I am looking to buy a 4x4 supercrew with 4.6 engine. What rearend do I need for for towing with this vehicle? I will be towing about 6500 lbs. Thanks for your replies!

 

I think your only choice is 3.55. A 4.6L supercrew 4x4 (the heaviest f150 available) plus a 6500 lb trailer is gonna be a slug IMO. I think you should opt for the 5.4L. If you tow that alot, look into a 250 crew cab maybe? The SD's have lots of ratio choices. You can get a 4.30 gear in a 250. You could get a 3.73 with the 7700 package, but I don't think you can do that on a screw.

 

manford,
listen to what 2000 is telling you. 6500 lbs. is way too much for a f150 to be hauling. i unknowingly hauled 7500 lbs. of lumber + the trailer last winter in the snow for 50 miles on hilly backroads. i made it, but i couldn't get over 40, the trailer wagged on me. yep, if i had known i would have taken my bigger tandem axle. but, i will not get into that situation again. i was crazy for pulling that much. i didn't know til we weighed the load. i could tell it was heavy, but no idea how much. my buddy said it should weigh around 4000, he was a little off. lol. anyway, to make a long story less long. seriously consider a 250 minimum. if i were going to haul 6500 on a regular basis i'd probably look into a 350. either one will pull it, but the 350 will do it for a lot longer. good luck, Rich.

 

I don't know what the ratings are on the '02 SCREW. But I don't think it would be more than my SCAB and even though I could do it based on the book, I am sure it would be my truck to death f I did it with any regularity. I feel comfortable with 4000-5000Lb occaisionally and 2000-2500 every weekend. If I were going to tow 7000lb more than once I would definitely get a 250SD. Plus you get better rear end options. You would need 4.1 or better in a 150 and it isn't available. Only problem with the 250 is which engine, 5.4 (not enough) V10(gas hog), PSD(choice but very pricey). If you finance it over 5 years it isn't that much more.

Have fun.

 

If you are hauling at highway speeds a f250 4x2 with the big v-8 5.4L and 4.30? limited slip rearend will be more than enough for a small load of 7000lb. If your doing some back road, farming or construction work and have no disire to go highway speed the f250 setup can easily pull over 16000 lb.

Dont tell me it cant and wont because this is what i do in the summer. Ive pulled a gooseneck, with 8 hay bales on it, pulling a wagon ,with 8 hay bales on it too. each bale weights approx. 1200-1800lb. now add trailer and wagon weight plus steel flatbed, gooseneck hitch made of 3/4 inch steel plate, bumper hitch made in similar fashion, and homemade duel rear end with 4 8 ply tires and your way above the 16000 lb i stated above. the only reason you cant go highway speed is the wagon. With just the gooseneck loaded we can go 65 no problem. thats still over 8000 very easily.

just my penny of thought on the matter

 

Further support as to why the Zone Representatives take a suspicious look at warranty claims (and why it's wise to avoid buying used farm-trucks).

Manford, some other details come into play -- such as the wind-load of your intended load (is it a camper, or a flat-bed with a couple of motorcycles); will you be pulling up-hill at high altitutes; will the trailer have adequate brakes; at what speeds will you tow; what percentage of the time will you be towing; will all the weight be in the trailer; 5th wheel or pintle or load-equalizing or plain hitch, etc.

To answer your question, however, you need to decide at what engine RPM you wish to see at the given road speed of interest.

For example, if you wish to be in the 'torque curve' (~2500 RPM with the 5.4) at 65, you'd be at the 3.55 ratio with normal tires.

If you want to be closer to the Horsepower peak at that speed, you'd need something approaching 4.56:1.

Someone has posted a neat spreadsheet for calculating the RPM at various tire sizes elsewhere on this board. Do a quick search.

It wasn't too long ago that non-Overdrive transmissions were used on pick-up trucks -- and engines were treated to 4.56:1 ratios for zillions of hours and over a hundred thousand miles. The driveability while towing was very pleasing -- and/but the gas mileage sucked. That's why everything now has an Overdrive transmission. If you want the performance that is available from your (any) engine, you get it thru gearing.


Parting thought: While indeed a dog can be taught to walk on its hind legs, it is unreasonable to expect that it can do it all of the time -- same goes for overloading trucks.

 

I have a 31 trailer. Its 5600 Lbs dry weight and 7000 Lbs gross. I have towed it many thousands of miles with no problems using my 98 supercab with the 4.6L. I did work it pretty hard though. I now have a Supercrew with the 5.4L and love the way it tows with ease. I have towed about 3000KM with it so far through Ontario, New York and Pennsylvania.

I think some of the talk of you need a Superduty is overkill but this all depends on how much you tow and where etc. But go for the 5.4L and the 3.55 rearend is the one that comes with the Supercrew towing package. My truck with 5.4 is rated for 8000Lb towing. Take off 300Lbs if its a 4x4 and the 17" wheels also loose another 500lbs. I wanted maximun towing with a Supercrew which meant no 4x4 and no 17" wheels and the 5.4L with 3.55 rearend. My 98 Supercab was rated for 7000lb with the 4.6L but I think this will be slight less than that (300Lb) for the Supercrew to account for the extra cab weight. My guess is the truck you are looking at with 4.6L and 4x4 would have a towing cap. of 6300Lb.

Keep in mind that when calculating your tow weight you must also consider passengers in the truck, luggage, cargo, fuel, water etc.

 

manford. yor getting alot of GOOD advise and some BAD.
In your case you want a screw, but with a 4.6L engine, that I would stay away from, at least get a 5.4L.
I don't know if Ford will be coming out with a 7700# screw or not, but that would be your ticket.

A rule of thumb on towing, take your trucks tow rating and X by 80%, some use 75%.
I pulled a 31' TT with my 97 S/C, but had air bags and Reese hookup, my total# was 6200#s, no water in tanks and propane tanks M/T.
I now pull a 5000# boat and a 25' FeatherLight enclosed car carrier. Believe me, the boat pulls harder than any of them, no torsion bars and surge brakes.
Hook up with a good dealer, and he'll give you the straight poop..
Look at my Sig, and that's why I have 3:73 rears.
Good Luck