I would like to disconnect the front drive in my AWD Avator to improve gas millage.

Has anyone ever done this and will it effect the truck in other ways ?

 

I think unplugging the AWD could become problematic. Explorers had a bad batch of 4X4 control modules on 4wd explorers several years ago. My moms 03' and another family members 02' both had the modules go out. So they could drive it to test they unplugged the 4X4 module and drove around a couple days to see if the problem went away. They didn't say of any ill effects from unplugging the module, but I wouldn't do it on an AWD becuase its automatic and not switch operated like the 4X4 models. I hate AWD and FWD. AWD is a waste of gas IMO and I prefer hubs and a manual or ESOF transfer case like on the pre 02' explorers.

 

Your front wheels are connected to the differential permanently. You would need to remove the axles and plug the differential where the axles would have been. Once you have all that done there still won't be much of an improvement in mileage.

 

i would just leave it. i hated my 03 exporer always kickin in when my tire slipped.

i love my superduty and its hubs and esof

 

You would also need to disconnect the transfer case completely and install a new rear driveshaft from a 2WD model. The design is similar tot he AWD system used in the Aerostar. The function of the system is actually amazing. It works very well on pavement and is well suited to applications where consistent traction is desired. On road, it works much better than the 4WD systems I have used. If you leave a $WD vehicle locked up, you loose the ability to tun, and it is very good for keeping a vehicle moving straight and at preventing fishtailing. But when a turn is desired, 4WD impairs the ability to steer, largely because the front and rear axles are locked in a 1:1 ratio.

The AWD on the Aero, and the similar system on the AWD Explorers, run an open torque split most of the time, ~30% tot he front drive shaft, and ~70% to the rear. The transfer case acts as a complex hybrid differential and planetary gear, allowing it to split the torque unevenly. It then has multiple speed sensors. These sensors tell the module to engage a lockup device, which locks the differential in a ~50% torque split. It then releases the lockup after a few seconds. This arrests any fishtailing effect without compromising the ability to steer.

the most common failure point is one or both of the speed sensors begins putting out an erratic signal which fools the module into believing the vehicle is slipping. Sot he most common problem is that the lockup can occur on dry pavement when making turns, often detected as a clunking or binding. But otherwise, the modules are very reliable. The whole system is much safer than 4WD on paved surfaces, because it only engages when needed, and the full time torque split makes the vehicle stable. On the Aerostar, and presumably the Explorer, the system only engages lockup at speeds below 35 mph. This prevents the potentially dangerous effects of 4WD lockup at higher speeds, which can cause the tires to bind, resulting it suspension preload that can roll the vehicle. When it is working correctly, it has the added benefit that it is always engaged, so the driver does not have to manually engage or disengage the system.

I have found that the implementation on the Aerostar allows me to easily handle conditions that other vehicles cannot handle. I have driven through deep piled snow that even larger 4WD trucks were skidding around in. I once tried to teach a younger sibling how to drive in snow, and made the mistake of using my AWD Aero. It was a disappointment to me, because the vehicle did exactly what it was told to almost as though there was no snow at all. The constantly engaged system also improves the braking marginally, since the physical connection to all four tires does reduce the likelihood of locking a tire to some degree. You could take the vehicle up to around 40 mph and then do a turn before it would start to skid, but even then, it felt very controlled. The brakes would cause it to understeer somewhat, and were far more effective at allowing the vehicle to skid.

I ended up taking them on the same route with a 2WD vehicle which then showed how treacherous the snow really was. I have had my AWD Aero for two years now, and have grown to love the AWD despite the fact that it does penalize the economy slightly. I live where there is enough snow to justify it.

BTW, I recommend to everyone to familiarize yourself with the vehicles handling in adverse weather by finding a large empty parking lot and driving around to see what the vehicles limits are. It helps you become a better driver and better learn the vehicles limitations. Don't ever try this on the road, but if an emergency happens, it is nice to know what the vehicle can handle.

 

how about removing the driveshaft?

 

I agree. I hate the auto 4X4 also. Tends to engage with a thud somtimes and no doubt shocks the drivetrain.

I love the setup on my SD, manual hubs and manual transfer case, most reliable your going to get. You have to get off your **** to lock the hubs but no hub vaccum issues like with ESOF.

 

Don't bother. Remember the front wheels are always engaged with the front differential so the front end is always turning. I am not sure of any potential damage to the AWD system/transfer case by doing that but it won't make a difference in mileage.

 

The transfer case for AWD works like a differential. If you remove the front driveshaft, all the torque will shift tot eh missing driveshaft and vehicle won't move. The module will interpret it as slipping and engage the clutch. However, the clutch is not meant to handle that kind of load, and it will quickly burn out.

Seriously, the AWD does not penalize you much. If you really want to improve its fuel economy, replace the lubes in the front rear and transfer case with full synthetic fluids. Personally I recommend Royal Purple, but Mobil1, Redline, and Amsoil are top notch choices too.

 

I can easily see a 2wd explorer getting 2+mpg more than an AWD model on some situations. When I have the hubs locked on my SD mpg goes down and that just turns the front driveshaft and axle and I actually have torque, which the explorers don't have.

I agree there will be very negative effects to disabling the AWD system.

 

You are forgetting that all explorers from 95+ whether AWD or 4x4 do not have hubs. The axle is connected to the hub with no disconnects. The increase in mileage from a 2wd to a 4wd vehicle is not only due to less rotating mass but less mass period. The 4x2 trucks don't have the front differential, driveshaft, axles, transfer case, etc. They are lighter than the 4x4 counterparts.

 

I'm aware of the weight difference netween 2wd and 4wd. I'd be willing to bet the drag from the rotating mass has more effect on mpgs than the extra 300-400lbs.

If you don't need or never use 4X4 or AWD it would make much more sense to purchase a 2wd vehicle in the first place and save the $$$.

 

My wife has had two and four wheel drive models, same motor in each.

Fuel mileage difference between the two was basically nil.

While her 4 wheel model does have the ability to turn it off, she leaves it on "Auto" all winter. Control trac system, the best one they ever made in my book.

 

The only extra drag you would have is the air resistance and two seals and bearings that seal said shaft. In comparison to the power of the engine, this is almost nothing. It is certainly a lot less resistance than the the extra friction in the tire from the added weight. Also the extra weight bites into economy every time you go up and incline, but doesn't really return the favor and save fuel going back down.

I would agree however, that if you do not need/use the AWD or 4WD option, then you shouldn't buy it.

 

How do you figure. If there are no hubs to disengage the wheel from the front drivetrain, all axles, gears and etc will spin all the way back to the transfer case.