My wife and I own a 2003 Mercury Mountaineer, in addition to our 1998 F150.
I am interested in towing a boat weighing about 4,000# with the Mountaineer. It is a 4.0L (6 cylinder) with a 5 speed auto trans. I did not get the optional tow pkg on the SUV. It came with a Class II Hitch (1 1/4" receiver) and a flat 4 plug. With this configuration, it is limited to a tow rating of 3,500#. If I had opted for the tow pkg, it would be rated to tow 5,000#.
If I switch to a class III hitch (2" receiver) and add a trans cooler, will this be enough to increase the tow rating to 5,000#? I am OK with the current wiring and I understand that I should not use O/D while towing. This SUV is really geared high in O/D.
The only thing I think I would be lacking is the 'Limited Slip' Differential.
Please let me know your thoughts. I really want to hear from those of you who own, or have owned, this type of SUV. The Explorer and the Mountainerr are basically the same SUV. The trim level and appearance are the only differences.
Thank you.

 

i would tow much more than the truck weighs unless the trailer has electric brakes

 

In "theory" you should be able to add the necessary "tow package" parts to a non tow package equipped vehicle and claim to the higher tow ratings....

I think the limiting factor in your case is your Class 2 hitch and that it's only rated for a #3500 trailer.

Now, you can't just slap on a Class 3 hitch with a #5000 rating and call it good.... Like you mentioned, you will need to add the aux trans cooler for sure. Some tow packages include what's called "super engine cooling" and usually consists of a larger core rad. Sometimes this also includes an engine oil cooler as well.....

Might need to find a web site that lists what the different packages included for your year truck??

"Most" boat trailers will have 'surge brakes' on them. "Most" states also have some law that says '...any trailer weighing in excess of 2000 lbs must have brakes on it's axle(s)...'.

Does the Mountaineer have low range?? Might make for an interesting time pulling the boat out of the water if the boat ramp is unusually steep and/or slimy....... Open diffs won't help either....

You might not want to go much heavier then the #4000 you mentioned however.... If that's the "dry" weight of the boat alone, then you also have to add in the weight of the trailer and any 'stuff' you put in the boat too..... The heavier it is, the harder it will be to pull out of the water....

Good luck!

Mitch

 

I think I would lean towards your F150 with the 4.6 V8 for the boat tow.
that open rear axle will give you a fit you are only 2 wheel drive on the boat ramps.