What setting??

[vadave]

Should I use the 87 Perf. or the 87 Tow? Will be on interstate 300 mi with 1000 lbs in bed. The interstate has some large long grades (I-64 through WV.)
I get much better mileage with 87 pref. but tow seems easier on the hills.

What are your opinions?

Dave

[Longshot270]

You can use either tune. The limit for the performance tunes are usually around 2500#s so you could still use it. You might get slightly better mileage with the tow tune though.