, drive flat roads to the desert. Of course the RV dealer tells me I can pull 17,000 pounds of trailer with this truck. This is not a daily haul, only now and then.

So... the question is, do I need a bigger truck? I sure as heck don't want a smaller coach! This one has three axles, and maxes out fully "wet" at 18,000 pounds.

Am I a disaster waiting to happen with this setup?

Seriously, I don't want to do anything stupid. I will get a new 2011 F350 dually if that is the best way to go. My coach is a toy hauler, triple axle, 41 feet long. I don't have it yet, but will.

Any thoughts? I know bigger is better. But with my current setup, can I "get by okay" for now, until I can get the bigger truck? Heck, I'd get a Sport Chassis by Freightliner if I could.

Thanks for any input.

 

Some RV salesmen are just morons for putting people on the road with more trailer than they can safely haul. Too bad it happens all the time.

The short answer to your question, if the specs I'm reading are correct, is yes, you will need a bigger truck. You are almost 3000# over the towing limit at 18,000#.

The '08 F250 you have is only rated for 15,200#. You would have to be in an F450 in the '08 model year to safely tow 18,000#.

http://turbodieselforums.com/towing.pdf

 

How much is the pin weight?

I would not worry about hauling it if its not putting too much weight on the trucks axle.

 

you've got this backwards.

taller tires will reduce your realized gear ratio. I believe you'll be closer to 3.2

 

I have lots of miles towing a fifth wheel trailer weighing in between 15-17K on a F250 ('08 and '11). On the 6.4 I had 3.73 and stock tires on the 18" rims.

1. The 3.55 (3.2 you are at) is going to be very tough. The 6.4 takes time to build the power and until you do you'll be going almost nowhere with 80% throttle and lots of torque converter slippage under heavy strain.

2. I tow a cargo trailer, triple 7K axle, 36' long and the center of gravity is very low, MUCH closer to the ground than an RV. I believe this to be the reason I can tow this heavy with an F250 comfortably. My trailer and load is very stable, unlike the RV trailer, which most all are not set up to have great towing manners, they are set up higher and axle placement/pin weight is secondary to floor planning and storage.

If I were you, I would get a dually, and I am not a fan of dually's, would never push one on anybody unless it were truly necessary. With a 6.7 '11 model I would suggest a 3.73 axle. I say this because after driving a 6.7 for a few months now I can say that the initial launch is stronger, 6sp tranny is better with weight off the line.

 

I tow a 14K high profile 5er with mine. F250 6.4 with 3.73 gears.

My concern would be pin wt going over the 6100 lbs rating of the rear axle and your tires reducing the gearing so that is ineffective.

I honestly think that you will be killing you and the truck in your current configuration.

 

I don't think u have a 3.55 axle.. 3.73 should be the lowest

whats the number on the door post (between driver side doors) tag, last row, under 'axle'..

as noted already, the 3.73 F250, Crew cab 5th wheel towing limit is 15,200. (4x4, 4x2 is 15,800) thats everything and everybody.

the pin weight is supposed to be 15-20% of the total.. so at 18000
thats 2700-3600 lbs.. I don't think you have the tire capacity to carry this on an SRW.

that tag will also give u axle weight ratings. take your truck to a truck stop weigh scale, and for $9 (8.50 here in texas) you will get actual weights.

can the truck chassis handle it.. probably, is it safe... no. rear tires have a limit.

sam

 

the only 250 configuration that would fit 2,700# under GVWR is a regular cab, and that doesn't come anywhere near the RAWR.

The tires (assuming a load index of 121) should be good for 3,200# each

 

Don't forget, that 3200#'s is at max tire inflation ( Load E, 70-80 psi)

 

right, so thats 6400 - existing weight (get actuals) guess 3400, means 3000 total additional capacity (fuel, cargo, people) and we need 2700 minimum.. so its unlikely to be sufficient.

My Dually has a 9000lb RAWR. and empty weight of 3600 lbs. so I can add 5400lbs.

(how this is called a 1 ton, with 2.5 ton carrying capacity confuses me)

Sam

 

by guessing 3,400#, you're projecting more than half of the weight of the entire pickup onto the rear axle.

For instance, a Regular Cab Super Duty has a curb weight of 5,900#. Most of that weight is in front (engine, cab), and the rear gets a big empty box. Making a quick conservative guess of 65% front and 35% rear, you get 2,065# on the rear, which allows for over 4,000# of cargo to be added before busting tire ratings.

My rear axle has a rating of 5,892# which is less than the tires allow.

 

My opinion (this and $10 will get you a coffee at starbucks):

Quite a bit too much trailer for this truck. I don't think it will be an "immediate disaster". It will do it marginally safely at least a few times, but this kind of abuse will result in premature wear and eventual failures. Some of the items being overtaxed enough to be a concern to me would be the transmission, rear tires and wheels, rear axle, and cooling system. And the big tires and poor gearing are really going to try your acceleration (and hill climbing) patience.

Keep in mind, all the "ratings" are best case scenarios. The truck capacity ratings are with absolutely no options, passengers, cargo, hitches, etc. Trailer dry weight is with absolutely nothing in it. Most trailers are at least 10 - 20% over their claimed dry weight before you put a thing in it. Batteries, water, propane, toys, dishes, food, adult beverages, it all adds up. The majority of folks find they are very near or even over the MAX loaded capacity of the trailer once they get it loaded up and drive over a scale. Especially with toy haulers. In talking to folks with triple axle 5ers hauling at least a couple/few quads, most found themselves at over 20K (based on scales) when fully loaded up. The weight adds up so fast....

Something to keep in mind: The 3 axle toy haulers are "weight police" magnets.... Many (most?) are grossly overweight and LEO's know that. They are much more likely to get pulled over and escorted to a weigh station than most rigs. An F250 with triple? Easy target. F450 or F550? Not so much.

 

Thanks everyone.

A lot of food for thought here. I think I'll simply go with the 2011 F450 4x4 dually. It's not that much more expensive than a 350, really, and rated at 24,400 pounds max loaded trailer weight for 5th wheel with axle ratio of 4.30. Could be overkill, but why worry about anything on the road if you don't have to? Plus, if cops are looking for 3 axle trailers being pulled by F250 and escort me to the scales, I'll be wishing I hadn't done it.

Good advice. This forum is excellent with the rapid response to questions.

 

That would do the trick! Good choice and post pics when you bring her home.

 

To h3ll with all of the guessing... load the truck with everything u plan on carrying (people, pets, fuel, ect). then find a truck scale & weight it. preferrably a scale that will give you front & rear axle weights. subtract those weights from the gawr for your truck - now you'll know what capacity you can drop in the bed (tounge weight).

me... if I were carrying that weight & length, I'd want a dully. its not a matter if it will pull it (that's the easy part), its a matter of controlling it and stopping it.