Body on Frame vs Unibody

[13Sport]

FWD bias also means a few other limitations for towing.

1st - Torque steer tendency is increased in a towing situation. The bigger the load, the harder the acceleration, the more the tendency exists.

2nd - Weight distribution shifts the balance towards the tongue of the trailer. As a shift to the rear occurs, the front becomes lighter and traction becomes an issue. Think wet roads, boat ramps, etc. Tire spin and safety become a concern.

As far as the 2015 Expedition, I expect it will continue to be RWD. None of the articles I've read indicate otherwise. The Explorer shares a platform with the Taurus. The Expedition shares a platform with the F-150.

Correct me if I'm wrong, but doesn't TOW mode on the Explorer shift the bias to the rear? Or are we talking about the 2WD models only (in that case it's not FWD bias, it's just FWD right)?

 

[colintrax]

Correct me if I'm wrong, but doesn't TOW mode on the Explorer shift the bias to the rear? Or are we talking about the 2WD models only (in that case it's not FWD bias, it's just FWD right)?

That would only apply to AWD and even still it has a FWD bias.

 

[182RG]

Correct me if I'm wrong, but doesn't TOW mode on the Explorer shift the bias to the rear? Or are we talking about the 2WD models only (in that case it's not FWD bias, it's just FWD right)?

I think tow mode only changes the transmission shift points, and locks out OD. I don't know if it changes the behavior of the PTU. I've heard that some people with Explorers and AWD tow in 'Sand' mode.

Correct - I meant to say FWD for 2WD and FWD bias for AWD.

It's all about RWD. My Touareg TDI is 50/50 AWD/RWD bias (Torsen), unibody, and will tow 7,700 lbs and 770 lbs tongue weight. The engine is in-line.

 

[peterk9]

Correct me if I'm wrong, but doesn't TOW mode on the Explorer shift the bias to the rear? Or are we talking about the 2WD models only (in that case it's not FWD bias, it's just FWD right)?

The Owner's Guide just explains it as changing the transmission shifting and engine braking. It doesn't seem to say anything about shifting bias to the rear.

Peter

 

[Explorer0204]

Where have you been for the past 4 years? Lo

As we have previously discussed I am not much of a crossover guy and, after hearing that they aren't true 4wd the new explorers aren't suvs to me anymore. So if it ain't a 4th Gen or older it just doesn't really interest me like the older stuff.

 

[13Sport]

I think tow mode only changes the transmission shift points, and locks out OD. I don't know if it changes the behavior of the PTU. I've heard that some people with Explorers and AWD tow in 'Sand' mode.

Ugh I just went out and tested to verify, you're correct... Tow mod leaves the bias forward. Sand mode moves the bias middle (AWD), but even then it seems like a gross oversight on Ford's part. It certainly seems like the electronics are capable of moving the bias backward in Tow mode (which would make sense)

 

[colintrax]

Ugh I just went out and tested to verify, you're correct... Tow mod leaves the bias forward. Sand mode moves the bias middle (AWD), but even then it seems like a gross oversight on Ford's part. It certainly seems like the electronics are capable of moving the bias backward in Tow mode (which would make sense)

At 5,000lbs FWD is no big deal. It's the 10,000lb capacity fwd can't handle. My moms FWD escape has pulled my explorer out the mud and even flat towed my ranger. And FWD bias is more efficent. Meaning better gas mileage. Doesn't seem like an oversight to me

 

[Explorer0204]

At 5,000lbs FWD is no big deal. It's the 10,000lb capacity fwd can't handle. My moms FWD escape has pulled my explorer out the mud and even flat towed my ranger. And FWD bias is more efficent. Meaning better gas mileage. Doesn't seem like an oversight to me

I wish they at least gave you the option to have rear bias for towing as long as the driveline components are up to the task I don't see why they couldn't

 

[OffTrac]

Ugh I just went out and tested to verify, you're correct... Tow mod leaves the bias forward. Sand mode moves the bias middle (AWD), but even then it seems like a gross oversight on Ford's part. It certainly seems like the electronics are capable of moving the bias backward in Tow mode (which would make sense)

I doubt the rear axles were designed strong enough for that, especially under towing conditions.

 

[colintrax]

I wish they at least gave you the option to have rear bias for towing as long as the driveline components are up to the task I don't see why they couldn't

Well you do have sand mode, for the people that know it makes a difference

 

[13Sport]

Well you do have sand mode, for the people that know it makes a difference

except that sand mode has a whole different array of problems with towing. It disables traction control, trailer sway, and a host of other safety features that would likely be useful during towing.

It also only gets you half way there, it shifts the torque to all wheels, not the rear.

 

[Explorer0204]

Well you do have sand mode, for the people that know it makes a difference

Right, but because it isn't for towing do you think it could strain rear end components too much if they aren't rated for full use when towing?

 

[colintrax]

Right, but because it isn't for towing do you think it could strain rear end components too much if they aren't rated for full use when towing?

If so then why let you control the split in tow mode....
Only reason to use sand mode with a trailer is when traction isn't there. Like pulling a boat up a slick ramp. Get up the ramp and back to tow mode. No need for sand mode on cleanish asphalt a big rig can drive on.

Assuming you are a ME major you should know that low traction wouldn't put stress on the axles or other components. Least till you gain traction. If you're already moving and using your head (smart enough to know what sand mode does right?) then you won't have a problem with an extra 20%

 

[colintrax]

except that sand mode has a whole different array of problems with towing. It disables traction control, trailer sway, and a host of other safety features that would likely be useful during towing.

It also only gets you half way there, it shifts the torque to all wheels, not the rear.

I donno how to double quote and my phone is glitching. But read above post

 

[Explorer0204]

If so then why let you control the split in tow mode....
Only reason to use sand mode with a trailer is when traction isn't there. Like pulling a boat up a slick ramp. Get up the ramp and back to tow mode. No need for sand mode on cleanish asphalt a big rig can drive on.

Assuming you are a ME major you should know that low traction wouldn't put stress on the axles or other components. Least till you gain traction. If you're already moving and using your head (smart enough to know what sand mode does right?) then you won't have a problem with an extra 20%

Yea I see your point. I am just thinking of things like max capacity and long steep grades on the highway.

I'm sure the built in tolerances are enough like you said, especially when you are only using it for the necessary times you actually need traction. Just think it would be nice to have the peace of mind of rear wheel bias or true rear wheel even for things like turning up steep Hills on wet roads and stuff like that.

But.. Again.. If only the world were perfect!

 

[colintrax]

Yea I see your point. I am just thinking of things like max capacity and long steep grades on the highway.

I'm sure the built in tolerances are enough like you said, especially when you are only using it for the necessary times you actually need traction. Just think it would be nice to have the peace of mind of rear wheel bias or true rear wheel even for things like turning up steep Hills on wet roads and stuff like that.

But.. Again.. If only the world were perfect!

Personally I would want RWD to. But most people buying the 5th gen are more concerned with gas mileage.
Like I said my moms FWD escape pulled my explorer out the mud. I was in axle deep freshly plowed clay/topsoil. Truck came to a stop about 25' from an acess road. The road is DIRTY, covered in dirt and gravel that's washed onto it. Used a 30' rope and her little escape pulled me all the way to the road. Mostly antic free keep in mind my x weighs about 5,000lbs plus the mud. And fighting the mud it had to move out the way. But her escape is only rated to tow 3,500lbs. Oh and it doesn't have traction control. Just a powerful v6 and a momma that knows how to drive

 

[Kpwweb]

I don't think you understand how unibody and body on frame vehicles are made/designed. Unibody vehicles are safer

Not to mention more ground clearance where it counts!

I have both--lifted full frame pickup and EX... I guarantee inch for inch unibody has more useable clearance... Anybody who says otherwise hasn't been stuck on a rock...

Now you cant put 38s on a unibody... But if you put 33s on both, the unibody will have more clearance... Think rock crawlers are body on frame? Ha! They are tube frame--more like a unibody with distributed loads...

Some people will always be stuck in the live axle era...

 

[colintrax]

Not to mention more ground clearance where it counts!

I have both--lifted full frame pickup and EX... I guarantee inch for inch unibody has more useable clearance... Anybody who says otherwise hasn't been stuck on a rock...

Now you cant put 38s on a unibody... But if you put 33s on both, the unibody will have more clearance... Think rock crawlers are body on frame? Ha! They are tube frame--more like a unibody with distributed loads...

Some people will always be stuck in the live axle era...

I've already said unibody is thinner. But you can't compare a unibody vehicle to a tube buggy. Same idea but not even close. Good luck getting your unibody ifs irs out the woods

 

[Explorer0204]

Not to mention more ground clearance where it counts!

I have both--lifted full frame pickup and EX... I guarantee inch for inch unibody has more useable clearance... Anybody who says otherwise hasn't been stuck on a rock...

Now you cant put 38s on a unibody... But if you put 33s on both, the unibody will have more clearance... Think rock crawlers are body on frame? Ha! They are tube frame--more like a unibody with distributed loads...

Some people will always be stuck in the live axle era...

I will be stuck in the live axle era my whole life!!

It's just how I was born and raised man, I would change if I could, but I'm just the kinda guy that hears a v8 roar off in the distance and smile. I am who I am.

Is it a bad time to tell you that I also love my Harley Sportster with its now 35 year old engine/trans design and carburetor. Hehehe

 

[Explorer0204]

I've already said unibody is thinner. But you can't compare a unibody vehicle to a tube buggy. Same idea but not even close. Good luck getting your unibody ifs irs out the woods

I agree. The idea is the same. In application.. Nah.

Go to any jeep forum and ask them what they think of the Unibody grand Cherokee for off roading... I'll wait...


Yea, that's what I thought, they ALL hate it.