Pick your brains - difference in rear Axles

Steadfast · Post by **Steadfast** » November 17th, 2008, 7:45 am

looking at 2009 Ford 250 model 4x2 SD Regular Cab 137 in. WB SRW XL
(5.4L V-8 Cyl 6-spd man w/OD) & am also thinking of auto tranny (do I need it? I driven clutch for a few years but never towing an item.)
http://autos.aol.com/cars-Ford-F_250-20 ... 20w/OD:V-8

In rear axle (vehicle) comes with a 3.73 Axle Ratio. I want a limited slip, which of the 4 is best for this model & what are the differences I am looking at, in power &/or ability? (no smart aleck remarks on the money being cheaper please)

have 4 options;

Limited Slip w/4.30 Axle Ratio - $50

Limited Slip w/3.55 Axle Ratio - $300

Limited Slip w/3.73 Axle Ratio - $350

Limited Slip w/4.10 Axle Ratio - $350

Slowpoke · Post by **Slowpoke** » November 17th, 2008, 8:05 am

The lower the numbers, the higher the gears. In other words, the 3:50 ratio will have the engine turning fewer RPM then the 4:30 at the same speed. The lower numbers will give you better fuel economy, and the higher numbers will give you better pulling power. With the price of fuel, the lowest number you can get and still pull the weight you want to pull is your best bet.

Rangerguru · Post by **Rangerguru** » November 17th, 2008, 8:11 am

The 3:73 is probably your best bet, it will give you decent fuel economy and when you need to tow something, it should do very well with that too especially if you are going with the manual transmission.

McD · Post by **McD** » November 17th, 2008, 8:14 am

I'm no expert but I'll through out a few things.

I assume you want to tow.

The lower the ratio the less "Pulling" power it will have.

3.55 best mileage worst for towing, your trany will be shifting a lot.

3.73 good mileage kind of a "Standard" on trucks. Ok for towing but if your hauling a real heavy load (near wght limit) there will be some strain on engine and shifting in tranny..

4.10 will have good pulling power but you will pay in your mileage

4.30 I'd stay away from this one unless you plan on running 1/8 mile drag races.

My truck has a 3.73 in it and it does OK. I like it since I only tow a few times a year so most of my driving is empty.

I like the automatic myself.

If towing Stead... make sure you check out the weight limits for your truck/engine against what your might want to tow. To big a truck can tow light, to small a truck can't tow heavy.

4x4 gives you a little extra tow capacity also.

Just my take lets see what others have to say.

RRDTm3 · Post by **RRDTm3** » November 17th, 2008, 8:28 am

Not that I work for GMC.
After looking @ the MSRP for the truck I have to say.............................I just bought a GMC Crew Cab loaded leather, on star, XM the whole ball of shit for $22,500. I got the big V-8, tows like a mother and it drops to a 4 banger on the HWY. I got a 22 gallon tank and get 400 miles to the tank on the HWY

BadMuther · Post by **BadMuther** » November 17th, 2008, 8:31 am

RRDTm3 wrote:Not that I work for GMC.
After looking @ the MSRP for the truck I have to say.............................I just bought a GMC Crew Cab loaded leather, on star, XM the whole ball of shit for $22,500. I got the big V-8, tows like a mother and it drops to a 4 banger on the HWY. I got a 22 gallon tank and get 400 miles to the tank on the HWY

That's awesome Bubba! Post a pic foo!

Stead, one piece of crucial info is what size tires are on it or what size tires do you plan to run? Affects the gear ratio.

RRDTm3 · Post by **RRDTm3** » November 17th, 2008, 8:45 am

pic to follow

ANGRYCivilian · Post by **ANGRYCivilian** » November 17th, 2008, 9:18 am

Which tire size are you going with? That should also be factored into choosing gearing.

The largest stock tire is 265/70-17, or 31.6" tire. The 3.73 will give you better economy, but the 4.10 would be a decent match for that tire size.

Now, as to how this relates to towing, I don't know.

Ranger Bill · Post by **Ranger Bill** » November 17th, 2008, 9:52 am

Jake, the issue is how often and how much you will be towing. Do you plan on pulling 10,000 lbs. on a regular basis or half that much or less once in a while?

GoldCoast · Post by **GoldCoast** » November 17th, 2008, 12:08 pm

I don't tow every day, but I do like to work on old cars and that leaves me with a trailer on my truck several times a year.

I really prefer to tow with a manual transmission. They make all the difference in the world when you're driving through hilly terrain.

The other 95% of the time I prefer an automatic because I'm lazy and like every other Ranger on the board, my knees hurt.

Unless you're towing a yacht or a monster truck or a four horse or more trailer stay away from the 4.10 gears. 3.73 will be sufficient, esp with a manual transmission.

Rock Island Ranger · November 17th, 2008, 12:37 pm

I guess my real question would be....why a truck? Do you actually NEED one?

Rangerguru · Post by **Rangerguru** » November 17th, 2008, 1:39 pm

Rock Island Ranger wrote:I guess my real question would be....why a truck? Do you actually NEED one?

Who doesn't. :?

RRDTm3 · Post by **RRDTm3** » November 17th, 2008, 1:53 pm

Rock Island Ranger wrote:I guess my real question would be....why a truck? Do you actually NEED one?

Holy shit! This coming from the owner of one of sweetest trucks I ever rode in!

Rock Island Ranger · November 17th, 2008, 2:06 pm

Rangerguru wrote:
Rock Island Ranger wrote:I guess my real question would be....why a truck? Do you actually NEED one?
Who doesn't. :?

Ok my son, thou should taketh notes.

YOU: Live in Georgia, live in the rural area, have dogs, kill animals, tote numerous guns, probably have some livestock, haul wood, dirt, and other things including dead animals. Everyone you know or want to know drives a truck.

UNCLE STEAD: Lives in New York City and none of the above applies.

Questions?