His gears probably were not up to the task. If I had to guess, I would say that likely he had 3.55's on it. I had 35's on my '01 4.6L with 4.56's. Never had an issue with the transmission. If a regear is going to be awhile after you plan to do the lift and tires, 6.2L and 4.10 gears will be your best bet to start out with. I agree with getting gears swapped no matter what. If you can get a used tuner cheap and get some custom tunes, that can hold you over till you have the $$$ for the gears. You are going to need a tune of some sort anyway to correct your speedometer for the larger tire size. Ideally, doing it all at once is best. $$$ and human impatience sometimes get in the way of that though.

 

Your friend made a big mistake in not regearing. If you do not regear with Huge overweight tires you will destroy your transmission. Had he regeared he would have not had to put a tuner, intake and exhaust on the truck. Engine size does not matter as a V6 4.2 will always be gutless, but regearing will keep it the same amount of gutless with big tires

 

Lol very true

 

I have always liked getting the biggest engine offered in a vehicle. That way, it is ready for anything. I would get the 6.2, and the lowest gears I could possibly order. Then when you put those big tires on there, you wonder what happened to the engine that was in there.

 

I did look it up and I think I know my answer. Ford does offer the 6.2L with the 4.10s and with the biggest towing package I think I will be safe for a while!! It comes with a bigger transmission cooler, oil cooler, and a couple other add on's. I'm going with a BDS 6" suspension lift, 37"x13.5"xR18-5 1/2 BS with the Black Fuel wheels and Toyo open country M/Ts. Also I'm putting bushwackers fender flares on. In British Columbia we have to keep the tires in the fenders. Hope I don't have to get mudflaps!

 

I like to work on this same theory!

 

In stock form will the 6.2 get better or worst gas mileage vs 5.4 triton

 

I tow with my truck all the time, probably 10k a year dragging a 7500lb enclosed race trailer. Tons of people run trucks with tall tires and tow all the time with tall gears. The transmission has no idea if its pulling larger tires or hooked to a heavy trailer. All it knows is that it sees load and adjust gears based on input speed and load.

Now the truck will perform better with lower gears to compensate for taller tires. But it will not damage it...

 

Actually no, it is increasing rotating mass which strains hub bearings, u joints and the transmission. The increased force needed to turn larger heavier rims and tires causes you (the driver) to put your foot farther into the floor to try to keep up with traffic. Thus the transmission lives its life (and engine for that) at 3-4000 RPM instead of ~ 2k on dead stop take offs. If you have to half throttle every take off to get going it wears stuff out quick.

You can go ahead and say the transmission has no idea if you have big tires or a trailer, but the internals say otherwise. Gears reduce the amount of effort it takes the engine and transmission to get that mass moving, thus less strain on the metal bits between your right foot and the huge tires.

You can keep your 3.55s and put on some street queen 38" tires. I've replaced a number of transmissions and hub bearings because they cannot handle the rotating mass.

[Edit] Also, rotate stock tires and rotate aftermarket tires that weigh close to 150-200+ pounds. Tell me that it would be easier for the truck to rotate an extra 800lbs of rolling mass then then the stock wheels and tires in which it was designed and geared to do.

 

^ Dead, spot-on!

It's easy to say machinery doesn't "know" it's turning more weight, rolling mass, etc. All that proves is that machinery isn't intelligent. As far as that goes, the engine doesn't "know" if it's being run at WOT all the time. But give that a shot and let me know how long the internals last.

Physics is physics.

 

Actually NO... you missed my point. All the transmission is seeing is resistance, whether its from tall tires or tons of weight. When you put the extra load of a trailer behind you its doing the same thing essentially. Probably worse. Obviously running small tires and not towing anything is better than the opposite.

But your statement that you will fry your transmission unless you re-gear is bogus dude.

 

The transmission only transmits tq... thats it.. Whether you use that tq to spin heavy tall tires or pull a heavy transmission, it doesn't care.

It is designed to be loaded and tow. So it can stand taller tires with out fear of burning up.

I'm sorry that this escapes both of your understanding of reality and physics. But it is what it is. Tall tires/heavy towing loads produce the same force on the transmission.

Now towing heavy loads with Tall tires will obviously be harder and generate more heat than either case by them selves.

 

So you say that larger tires = like towing on the transmission

You are also saying that if you tow 5-7000lbs daily your transmission will last and will not wear anymore then as if you didn't tow daily? You realize on the tow packages from Ford they automatically up the gears to a 4.10 over the 3.xx gears to help take stress on the engine and transmission? You are saying that the added stress does not affect longevity at all?

The more resistance the harder it is for the transmission to rotate internally. This stresses the internals and raises temperatures. Same goes for rear ends.

Taller tires also changes the gear ratios, this also hurts towing too. If you decrease tire size it creates a better gear ratio for 0-60 and thus the truck works less hard to move the mass. Larger tires take your 3.55 and depending on size make the rear differential gears anywhere from more like a 3.00 to 2.00:1 ratio. Show me a truck that anyone sells that has a 2.xx rear end from the factory. The eco boost come with 3.31 gears for fuel economy and ford rates them to tow LESS then they do with 4.10 gears. I wonder why?

 

When I baby it, I get better than I did with my 2006 5.4L. I get right at 16.6 mpg on my commute now when I take it easy. I barely saw 15 mpg with my 5.4 running the same route the same way.

When I pound my 6.2L on the drive home, I get around 10.6 mpg .. when I pounded my 5.4L, I got about 12 mpg.

 

Almost equal mpg is good considering its 100 more hp and larger motor.