OK so some may remember not quite two years ago I started a V-10 vs 6.0 thread that had a few not so pleasant replies but mostly great info and infacto information. I ended up buy the '04 dually.

Well as the title to this thread would have indicate I've done another change. I traded the '04 King Ranch dually for an '07 250 Lariat Crew Short-bed. It happens to be lifted, 6" with 37's (also, cold air intake, 5" turbo back w/a cat). Real quick I will back up just to say that after all the talk about the 6.0L I am sold on it, its a great engine as many of you told me back then, its quick and powerful just out of the box. I will say however that the '07 runs better than did the '04 but it only has 66K on it.

Back on Subject - I do tow a bit (bout 8K) and I'm wondering if any of you fellow 6.0'ers tow with a lifted rig? My truck has, I assume, 3:73 gears. I love the way it looks, feels and drives and for sure I have a very commanding view of the road but would for sure like to get back a bit of the power loss and fuel mileage.

So has any of you 6.0'ers done a gear change and what was your results?

 

No one has re-geared their 6L? Hmmm I would have thought a number of you guys probably have.

 

A lot of lifted guys do. You won't gain any miliage until you go back to stock tire size.

 

Thanks for the reply... Even with a gear change to off set the tire size? Interesting!

 

Your only offsetting the power lost. Lower gears = higher RPM range = more fuel burned.

 

Im running 35's havent had any real issues and mpgs on the road are pretty close to the same. Havent regeared just calibrated the speedo

 

For sure... But what about - Stock gears + Bigger tires = lower RPM range + harder to get going (so to speak) = more fuel burned

Hence - Lower gears + big tires = stock RPM range = regular fuel burned??

Absolutely not downing your theory in the least, simply going through all possibilities.

By-the-way 79 how do you like the electric T-Case? I think I'd prefer the 'ole shift it in myself, less to go wrong I guess. Mine goes into Low when it feels like it (with electric) and not the rest of the time,

 

I hate the esof hubs the tcase has worked flawlessly. 4l is about useless in a diesel

 

Well you know it was awesome in my '99 and in my '04 but this one just seems gut less. I'm actually going to have it checked out soon. It seems like the turbo really has to spool up for it to do anything in Low but my other two didn't do that at all.

I had a number of times back home in the snow when towing my Jeep that the 4L saved my bacon, but I'm not sure this one would

 

Howdy,


I have a 2005 F350 Dually 4x4 with stock wheels and tires (4.10:1 rear) and it gets about 16-17 on the highway.

I have thought about lifting it and going to bigger tires and wheels but most tire dealers are leery about big wheels/tires on duallys.......larger diameter tires will be like taller gears and will reduce the towing capability.

I'm probably just going to stay with the OEM 17" wheels and stock size tires.


Regards,



Rick

 

Im not sure how much actual fuel mileage you lose going with a larger tire but some of the perceived loss in mileage is due to the speedo calibration being off because the tire covers more ground per revolution. You would however get your low end pulling power back with regearing and will get the gear ratio closer to stock and the speedo will be more accurate.

 

That is a lucid, intelligent, well thought-out objection ~ Uh I mean response...

That actually just made a light turn on in my head... With the Speed-o Off would that make the computer read the MPG wrong also? That is what I am basing my MPG on.

Rick,
I put a leveling kit on my King Ranch Dually and ran 285/75R16's on it which is a 33X11 tire and towed my Jeep all over and never had an issue with it towing wise, but yes my MPG's were lower. Towing I got 11 and on flat terrain highway I got 13.

 

Yes sir it absolutely would.

 

Now that is interesting... So I would imagine that it would make it read Lower since the tires, as you mentioned, are covering more ground and you are actually traveling faster than the speedo shows...

 

That is correct.