Originally Posted by will40
... Trailer is 4950lbs Expy in at 7350lbs, the combination is rated at 12100lbs max from Ford.
...***Finally my question- Do I need to upgrade to a larger SUV (excursion or Suburban 2500) or will my current (well loved) Expy be enough. Expy is paid for and has such low kms it would be a shame to sell but my family's well being is priority #1.
Your Expy has a tow rating of up to 6,000 pounds, so the 5,000 pound trailer should be okay.
The problem with an SUV is you can either haul a bunch of people, or tow a 5,000 pound trailer, but not both at the same time without being overloaded.
Here's what I would do in your shoes.
Heat is the killer of towing vehicles, so get rid of the excess heat in the motor oil, coolant and tranny fluid.
1. Upgrade the oil-to-air (OTA) tranny cooler to the biggest one that will fit. If it doesn't already have and OTA tranny cooler and gets by with only the oil-to-water (OTW) cooler in the bottom of the radiator, then I would add the biggest OTA tranny cooler that will fit in front of the radiator.
2. Upgrade the radiator to the one that came with the HD tow pkg. Any sharp Ford parts person can tell you what you need.
3. Add an oil cooler. Use a "sandwich" adapter between the oil filter and the block as your source for the hot oil, then place the heat exchanger (oil cooler) anywhere it will fit under the truck. Etrailer.com has several, and one probably has the correct threads to fit your rig:
Engine Oil Coolers Sandwich Adapter Accessories and Parts | etrailer.com
That should take care of the heat problems. Next is hitch adjustment. You need several weights to dial in your hitch.
1. Wet and loaded trailer tongue (hitch) weight or TW. Two ways to get that. Easiest is with a tongue weight scale. But you can also weigh the Expy with and without the trailer tied on. Add the two SUV axle weights with the trailer tied on and subtract the two SUV axle weights without the trailer. The difference is hitch weight.
2. Weight on the two Expy axles with the trailer but without the WD hitch spring bars tightened.
3. Weight on the two Expy axles with the WD hitch spring bars tightened
Your goal is to remove about one half of the hitch weight from the rear axle and distribute it to the front axle and trailer axles when the spring bars are tightened.
For example, if the tongue weight of the wet and loaded TT is 650 pounds, the WD hitch should leave about 325 pounds of hitch weight on the rear axle, transfer about 160 pounds to the front axle of the Expy, and transfer another 160 pounds to the trailer axles. Those are round numbers, so plus or minus about 25 pounds is probably okay.
If that's not happening, then adjust the hitch per Reese instructions until you get it close to right.
Two ways to adjust the hitch. Simple is to tighten the spring bars one link more or less. That will transfer more or less weight off the rear axle. If that does the job, then you're done. But if too much weight is transferred to the front axle or to the trailer axles, then you need to change the tilt of the hitch ball until you get about the same weight transferred to the front axle and the trailer axles, with the spring bars tightened just enough to keep about half the total hitch weight on the rear axle.