Explorer Overdriver Question

Hi All,

I have a 1998 Explorer Sport with the high output 4.0 motor, 5 speed auto and 4.10 gears. I had a heavy duty trans cooler installed and all runs well.....she pulls like a mule.

My question is about overdrive. I have read that its best to keep it out of overdrive when towing. I am towing about 2600 lbs + a few people in the truck. When I am on the highway with OD off at about 60 MPH she is turning about 3200 rpms, when I click the overdrive on that drops the rpms to about 2300.

My first tow, I kept the OD off the whole time (100 miles roundtrip)...she was eating gas like nobodys business....since then, I click the OD on/off depending on the incline, on flats and down hill, OD is on, then when I see a grade coming up, click it off.

Am I using this feature right?

Thanks,

MS

Re: Explorer Overdriver Question

That is about how I used the OD on my Mercedes MLs, MS, but that is only because I asked Mercedes how to do it. You need to ask Ford, not us.

Re: Explorer Overdriver Question

I do mine by feel. If it feels like it is starting to lug I drop the OD. Depending on the downgrade I will turn it off so I use more engine braking and less normal brakes. Puts you in better control that is why big rig drivers that I have known will drop a gear or more before starting downhill. They won't have to ride the brakes. With my 99 Ram 1500 quad cab 2wd 5.2 Magnum 3.55 rear end even unloaded it doesn't like going up moderate hills at under about 1800 - 2000 rpm and it really objects to 1500rpm, but put it up at about 2500 and it will not only deal with it I can accelerate up it. Anything higher in the rpm ranges and it will scream up it. It is because at the lower speeds it is way out of it's powerband. I pull about 1600-1700 rpm on the highway about 65mph and will lug a little going uphill. Drove behind a Corvette doing closer to 90mph (sorry no idea as to rpm, I was watching the road) and the old beast pulled like a freight train. I floored it to see what would happen and she just knuckled down and went faster (AWESOME!! been working about 2 years learning how to get the old beast to do that). Love my truck, but Mopar really screwed up picking the gearing setup and tuning on these trucks. I am working on it slowly to fix it as I learn how. Learn the power band of your rig and you will learn when to shift and when not to. Besides 2600 pounds on that truck should only be 1/2 to 2/3's its tow rating. Use some common sense, learn your rigs power band (likes and dislikes) and you will be fine. Good luck and let us know what you find as you play with it. I strongly recommend taking it out under different circumstances and seeing what happens. Take notes and the truck will tell you, what it likes.

Re: Explorer Overdriver Question

BTW, did I mention that I have gotten this old beast up to about 15mpg intown reasonably flat and closer to 19mpg on the highway. When I really started working on it I was getting 10mpg, uphill, downhill, highway or city it didn't matter.

Re: Explorer Overdriver Question

I think you have the right idea, one thing you might want to add is transmission temp gauge though if you do tow with OD on. I also used to tow with a Explorer Sport with 4.0 SOHC motor and although my boat weighs more I never towed with OD on. Just as FYI, the 5R55 transmission in your truck is not known for durability, so it can use all the help it can get. I vote take the mileage hit and leave it off.

Re: Explorer Overdriver Question

I tow with a 2001 Sport Trac, my rig is just a little heavier than yours but not much. I tend to use the OD the same way you do, on flat open highway I leave it on,you can usually feel the torque converter lock at steady speed (a slight drop in RPM) from what I understand if the converter is locked you are not getting a lot of slip and the transmission is not getting beat up too badly. However as soon as I need some accelaration or the road gets hilly the OD goes off. I almost never drive on a secondary road with the OD on.

Re: Explorer Overdriver Question

With your weight, you're fine. Personally, I would leave the OD off and drive a little slower. You would save a little gas and still stay in the bottom of your torque curve. IMO, 2300 is too low for that motor except when going downhill. You can lug the motor on flat stretches without realizing it. $0.02

Re: Explorer Overdriver Question

When towing with our minivan, I turn the OD off. Yes it uses more gas, but that is a whole lot less expensive than having to have the transmission rebuilt and being without a car for a week or more. My van gets about 24mpg normally and 18 with my boat behind me. Calculating it out means that I'd have to do about 17,000 miles of towing at $4.20 gas price to save enough money in gas to risk my transmission. Not worth the risk in my book.

Re: Explorer Overdriver Question

Tow with it OFF. OD is pretty weak in the explorer tranny and going in and out of overdrive wears it out ALOT quicker. It don't matter if the computer does it by hunting gears or you doing it by playing with the OD button while towing.

Re: Explorer Overdriver Question

The temp guage is a great idea, I am wanting one for my truck. The other two things that would probably help are a shift kit (if available) and a oil cooler for the transmission. Dodges are known to have low fluid pressure to the clutch packs so they slip fairly easily and overheat horribly. The PO overheated the 4th gear clutch pack so bad that the friction pads (I think that is what the "soft part" is called) were completely black, the steel bands were bright blue (very seriously overheated), the 3rd gear clutch pack was starting to look like 4ths and there was a whole lot of sludge in the pan near the magnet. I would guess easily triple (probably more than that) the amount at about 80k miles that I had when I changed it at about 30k miles. The shift kit I had installed when I had to have the transmission rebuilt fixes that and it shifts quicker. These things help to reduce the heat of the transmission by reducing slippage. Of course the oil cooler acts like the radiator just a simple air to liquid heat exchanger, however everything that you do to reduce the oil temp of the transmission to a point seriously increases it's life. I drove it almost 30k miles before I changed the fluid after the rebuild and there was only a little sludge near the magnet and the filter looked almost brand new. The last time I changed the fluid closer to the recommended 15K miles and there was so little sludge it wiped clean. To help prevent messes when I change the fluid I bought a drain plug kit (about $5 at your nearest parts store) and installed it. Very easy install and makes changes a lot easier and cleaner. Most if not all of this information may be true for your Ford as well. The manufactures sacrifice durability for comfort when they build a transmission. As a general rule the more it slips between gears the smoother the ride, problem is it wears out the clutch packs a whole lot faster. Of course this is good for them and others as you have to rebuild it faster than if the did it right the first time. Oh well, not much you can to but keep the vehicle you like and make it the way you want it with lots of research and planning. That is exactly what I am doing to my truck, reengineering lots of it as the OEM parts wear out. Good luck and let us know if we can help anymore.

Re: Explorer Overdriver Question

Sacrifice the MPG, stay out of O/D with the Explorer and your tranny will live to tell the tale. Our Jimmy does 17mpg no matter what gear it's in or what load it has or has not got on the back.
Just my humble opinion.

Re: Explorer Overdriver Question

I have a 2004 Explorer and it kicks off on its own when I toe my boat so I would say leave it off.