I need to change rides. I've got a 97 4.6 with a 1715 tuner. I mostly use 87 tow mode which I've been EXTREMELY happy with. The trans responded well and I can save a couple cents per gallon on the 87. Anyway, for vacations, I'll need to carry a slide-in camper and tow a 16' alum boat, so I've decided on an upgrade. My ? is which motor, a 5.4 or 6.8 and with an Xcal2 chip to help out with the FoMoCo shift patterns alone, if not for the occasional 93 octane program every once in a while to keep sane. I've read that the mileage is close until the 5.4 is towing and the mileage drops off significantly. I want to drive my truck and not shoot myself in the tank. Does a tune change things there for the 5.4? Any personal experiences with either of these packages would help. I didn't feel the need for an all out diesel setup for what I'm pulling.

 

If gas mileage is an issue, the 5.4L with 3.73 gears is a good bet. I've got an F150 with that motor and I tow an 8,300 lb 5th wheel behind it and occasionally add a very light weight boat behind that.

Before the truck was broken in and modified, I got poor mileage towing (6-8) but now I'm getting 9-10 mpg towing at around 62-65 mph. That is quite obviously the speed my rig tows best at.

City driving I'm getting just over 14 and on the highway I top 17 mpg.

If you mod the 5.4 properly, you can improve on factory mileage AND gain a fair portion of the power differential between it and the 6.8L.

The 6.8L has good power but I've heard bad things about the towing mileage. People talk about 6-8 mpg towing with that engine. The 6.0L diesel might be a better option, but then you get into the whole issue of guessing where diesel gas prices are going to settle out at.

You can get better towing information on rv.net in the tow vehicle forum.

Enjoy.

 

Thanks! I'll go over to RV.Net and check there also. This was one of my questions about tow vehicle, would I be able to beef up the F-150 to handle the slide in camper and the boat, seems so. I've heard great things about the 5.4 in the 150 platform as opposed to the 5.4 in the 250/350, vehicle weight wise. Can you list the mods on your truck as well as the year? It'll give me something to guage from. Thanks again.
Mike

 

Oh yeah, that also brings up the 7700 6 lug vehicles? Sorry for the direction change in this forum I'll take it over to another area.
Mike

 

Red97,

By far the smart choice is to go with the 5.4 - but remember that if you go with a pre-1999 5.4, you would also need to change PCM's, as they used the E4OD tranny instead of the 4R70W.

SO the smart tip is to swap in a 1999-2003 PI version of the 5.4 motor, and we can tune the PCM for that engine swap - and of course, you can do all the mods to the 5.4's that all the other 5.4 owners do as well. Though I would want to freshen up that tranny if you have not already done so, as you will be putting a significantly higher amount of torque and at at much lower rpms thru what is by now an 8 year old 4R70W - just FYI.