How Determine Rear Axle Ratio? (1999)

Hi all - First Day, Second post: How do I determine the rear axle ratio on my new-to-me 1999 EB 4x2 4 door 4.0 SOHC Explorer? I actually have the original sticker, and it doesn't mention anything about it. Also doesn't mention "Towing Package" or "Towing Option" which worries me a little. The step bumper has a placard that states it can carry a 3500# (350# tongue weight) trailer, but this model Explorer is supposed to be able to pull either a 4500#trailer (if it has a 3.55 rear end) or a 5900# trailer (with the 3.73 or 4.10 rear end), according to the owner's manual. I assume that I'll need to get a weight-distributing hitch to pull more than 3500#, regardless of which rear end it's got? Suggestions? Also, How do I find the hookup for the trailer lights? If it doesn't have any special towing package, will it even HAVE a connector for the trailer lights? If it doesn't have the towing package, any suggestions on an auxiliary transmission cooler?

Thanks,

Kip

 

[chrisis]

the easiest way to check the gear of each explorer is looking at the side of drivers door and you should see an axle code from one below.

41 - 3.27 non-limited slip (Explorer/Mountaineer)
45 - 3.55 non-limited slip (Explorer/Mountaineer)
46 - 3.73 non-limited slip (Explorer/Mountaineer)
42 - 4.10 non-limited slip (Explorer/Mountaineer)
D1 - 3.27 limited slip (Explorer/Mountaineer)
D4 - 3.73 limited slip (Explorer/Mountaineer)
D2 - 4.10 limited slip (Explorer/Mountaineer

hope i help

 

[cgriffin_5139]

or there is a tag on the axle itself

 

[cgriffin_5139]

kip there sould be a conector on the driver side under the break light for the lifgts. you have to get under the x to see it.

 

[gijoecam]

Ditto on the axle codes: Look at the door sticker or the axle tag for the info.

For the lights, there is a plug up behind the driver's side taillights. All you would need to do is buy the adapter ($15 from the dealer IIRC) and use that to feed the trailer light wiring on the connector. However, with a trailer that large, you absolutely will need trailer brakes, and for that, you'll need to wire the truck for a controller.

Good luck!

 

[KipHouston]

Hi guys - thanks to all for the help. The door sticker says I've got axle 42 - 4.10 non-limited slip. So, according to the manual, I should be able to pull a 5900# trailer. And thanks for the recommendation to get trailer brakes for a heavy trailer, joe. That's an excellent idea I might not have thought of.

I found a couple of connectors under the rear bumper, one on the driver side, one on the passenger side. The driver's side one is sorta flat - maybe an inch long by an eighth thick. The passenger side one is circular, with three small rectangular tabs, and it's female. Any idea what that thing is?

So now I just need to: 1)Find options on load-distributing hitches, 2) Find out status and options on auxiliary oil and tranny coolers (if I ain't already got 'em), 3) Learn about trailer brake controllers and how to wire the truck for one, and 4)Buy a trailer! Anyone who'd like to offer assistance with any specifics on #1, 2, or 3 above, please feel free!
Thanks again,
Kip

 

[gijoecam]

With regards to your capacity, yes, with the 4.10, you're rated for 5900 lbs. However, you're limited to a GCWR of 10,000 lbs. My 2-door weighed 4300 lbs, so your four-door is probably around 4800-5000. Now, add in you (200), your spouse (150) (I'm just making up numbers... please don't hold me to this), your 90 lb dog, a child, child seat, diaper bag, snacks, etc (40), a full cooler (50), and a couple of suitcases (100) and you've just chipped 630 lbs off your towing capacity, reducing it to 5270.

Now, look at a nice pop-up trailer for example... start with a nice-sized 3000 lb pop-up. Add 30 gallons of fresh water (210 lbs) propane tanks (20lbs of propane in each one, plus the weight of the tank itself for a total of roughly 70), fill the fridge with 20 lbs of food, an auxiliary battery (50), the kids' bikes (60), kitchen supplies (100), assorted camping gear, like carpets, chairs, etc (100) some firewood (300) and your 3000 lb trailer just ballooned to 3910 lbs. And that's being pretty conservative I think....

Just something to think about, that's all. You can be right up near your limit before you even realize it! Good luck!

-Joe

 

[cgriffin_5139]

Well if Evan and his mounty can tow this, you should be fine.

 

[terminator0723]

Ah Darn Why did I read this? I was hoping a had a 3.73 but apperantly I have a 45 which is the 3.55... which means I can only pull 4500lbs and I was gonna pull 5000lbs.. Guess it's time to find a trailer 500lbs lighter

 

[gijoecam]

Trust me... 4500 lbs with a V-6 Explorer is pushin' it even with a weight distributing setup. The SOHC motor likes to rev, and even with the 4.10s in mine, it used to work pretty hard to pull my boat the three miles to and from the launch ramp. When the brakes went out on the trailer, it was all I could do to not skid through the intersection.

-Joe

 

[MountaineerGreen]

Well if Evan and his mounty can tow this, you should be fine.

It should be noted, I went through some significant modifications to tow that camper safely and competently. To begin with, I started with a 5.0 AWD drivetrain which is more capable than the v6 drivetrain. Then, I got the heaviest rated hitch I could find, a weight distribution ball mount set up, an electric brake controller, transmission temperature gauge, upgraded leaf springs, load range D tires, a selectable transfercase, and now 4.10 gears. I don't believe any explorer in stock form could safely tow that load.

 

[KipHouston]

On the other hand, terminator, maybe you saved yourself a $1500 transmission!

As long as we're on the subject, can anyone characterize how easy or difficult or expensive or reasonable or ridiculous it would be to consider trying to change one's axle ratio? Not that I am personally considering doing it, but I've been curious about what's involved. I am NOT a mechanic, in case it's not obvious.

Evan - Holy Cow! What much did THAT set-up weigh???

I really appreciate everyone who has chimed in - I don't know much about towing, but I want to do it right snd safely, with as many options on travel trailers as possible/reasonable and not tear anything up on my new ride, which I love already. Another way to put it is that I'm trying to find out what my option$ are (read: what's the heaviest I can safely tow?) and what do I need to do/spend to be safe?

Finally, I was wrong about the flat connector I described, that was something else, but I did find what appear to be TWO identical connectors - one on the driver side, with a cap or cover on it, and one on the passenger side, that appeared to be identical, except it didn't have a cap. Does that make sense or surprise anyone who knows about these things? I have photos I can post if it would help. The connectors are circular with 2 rows of 4 connectors in the center, and 3 little tabs around the outside of the circle.

Thanks again for all the info,
Kip

 

[dman726749]

the light plug you are looking for is on the passenger side....its the round one you described above.

 

[MountaineerGreen]

As long as we're on the subject, can anyone characterize how easy or difficult or expensive or reasonable or ridiculous it would be to consider trying to change one's axle ratio? Not that I am personally considering doing it, but I've been curious about what's involved. I am NOT a mechanic, in case it's not obvious.

Evan - Holy Cow! What much did THAT set-up weigh???

I just did a gear swap, did mostly my own work to save money. My swap with an aussie locker ($250) cost ~$800. I won't hijack your thread with the details, but I'll post a link to my thread, then go on it and break it all down.

http://www.explorerforum.com/forums/showthread.php?t=178966

Truck, camper and all was just under 10k. Camper weighs 4400 empty and dry. I got a DOT officer to weigh me using his scales, I need to find my notebook with my axle weights and I'll post exactly what it was.

 

[KipHouston]

Which lights connector to use?

Hey there Evan, and everybody else -

Thanks for the link to the gear swap - that Aussie locker sounds interesting. Have to add that to my wish list.

I found two identical lights connectors, one under/behind the bumper on the passenger side, and one on the driver's side. The driver's side one had a cover on it. I guess it doesn't matter which one I use, or else I'll find out if they both work once I get a trailer to hook up to it. I got one person telling me to use one the passenger side, and another telling me to use the driver's side! Oh well, like I said, can't be too hard to figure out. Photos of the connectors can be seen at

http://www.box.net/public/gljfe7jhky

Also, Evan, I noted your trailer hitch thread at

http://www.explorerforum.com/forums/showthread.php?t=176203

and the photo of your hitch - How did you get the lights connector set up thru the bumper like that?

Thanks again,

-- Kip

 

[gijoecam]

I've never seen the one on the passenger side before, although, admittedly, I've never looked there either.

The one on the driver's side is where the OEM harness is supposed to connect. If you buy the kit from the dealership, it'll come with the connector, the bracket, and the bolt to mount it to the bumper. Otherwise you'll have to find a way to secure it up out of the way when not in use. When last I saw, the harness alone was like $15 or so, and the kit was around $17.

-Joe

 

[MountaineerGreen]

Hey there Evan, and everybody else -

Thanks for the link to the gear swap - that Aussie locker sounds interesting. Have to add that to my wish list.

I found two identical lights connectors, one under/behind the bumper on the passenger side, and one on the driver's side. The driver's side one had a cover on it. I guess it doesn't matter which one I use, or else I'll find out if they both work once I get a trailer to hook up to it. I got one person telling me to use one the passenger side, and another telling me to use the driver's side! Oh well, like I said, can't be too hard to figure out. Photos of the connectors can be seen at

http://www.box.net/public/gljfe7jhky

Also, Evan, I noted your trailer hitch thread at

http://www.explorerforum.com/forums/showthread.php?t=176203

and the photo of your hitch - How did you get the lights connector set up thru the bumper like that?

Thanks again,

-- Kip

You've been searching-

If you don't have the factory towing package, you may need a harness from www.etrailer.com. It may use both connectors to get signal from each side

As for the plug, It was cut with a small wheel on a die grinder a little at a time, then filed to fit the plug just right. I used the bracket that came with the plug to trace a hole to cut. I removed the bumper to do that, made it much easier. A properly sized, high quality hole saw could achieve the same effects, I just didn't have one.

The aussie locker has its benefits and drawbacks, it works well, but when turning sharply under power, I spin the inside tire often. I can only assume this will accelerate tire wear. I have been trying to adapt my driving so that I don't have to make sharp turns under power. The locker will release when turning while coasting, but if there is pressure from the driveshaft, it locks.