I am new to this board, seems like a GREAT place to get info & help!

First, I have a 99 expedition with 5.4, towing package, 17" factory tires & 3.73 gears. It has 77,000 on it, and just got a tune-up & radiator flush & had a trans oil & filter change at around 60k. My trailer loaded is approx 5000 lbs, and blocks more wind over the top of the exp. On flat ground or down-hill, it rolls at 73-76 mph in O.D. fairly OK. It likes to run 78-82 "power-wise", but I don't feel comfortable there. Problem is, any kind of wind or incline, and it's 3rd gear at 3100 rpm. It sounds like I am running it really hard there, so I back it down to 65-70 mph @ like 2700 rpm. Then, if the hill is bad, when it drops below 66 mph, it drops into 2nd gear at 4000+ rpm! If it had more low-end power, I could leave it in O.D. most of the trip & work it less & get better mileage. I want to run 72/74 mph without revving it to death.

I am familiar with upgrades, and think I am aware of all the ones available for the 5.4 exp. I am looking for more power for towing with simple bolt-ons. I think my best option is to put smaller 16" tires on it (instead of putting 4.1 gears in it) to get the rpm's up in OD. BUT, it seems the 99 exp 5.4 setups can't change the tire/gear info with the "chips" or programmers. So, I am looking at the simple things like:

K&N filter setup,
Programmer (chip),
and ?

Thought if it has to rev 2700+++, then electric fans would take a lot of work off the motor, along with underdrive pulleys. It feels like it makes more power just before it is totally warm, so I am thinking of adding a 180* thermostat too. I'm sure the cat-back systems would help as well, just didn't want to get too noisy or "drone" when cruising.

ANY ideas, thoughts, or input would be greatly appreciated!

 

Welcome new member!!! First of all i want to tell you that you SHOULD NOT pull that kind of weight in overdrive!! If you keep that up you will be looking for a new tranny. Overdrive is for cruiseing in a normal situation at highway speeds, not carrying or towing a heavy load. Your tranny will hunt back and forth causeing heat (very bad) for an automatic.
Now....the next thing you might try is going to a Magnaflow catback system and a WMS (ceramic coated) cold air intake. I have done both of these and it did make a differance. But please...get that Expy out of overdrive when you pull ( who told you to do that anyway?)

I would not change your thermostat either. This will mess up the emission reading and cause more problems.

In case you want to know................My trailer is a 1998 NASH 20' fully loaded travel trailer. My loaded weight with food, full tanks, firewood, beer, two dogs, extra water, tv set and whatever else my wife brings is around 5100LBS. I never see overdrive untill I unhook. My tach reads anywhere from 2500 to 3700 rpms when I pull the trailer.


good luck
mlaugh

 

It,s not hurting anything being in overdrive, i tow with mine in OD all the time on the flats and mild hills. If I encounter a Steep hil, or slow roads where it starts to shift alot, THEN I take it out. But as long as its not shifting, then your fine.

Ron
99 Expedition XLT

 

The actual shifting back & forth from OD to 3rd under a load is what will kill the trans. If it stays in OD for most of the time, and the driver takes it out of OD before the hill (before the load), there is not that much heat buildup at all.

As for the thermostat causing emissions issues, it can't make it much worse than full throttle most of the trip causing it to run real hot. I didn't plan on a big change there, just a little to help.

Anyone go to electric fans or underdrive pulleys ????

THANKS for the input!

 

Hi there,
I pull 5160 lbs of 8 wide in the mountains up to 11K ft. My trips usually last two to four weeks and range from 2500 to 7000 miles. I've made all the bolt on changes you can think of and reverted most of them back to stock because they simply didn't make a difference that is acceptable, usually because of fuel cost increase or much louder noise when at full throttle for long periods pulling up mountain passes.

If you want to spend the money, changing the effective rear end final drive ratio is really the most effective way to go whether through tire or gear changes.

The simplest, cheapest and most time effective thing you can do with the stock vehicle is to just let the engine develop it's power by getting used to the increased rpm. Keep the revs up and you can go all day long with out problems. And the slightly increased noise is not near the brain-splitting noise that headers or most flowthrough muffleres will cause under uphill, open throttle conditions for long periods.

Start stressing the overdrive and you will see the tranny heat up and the OD light start flashing, the shifting get erratic and violent.
I learned after a lot of experimentation over the years to just disengage OD when I hookup, period, then all my problems stopped.

Your Triton engine loves revs. You can literaly go for hours on end with it at 4200 rpm. I do it all the time and it shows absolutely no wear, heat or increased oil consumption on my 112K engine. I'd go higher rpm, but it always shifts down when it reaches that point on my '97. (Occasional high revs also creates enough heat to clean your spark plugs, valves, cat converters and mufflers of carbon buildup.)

summary: Save your money and use what you have. Forget about worrying about gas mileage, in the long run it not as as expensive as all the add on goodies plus labor.

Hope this helps.

 

I too, was thinking of a cat back system on here, if you read many of my posts I am TOTALLY disgusted with the towing of these vehicles, now mine is a 4.6 which is bad, but I gotta tell you 20 horsepower and 40 pounds of torque aint gonna make a HUGE difference, which , according to the manufactures is what would be gained by getting the exhaust, filter, etc.. I dont WANT that"real truck sound" I like my stuff quiet .. So I am going to do a gear swap in the future.. it seems like the most effective way to do what I want any way, I mean its got 3:55 in it.. which I feel is just pathetic for a vehicle so large, anything less than 3:73 is just not supposed to be in trucks like this.. at 75, im only taching about 2200 rpms, Oh well.. Just my 2 cents. The Electric fan idea is a good one, as my neighbor once did it on a 2.5 jeep Cherokee, and could REALLY tell the difference on it on the hills, I know this is alot smaller of a vehicle though.. But none the less, it works.
I also make sure when Im pulling the windows are down, and the AC is off unless im in town. Every little bit helps.

Ron
99 Expedition XLT

 

OK, just bought an 18 foot fiberglass boat. I'm not sure of the exact weight but it's got a 125 Merc on the back and a single axle trailer. I have an 00 Exp Sport with a 4.6. I put a 3" flowmaster cat-back system, K & N cold air induction and a 17XX superchip. Holy crap. I realize you have a 5.4 and probably have @ 270 horse power, but I can honestly say that the modification I made to my 4.6 were well worth the grand I put into it. I have more power, torque and it sounds great. While towing my boat, I often leave the trans in OD but if it seems as if the road is getting steep or I need to pass, I take the OD off and take off. I'm actually running 17" rims with 2657017s, a bit oversized and it still has power to spare. Best of luck....