You can spend a lot of money on things that will help a little bit at best, or you can spend $1,000 on gears and make a BIG difference. Do the gear first, and don't mess around at 4.10. Go at least 4.3 and if the primary purpose of this truck is towing, I would go 4.56.

Best bang for the buck and it isn't even close. Even more so because you only have one diff.

If you do this, we would really appreciate an afterward report.

Bill

 

I've contemplated buying a short wheel base F250 with the 5.4L and all the factory towing goodies, but for now I need to see what I can get out of what I got. I just don't know if $602 is worth a Banks muffler and tailpipe kit.

 

You'd probably come out ahead if you just had the local muffler shop fabricate you duals from the manifold back.

 

I'm definitely sold on the 4:10 gear. I don't want anything higher since I will maintain 3rd gear as my primary towing and don't want to kill my top MPH with the truck. I'm aware off internal modded 5.4L but was curious what other F250 5.4L owners do for towing. Flowmaster makes a nice cat back for $215 but it is single 3" as apposed to Banks 3.5". I wonder if there would be a difference in the diameter. I did notice on our last trip the passenger side floor board emitted and immense heat in the cab as compared to the drivers side being cool telling me the exhaust is not flowing well enough and is getting too hot.

 

Talk to your gear vendor. It will cost you just as much to go 4.1, and I think you will be disappointed and wish you had gone lower. I expect a good gear vendor will tell you the same thing. You can still use any gear you want, and that motor will have plenty of top end to give you all the speed you need.

All those other motor mods are going to get you, what? 25 HP?

Maybe you just enjoy engine mods and want to do them. Nothing wrong with that, have a ball. After all, you can see them, hear them, show them to your friends. Gears are kind of boring.

Bill

 

I don't think you'll notice a difference between 3 or 3.5 inch. Remember to replace the Y pipe if you go this route and consider replacing the cats with a performance replacement.

 

I will definitely talk to my local dealer about what the best gear would be for my application. As for motor mods I don't do them just to do them, though I do have a ball wrenching on anything. I see concerns as in excessive heat produced by the exhaust telling me there is a restriction and could see a gain with a better flowing cat back. If I was to put in a lower gear and rev the motor alot higher than I am now then I can see a benefit in an electric fan taking that load off the motor the clutch fan produces. Actual horsepower gains don't really mean anything as long as these "minimal" gains help the truck pull a hill better and keep it from down shifting as much. And I find gears essential, not boring.

 

I have yet to find a replacement Y-pipe for this truck though I've heard of the later year 5.4's have a better design from the factory.

 

Use a generic Y-pipe. The latter years are much better flowing, but no closer to what you need and a lot more expensive.

 

From Ebay:
http://cgi.ebay.com/ebaymotors/00-05-Ford-Excursion-6-8L-V10-High-Performance-Y-Pipe_W0QQitemZ220153641139QQihZ012QQcategoryZ33633 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Or Polished:
http://cgi.ebay.com/ebaymotors/Stainless-00-04-Ford-F250-F350-6-8L-V10-Exhaust-Y-Pipe_W0QQitemZ220153640974QQihZ012QQcategoryZ33630 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Don't know about the quality or results but you can't beat it as far as the price.

 

I like that y-pipe. Very simple. I've been reading this article and trying to apply its theories to my truck. http://www.performanceunlimited.com/...g/results.html

 

Uh, towing anything 70 - 80mph causes too many RPM's. You gotta slow down and enjoy the ride.

Well, okay. I have the 5.4, and have the Superchips, but it didn't really help much. It made the shifting of the tranny waaay smoother, but didn't really help much beyond that. I otherwise have no other mods. I do have a 4.30 rear end in my garage, waiting on me to get off my duff and get it put in. I believe, as many others here have stated, that that will give you the most bang for your buck.

 

I have a 07 F250 CC SB FX4 with 5.4L auto 3.73,
I use a Superchips programmer 1815,
I have a K&N FIPK intake
Airraid throttle body spacer
No cat, Aeroturbine 3030XL muffler with its Stealth 200 exhaust.
stock tires and all that.
I tow a 6k lbs camper many times thru out the year.
I live in the mountains of montana
towing at hwy speeds 65-75 mph i can do in 4 gear around 3k rpm sometimes on a hill it drops to 3rd gear and 4k rpm to maintain speed. on flat ground it will go up to 5th about 2k rpm but will bog and need to downshift at the slightest incline.

 

Longbed,

First thing is that you should NOT be towing a trailer 70-80 MPH, that is dangerous and not necessary. It threatns your own safety and also the safety of others around you. I tow my 22FT TT around 60 on the highway and I generally do not go over that. Some trailer tires are not speed rated for over 65MPH so watch out for that as well.

I own a recently purchased 99 F250 Super Duty, 5.4 A/T, 4.10 LS.

I was told years ago that you don't want to tow in overdrive unless your owner's manual says that you can. My owner's manual makes no mention of towing out of overdrive, so I assume that I can, HOWEVER you MUST be careful.

I (as you) find that on small grades on the highway, my RPM's drop too quickly and I have to depress the accelerator to get it to downshift out of OD too often (NOT GOOD).

I find the best towing performance is that if I lock OD out and just run in 3rd gear.

With my 4.10's, at 60 MPH I am turning 2800 RPM, approximately. At first I did not like turning these RPM's constantly, but this IS a Small Block engine and that is what it's designed to do. At 2800 RPM it doesn't even feel like it's working very hard.

With OD locked out, I maintin 3rd gear on any highway grade and I only drop to 2nd on steep mountain passes.

If you want to tow in 3rd with OD locked out, I would strongly reccomend AGAINST any gear lower than 4.10.

I plan on gutting my CAT in the near future to see what gains that produces. I GUARANTEE our stock exhaust has our 5.4's "by the throat" so to speak. The CAT on my truck is HUGE and RESTRICTIVE. I only put about 1500 miles on my rig per year so I am gutting my CAT, if you run yous more, I would opt for a nice, free-flowing CAT.

I don't think there is any performance gain by going to a 3.5" exhaust. When I replace my current stock 3" cat-back exhaust, I will probably buy the Flowmaster Force II or American Thunder system (if the AT is available for my truck. I don't see much restriction in my stock Y pipe, so I will probably leave that be for now.

I don't put much faith in the "chips" or "programmers" as Redford accurately stated. For your case, I'd go with a set of 4.10's or possibly 4.30 gears, a high-flow muffler and a good cat-back and just be happy with it.

I will say with the 4.10's and LS my 5.4 feels pretty stout, even stock. A LOT more so than the 89 Chev K1500/5.7 I traded in for it. I have been a FORD man for a number of years, so I am glad to finally have a 99/newer SUPER DUTY, I always wanted one and always thought they were great trucks.

Good luck.

 

I'm going to try the Y-pipe linked above and a high flow cat first. Mileage and performance will be checked for improvements. Gears will be next and because I will never tow in overdrive I think I will be going with the 4:10. I'll go from there as I feel the need for more.