Rear end ratio on 2007 Expedition
 

Guys,

New the forum. Have had Fords in the past. My first was a 1956 Fairlane club coup with a 1957 312 engine and two four barrels. Wish I still had it. Most recently I had a 1990 Bronco and 1998 Expedition. Loved them both. Right now I'm driving a Dodge Quad Cab Hemi. It's almost as much fun as the 56 Fairlane. Bought the Hemi cause it really hauls.

It's time to trade and I know that no way will an Expedition match the Hemi's performance, but I think that I would be better off with a SUV than a pickup right. The new Expedition appears to "fit" me better than the other SUV's on the market.

To get half-way decent performance, I think that I need at least a 3:55 or 3:73 rear end. What's available on the new Expedition? I plan on buying the base XLT and about the only option I will add is the trailer tow package.

Two more questions: 1) Why no locking rear differentlal as an option? 2) Where can I find information on the new six speed transmission? (I had my 1990 Bronco in the shop three times for a transmission rebuild all under warranty. Yep, I'm pretty patient.)

Thanks.

Tom

You didn't mention 2 or 4WD. A 3.31 axle ratio is std on the 2WD, a 3.73 on the 4WD- there are no options for either. The new six-speed has a deeper low than the previous Automatic, so axle ratio is only one factor in determining the performance of the new Expy.

The std. Advance-trac, which is essentially a 4-wheel electronic anti-skid control, is not compatable with a locking differential. It also makes the locker unnecessary- four wheel anti-skid/traction control vs. 2 wheel mechanical with the locker.

The six-speed has already been in service in the Lincoln Navigator, so the Lincoln website may give more info on this transmission.

I thought I had heard that the 6 speed going into the MY 07's was a different and newer design 6 speed than the current one in the navi...but I could be wrong.
Marcus

Polarbear,

Thanks much for the information. I'll be going with four wheel drive. I thought that Advance-trac might be taking the place of the limited slip differential.

Tom

The 3.31 rear axle is STANDARD on ALL (4x2 & 4x4) Optional 3.73

The EL's come Standard with the 3.73 rear axle

I read your other post relating to this and I have to disagree, at least on the 07's. I have the actual build sheet for my vehicle (4 wd - xlt) and it clearly shows 3:73 is standard. That is also what is required to tow 9000 lbs. I did see that the 2 wd versions can go to 9200lbs.

I have not tried to tow this load yet, but this is why I bought this truck. Others here have mixed feelings about this but many seem to feel it will tow just fine.

Edited - I just noticed that most of these posts are old- I hope you have some luck Semper finding someone out there with 3:31's.

Ya beat me to it... ;)

-- Chuck

Great minds....:) :-D

When we purchased our 08 XLT 4x4 the 3.73 was the option and the 3.31 was the standard.

I think Semper has the 08 so he is correct for that year. What the 07's came with I have no idea.

Tmod

Chevy24d, Chuck S, & Tmod700,

Thank you

I failed to clarify that I was refering to the 2008 model.

2007 came standard with the 3.73, right?

My 08 has 3.31. Standard. $75 add for 3.73. I hope I'm happy with the performance. It was built last monday, yes gate release, no ship. Anxious to see it next week I hope.

Quote:

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Originally Posted by SemperFiDevilDog

The 3.31 rear axle is STANDARD on ALL (4x2 & 4x4) Optional 3.73

---

Since SemperFiDevilDog posted the 3.31 & 3.73 question about a dozen times, I looked for a 2008 build sheet. I had to register at blue oval forms to down load one. Here's the statement for the 2008's, and yes its different from 2007.

3.31 axle was made standard on 4x4 Expedition (non-EL), similar to 4x2. 3.73 axle is available as an option (X16)

Basically, per the order guide 3.31 (X15) is standard for non-el 4x2 or 4x4. The 3.73 (X16) is standard on EL's and SSV (Special Service Vehicles - Police etc). The 3.73 (XH6) LIMITED SLIP, is only available on the (17L) EL Limo Prep package.

Ford sells the 3.31 rear as Standard equipment on ALL 2008 Non-EL models. For an added $75 you can get the 3.73 rear (option only).

The 3.73 is standard on ALL EL models.

Only the 3.31 rear (with HD Tow package) will give you 9,200 max towing (4x2 or 4x4).

The 3.73 (with HD Tow package) only rates at 9,050 on (non-EL) models.

with Tow package 9,000 (4x2 EL)

with Tow package 8,750 (4x4 EL)

without Tow package ALL 2008 Expeditions Only have a Max Tow of 6,000

Semper I think you got a little confused on your statement in a couple places.

From Ford's Site.

http://www.biosmedic.com/images/08expedition.jpg

Tmod

Tmod - I see the change in 08 vs 07's. As I said in my post, the 07's were std w/3:73 and the title of this thread was 07 Expedition so that is why I commented as I did. Sorry for the confusion.
I will admit it seams strange to me that a lower gear ratio would have a better tow rating.......