I pulled the TT the first time and tried to use the od and seemed to down shift too much at 65-70. So I ran it out of od at 2800rpm most of the trip. The truck ran the hills awsome but should I run these rpm all the time? Too many rolling hills here to run od with 7500lbs behind me, maybe when I run down thru Ill. I will try running od. Still managed to get 8-9mpg towing though.

 

I tow without OD also. I only manage to get 7 or 7.5 while towing though. I don't think there's a problem towing at 2800. I drove straight to RI from VA last summer towing a 7200lbs. TT.

 

2800 RPM is nothing for a gas motor. My 6.0 PSD even had to make those types of RPM when hauling my camper up long steep grades. I think you will have people telling you our V10s can haul at 4000 RPM for extended periods with no problems. Take care, Wrench.

 

I pulled my TT cross country at 3000 rpm! Maybe I should slow down

 

Thanks, I thought the engine sounded real good (sweet spot)at that rpm and speed. I'll run her there then...... I am used to my diesel suburban running at 2200-2400 in od so something to get used to.

 

Depending on where you're towing, you'll be having to think, and use your God-given propensity to fool with stuff. Like the OD button, the gearshift lever, all sorts of cool, manly things. If I remember you have 3.73 gears like I do, so here's the drill. While towing on flat level ground you keep that big, bad boy X in OD, as long as it isn't hunting in and out of gear. Slight downhills, straights with no wind, all those are prime candidates for OD towing. And you'll look over at the missus and say; "boy she tows like a big dog in OD huh honey?" (she'll have no idea what you're talking about, which is preferred) As you start to gain altitude or pull a grade, before your tranny kicks down you'll hit the button, locking out OD. You'll then look over and say; "these E40D are great transmissions but with that direct drive sometimes they'll hunt, so you have to watch the ECM and not let it kick down too often". (she'll be looking at you in awe and semi-wonder by now, so you need to keep pressing home the point that this is all mysterious, deep, 'man-stuff') Trust me, you can work this for hundreds of miles, your young lovely will look at you with new appreciation. The V-10 will run at 3 grand, 4 grand heck even 5 grand all day. But you control your own destiny Luke, use the force, shift manually before it starts to hunt, you'll gain two-fold, peace, Ken