3:73 to 4:30 on Excursion V-10

To each their own I guess ... Yes you would notice it towing. Your mpg will suffer a tad but who cares you didn't buy a V10 for mpg to start with. Generally I'm not a big fan of adding things to my rigs that have no resale value. Vehicles already depreciate too fast as it is and now you're going to drop $1500 and never see it again. Maybe in the future if you found the right buyer you can squeeze out a little extra but doubtful.

If it tows just fine now I wouldn't even bother. If towing is a problem then I would consider selling it and considering something new.