first, thanks for replies and comments. I am not a mechanic, truck guru or towing guy. Let me get to the good stuff.

2015 F150 XLT FX4 4" lift, small programmer tune, 35x12.5x20, Roadmaster HD active suspension. I bought the truck with the tires, in assuming no gearing changes were made. Towing a 8K TT. The Ford Gear sheet says it came with 3.31, which I know is terrible for towing. I feel the truck is struggling up inclines, constantly down shifting in tow haul mode. I am wondering how much better it would be to change the gears? Is it worth it? Etc. I added the OEM brake controller.

Any advice or recommendations for making towing easier and less stressful on my truck?

 

Return to stock height and tire size. Even then it will be a lot of trailer for a 1/2 ton truck. I'm towing a 6500lb travel trailer with 3.55 and a 10 speed and guess what? It downshifts going uphill.

 

I wish I could return to stock tire size, but just paid $1600 for the four brand new Toyo ATIII. Returning to stock height can't happen unless I return to stock tire size.

I think a Rouch cold air intake and a towing friendly program would be cheaper and easier then returning to stock tours and height. I also read that programming the transmission to shift 1K rpms higher then the factory settings is a huge help.

Thanks for the comments.

 

A program might help, but 1000rpm is going to spool those turbos (if you have an EcoBoost) a lot more often, generating a lot more heat and wear. CAI will give you a little better throttle response, but if you don't open up the exhaust you won't see much improvement. By the time you spend the $1500 on those two items, you could sell the tires and wheels, drop down to a 32 and stock ride height, and you'll be spending the same or a little less. Regearing is also very expensive, especially if you have a locker in the rear. Smaller tires essential does the regear for you. Also, you'll see increased performance by having significantly less rotational weight with lighter tires.

 

Cold air intake comes from factory...

What does payload sticker on door jamb say?

 

If it is lifted with a traditional 4" kit, chances are truck can't be lowered as the frame members have been cut to fit the brackets required for the kit.

To do gears, you will need to go pretty low. The 3.31 is a high gear for towing. 3.31 is a vry high gear for 35" tires. Double negative.
You would need to regear just to make it perform as stock. Additional low gear will offset the additional power loses of the tires to assist with the trailer towing.

Unfortunately you'll need front and rear axles to do the job.
I assume you have the Coyote. That motor does like to rev to make the power. If you are trying to RPM low, or short shifting, you may need to let the motor humm a bit to do it's job.

To consider the gear route -how low can you go and not have it not be cost effective as your daily driver. I'd suggest going straight to the low gears to get your moneys work, and to make driving more fun. The drawback though is highway mpg. You'll be happy to have lower gears with 35's if you pretty much drive around town.
It's all a compromise to a certain degree.

I've never had a tuned vehicle to know just how much better power can be made. One of the favorites seems to be 5-star though. Look into their tunes to see what they can offer. I don't know what else is out there (drawing a blank on the others). Maybe Livernois Tuning is a name?

 

I figure the truck is pulling near max payload, if not over. Being an extended cab I scratched my head wondering if there is more payload available to him.
I was going to ask that question, but it won't change the fact it's still sluggish. haha

 

I was told payload is 1654, tongue weight TT is 760, i weigh 260 and two 90 lbs dogs. I will double check door sticker. Thanks

 

I have the 5.0

 

On an 8,000 pound trailer, your tongue weight would be 800 - 1,200 pounds, ideally 1,040 (13%). Sounds like a brochure payload. 760 is 9.5%.

Hit the scales fully loaded with full gas. 3 weights, with wdh attached and bars tight, with bars undone, and truck by itself.

I suspect you are well over payload.