Ok, I know how to set the Factory installed controller no problem. Just how much or what gain amount should I bee looking for as the "Down the Road" setting? Should the brakes lock up? Grab or how much Grab should I be looking for?

 

The trailer brakes should never lock up on pavement, and probably not even in most gravel. Unless you use the manual slide that is.
The gain setting varies a lot, but you shouldn't be able to feel the trailer "pulling" the truck when stopping and you also shouldn't feel the trailer "pushing" either. Don't focus on the number Just use whatever gives you that "everything stopping at once" kind of feeling.

Sorry that's so subjective, but I don't know a better way to explain it.

 

I don't concern myself too much with the numbers of settings either. I set mine to I don't know the trailer is back there when stopping. Basically the trailer brakes are stopping the trailer ad the truck brakes stop the truck - no push/no pull.

 

If you aren't sure what we mean, do a little city driving with it set to 10, and then again with it set to 0. The difference should be obvious there, so just dial it into the middle somewhere until you can't feel either of those two extremes.

I often mess around with the settings on a trip.

 

You should be setting it so when towing... the truck feels when stopping like there isnt a trailer behind you.
If the trailer is pulling you when stopping..to much trailer brake.
Trailer pushing...to little trailer brake.
You have to play around ...but after some seat time its just a feel thing.

 

One thing which needs to be considered as well is your weight and balance. If you are pulling a cargo trailer for work and you're constantly changing the load you'll have to adjust your settings accordingly. My work trailer is constantly changing weight and I have to balance the brakes every time to get the sweet spot the others are talking about. If you're pulling a RV with a fairly constant weight you'll be able to leave the setting where it is for the most part.