hi iam new to forum really confused on how much weight i can pull with my truck 2008 f350 srw 5.4motor 3:73rear end 10600 gvwr package 142 wheel base and 5 speed auto transmission looking to tow fifth trailer that weights 8400# dry any help would be appreciated

 

4x4?Cab style? its between 9200 and 10100 depending on options!

 

supercab fx4

 

Then it is 9400 lbs BUT you have a 16,000 GCWR. Assume you load your trailer with about 1000 lbs of stuff that brings it to 9400. The truck then cannot weigh more than 6600 lbs with cargo and people! That makes it near impossible to get the truck to 6600 lbs. SO with your current setup the trailer is to big for the truck!

 

So need bigger motor or different cab style Iam about two days from buying unit any suggestions would be great

 

You are missing a couple important pieces of information. You need to know how much the trailer will weigh when it's loaded, and also you need to know the pin weight.

 

laoded can only assume 9400 and pin weight 1450

 

The biggest thing that's limiting you is the combination of the 5.4 and 3.73 gears. If you had 4.10 or 4.30 gears, your capacity would go up significantly.

 

would i be able to tow it on some short trips till i get another truck and what would suggest for truck i realize hill will be huge problem

 

regear both axles to 4.56 and it'll do anything you ever ask of it

 

+1 on this.

No need to buy a whole new truck, just regear the truck you have. With 4.56 or even 4.30 gears you will have no problem.

The truck will pull it now, but it's really going to be working with the 3.73 gears. I'm guessing the 1400 lbs pin weight is dry so it will go up a little when loaded, but it will be no problem on an F-350.

 

May I suggest Firestone air bags, I pull a 37' Montana about 2000 pin weight with a similar setup. Without the air bags you will ride around on the overload springs, giving you a jerky feeling over bumps. I have a F350 5.4 CC short bed, 4.10 gears.

 

Well, as a former owner of a 5.4L (granted it was the older 2V), I can say that yes, the 5.4L will pull it. I even had 4.30 gears on mine (2WD only). My 5th wheel was "supposed" to weigh in dry at 8400 pounds (I later learned it was closer to 9100). My GVWR for the trailer is 11,600. I knew two things. I wouldn't be taking long trips with this combo, especially to anywhere that had anything resembling a hill or mountain. And, I would be looking for a new truck. This really became apparent after the first tow. Yes, the 5.4L towed it, and actually felt pretty good. But on the freeway overpasses, it struggled. It also struggled to get up to speed. It started out great, up to about 30mph, then struggled to get up to speed. Overdrive is out of the question, though with the 2008, you would have Tow/Haul which would help considerably.

The bottom line...I loved my 5.4L. But it was just not the right tool for the job. I got the 6.4L and I was a much happier camper. For sure you are beyond your weight limits in your current setup. With appropriate gearing, you would do better, but you still will not get the grunt (torque) provided by the diesel. The V-10 would be a good alternative, if you could find one. But you will definitely be happier with the diesel.

 

My V10 pulls greatafter switching form the 3.73's to the 4.30 gears. Your 5.4L would do fine with new gears and the cost is affordable. I paid $1,200 a couple of years ago. No need to buy a new truck.

 

A gear change would definitely do the trick short term or just on short trips, it will just be slow going up hills and such. Long trips, however, will be a real core I would think. Some times there is no substitute for cubes when it comes to towing.

Have you looked at any performance modifications for you motor? I'm not familiar with the 5.4 so I don't know what its capable of but I'm sure others here do. I have an 02 F 350 with a 7.3 that I haul with commercially and I wouldn't use any thing else. I only gave $5500 for the truck and just had put the nickel and dime stuff into it.