Rear End Question

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Nov 15, 2006 | 02:26 PM

DKilleen

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From: Waskom, TX

Rear End Question

While waiting for service at my local dealer, I started looking at the new '07s. The practical angel on my left shoulder says that a 250 has all the towing, carrying power that I need....and that's true. I have an '03 250 PSD now, and it does what I need it to do. However, the devil on my right shoulder thought that the duallys sure did look nice. ;-) A question on something that I noticed while looking at the stickers. All of the 350's had 4.10 rear ends. My 250 has 3.73 gears and pulls everything I need and does a great job. Any trailer towing I do (and I do a lot of it) is limited to a trailer that has a GVWR of 7,700#, and maybe 2,000# in the bed of the truck. If I understand gearing correctly the 4.10 would come away from a stop faster, but would also run at a higher RPM on the highway which would use more fuel. I see from the Ford site that you can order a 350 with 3.73 gears. I think that in the long run, considering the fact that fuel isn't going to get cheaper, if I'm going to go ahead and get the 350 that I should spec it with 3.73 gears.

What do you think?

Thanks

David Killeen

Nov 15, 2006 | 02:31 PM

Ace!

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Joined: Nov 2004

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From: So Oregon

It depends on the engine and at what RPM it runs the most efficient. 4.10 doesn't have to be more inefficient fuel-wise (although it may be). The 4.10 will run at a higher RPM at any given speed than the 3.73, but if you drive at a certain speed, say 65mph, the 4.10 may be in a better place in the RPM range, torque curve than the 3.73 and you may get better mileage at that speed. It's a crap-shoot whether you would see a increase or decrease in mileage. I *think* though the diesel would probably work better with the 3.73, unless you change tire size to a taller tire.

What kind of last name is Killeen?

Nov 15, 2006 | 02:42 PM

DKilleen

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From: Waskom, TX

Thanks, Ace. Yep. It'll be a diesel.

Killeen is Irish. I was told growing up that there is a Killeen Castle over there. When I went, I found it was just a ring of stones in the ground. :-(

Nov 15, 2006 | 03:42 PM

Ace!

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From: So Oregon

Yeah, I was kind of funnin'. That last name is a dead give away. I can't imagine a name more Irish looking than that. I also see online there is a Killeen, Texas. You must be a pretty important guy to have a castle in Ireland and a whole town in Texas named after you.

Good luck on the truck. These Fords are d*mned nice.

Nov 15, 2006 | 03:50 PM

Dsl Lover

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From: Northwest OH

Previously, the 3.73 was the only option for the diesel. The 4:10 was for the 5.4L or V-10. I do not think that is still the case.

The thing is, you can get a properly equipped Superduty to tow 19,200lbs, which is probably where the 4.10 comes in, in addition to the tow command, etc.

Nov 15, 2006 | 04:08 PM

blackhat620

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Joined: Dec 2003

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From: Arizona

DKilleen,

If you are looking at a 2007 6.0 PSD with DRW then they either come with a standard open diff 3.73, or an optional 4.10 LS. You can also get a 4.30 LS if you get the Tow Boss Package.

The 2003-2007 6.0 PSD with SRW is only available with the 3.73 rear axle either open diff or LS.

BTW you can no longer order 2007 SD. So if you want one you will have to buy from dealer stock.

You can now order the 2008 SD with the new 6.4L PSD, they will ship after January 1, 2007 and the prices are not available yet.

Hope this helps

Nov 15, 2006 | 04:24 PM

DKilleen

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Joined: Mar 2005

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From: Waskom, TX

Ace, I've been to Killeen and unless you're in the Army, you're a minority. Fort Hood is there. Nice town though.

Dsl Lover, it sounds like the 3.73 is what I really want. I know that the F350 can be spec'ed to pull some hellacious loads but I just don't need that. I'll never pull more than 12,000#.

I forgot about that new engine, blackhat620. No way do I want to be in the first year for a new engine. Looks like I'll wait awhile and see how that 6.4 shakes out.

Thanks,fellas for your help. I found what I needed.

Take care

David