It's hard for me to say, because I had the gears done within about two weeks after I put my suspension lift on and went to 35's, so I didn't have much to go by. But I'd say I gained about 2 mpg in town, about the same as stock up to about 65 on the highway, above 70 or so, I prolly lost between 1 & 2 mpg's...

 

Looks like I have the 3.92 gears. I emailed Dodge for the specs:

"In response to your email, we would like to inform you that your vehicle
was equipped from the factory with the following:

Leather Trim 40/20/40 Bench Seat
Taupe
Trailer Tow Group
Quad Cab Lone Star Value Group
Monotone Paint
4.7L Eng (EVA)/5Spd A/T 5-45Rfe(DGQ)
136 Amp Alternator
700 Amp Maintenance Free Battery
4 Wheel Disc Rr Anti-Lock Brakes
40/20/40 Split Bench Seat
Front Height Adjust Shoulder Belts
Next Generation Front Air Bags**
Front Seat Area Carpet
Front Floor Mats
Passenger Assist Handle
Rear 60/40 Split Folding Seat
Rear Underseat Compartment Storage
Overhead Console w/Trip Computer
Front Center Seat Cushion Storage
Folding Flat Load Floor Storage
All 5-Speed Automatic Transmissions
5-Spd Automatic 545RFE Transmission
Lock-Up Torque Converter
Man Shift-on-the-Fly Transfer Case
205MM HD Front Axle
3.92 Axle Ratio
Corporate 9.25 LD Rear Axle
Anti-Spin Differential Rear Axle
All Gas Engine
4.7L V8 MPI Engine
Tinted Glass Windows
Rear Sliding Window
Rear View Auto Dim Mirror
Passenger Side Sun Visor w/Mirror
Power Trailer Tow Mirrors, Fold-Away
All Vehicles W/Power Mirrors
Remote Keyless Entry
Air Conditioning
Dash Liner Insulation
Floor Tunnel Insulation
Route 87 - UP, San Antonio, TX
Instrument Cluster w/Tach
120 MPH Primary Speedometer
Var Intermittent Windshield Wipers
Cigar Lighter
Dual Note Electric Horns
12V Auxiliary Power Outlet
Power Locks
Power Windows, Driver One-Touch
Power 6-Way Driver Seat
Power Driver Seat
STRIPE/BADGE/MOLDING/COLOR
STRIPE/BADGE/MOLDING
Glove Box Lamp
Halogen Headlamps
Fog Lamps
Cargo Lamp
Bright Rear Bumper
Body Color Upper Fascia
Bright Front Bumper
Front License Plate Bracket
Bright Grille
Black Windshield Moldings
SLT Badge
Dodge Badge
4X4 Badge
Removable Tailgate w/Caliper Latches
Front Air Dam
Front Bumper Sight Shields
Federal Emissions
EVAP Control System
26 Gallon Fuel Tank
Auxiliary Transmission Oil Cooler
Speed Control
Heavy Duty Engine Cooling
Next Generation Engine Controller
Graphite Metallic Clear Coat
Graphite Metallic Clear Coat
All Radio Equipped Vehicles
AM/FM Cassette Compact Disc Radio
Infinity Speakers
Fixed Long Mast Antenna
Power Rack and Pinion Steering
Leather Wrapped Steering Wheel
Front Heavy Duty Shock Absorbers
Rear Heavy Duty Shock Absorbers
Front Stabilizer Bar
Tilt Steering Column
Full Size Spare Tire
Tire Carrier Winch
P275/60R20 BSW All Season Tires
Goodyear Brand Tires
20X9.0 Aluminum Polished Wheels
20" Steel Spare Wheel
All Aluminum Wheels
Center Hub
Pickup Box
Class IV Receiver Hitch
7 Pin Wiring Harness
Trailer Tow w/4-Pin Connector Wiring
Build To U.S. Mkt. Specifications
Manuf Statement of Origin
Without Billable Fuel
Spring - Left Rear
Spring - Left Front
Spring - Right Rear
Spring - Right Front"

 

I see from your "build sheet" that you have the factory LSD. Is it still in there? How many miles on your truck? Just curious, because most '03s have had the factory LSD grenade their rear ends by now...

 

How can i get a build sheet for my truck? Just curious about all the specs.

 

On the Dodge Truck site, there is a section for current owners (top right I think) from there you can hit a button to contact ask customer service. make sure you got your vin# handy...

They'll usually respond to your request via email in 24-48 hours...

 

I don't know what was done before I bought the truck. I bought it with ~88k on it and it now has ~92k

What will the grenading feel like? Will it still be drivable?

 

Sit down and do a search here for LSD or maybe even better "c-clip" you can even Google "c-clip failure" and get a gajillion hits. Some are lucky and discover pieces of a failed c-clip when they have the fluids changed, while others kinda notice the issue when they get into the ring & pinion and basically have the pumpkin explode!
The first instance, the truck is pretty driveable, the second, not so much...

 

I do have buddies that are wrench heads, just havent talked to them when this topic came up... I figured it wasnt very easy, plus specific tools needed.... I just wanted to know from guys that have worked on the Dodge... Plus I was wondering what Kinda $ would I be looking to spend from a shop just in labor? I'll buy the parts.

I Have 3.55 gears with LSD with Low miles... only 20k, and its a 4X4

 

I checked my glove compartment today and saw that i have a corporate 9.25 anti-spin with 3.92 ratio. Also the front is 205mm. I tried to read the rest but all i could make out was something about the transmission. The rest is kinda faded out. I am happy to have the 3.92 gears. Really am satisfied with my first week owning this truck.

 

yeah, just keep an eye on that factory LSD...