I have a 97 f150xlt super cab with 4.6 engine and 3.08 axle ratio. I looked at the specs on the ford web site and it states that the max trailer weight for my truck is 2000 lbs. But it also lists the gross combined weight rating (gcwr) as 10,000 lbs.

Now it was my understanding that gcwr - vehicle weight = max weight of trailer. If this is the case, I should be able to pull a trailer of around 5700 lbs since my truck weighs 4300 lbs.

Why does ford limit the trailer weight to 2000 lbs and then state that the gcwr is 10000 lbs? It doesn't make sense. Is it something about the 3.08 gears?

The reason I'm so concerned with this is I'm getting ready to purchase a boat that weighs around 3500 lbs with trailer. I would have thought (just by gut feeling) that a truck of this size and weight would have no problem with this size trailer.

Should I see about changing the rear axle gears or just wait and see how it does with this weight before I mess with anything? Does anyone know why ford would rate this trucks trailer towing so low? After all, this is a very heavy truck with a v8 engine? Why would ford make a full size truck that could only haul 2000 lbs?

 

You must have the manual transmission - the automatics are rated much higher for towing. IMO, Ford assumes you don't know how to tow with a manual, because they don't want to get stuck replacing clutches under warranty. So they put a superlow max tow weight on the 5 speeds.

Gear ratio does matter when towing heavy loads and is usually reflected in different tow ratings. It is easier on the engine and drivetrain with the 3.55 or 3.73 gears.

 

No, its an auto transmission. Look at this link

http://www.fleet.ford.com/downloads/...50_750_150.pdf

 

I think that chart must have a mistake. Check the 'sticky' trailer weight thread at the top of this forum. Raoul summarized the tow weight chart from his '99 F150 manual. The '99 Supercab 4.6 automatic tranny with 3.08 gears is rated at 5,500 pounds max trailer weight - that truck is virtually identical to yours.

FWIW, the change to 3.55 gears increases the max to 7,000 pounds for the '99.

 

I have a 01 and it had a 3:08 and was rated for 2000 lb trailer. I believe this is because they don't make a 3:08 with a tow pkg. No tranny cooler, and all the other goodies that make up the tow pkg. I put a 3:73 and a large after market cooler on it and most of the other stuff to make up the tow pkg. You would probably get by if you install a large tranny cooler and keep it in 3rd gear.

 

That's a good question. The current rating for that engine transmission axle combo is 5,600. I don't think the 97 had the electronic transmission. It would be interesting to see what transmission you have.

In your case, the limiting factor is the rear axle. That combo is not the best for pulling a trailer. 3,500# is when you start to know you have something back there. A trany cooler is important, and would be a must if you decide to buy the boat and pull it with the 3.08.

As far as the truck itself, it'll handle 3,500 with no problem. I've driven one of those trucks to Iowa and South Dakota loaded up. I recall it does a lot of shifting on hills. Put the tailer back there and you will see shifting on smaller hills.

How far are you towing, across the state, or to the local lake?

 

That's interesting about the electronic transmission. I didn't know the newer trucks had that. I'm not sure what type of auto transmission I have. I would be towing the boat 90% of the time just to local lakes, but would need to pull it 400-500 miles at least once a year.

suvdrvr, What kind of diference did you notice after you changed out your gears? Did it have a major effect on gas milage? Did you change them out yourself or have a shop do it? I'd be interested to hear your experience with this. If I do decide to change out my gears, what do you think about adding the limited slip while I'm at it?

Thanks.