kerndog5.3

Ive got a ECSB 5.3 with mods listed below and stock 3.42's and was thinking about getting 3.73's and was wondering how much my MPG would change if any. Right now i get about 12.5 in the city and 16-17 on the highway. Also if I did change gears then should I get a locker also?

Rhino79

iTrader: (7)

You will probably not even notice a difference in mileage. I would do a good posi unit when I did the gear swap. Where you start noticing some mileage loss is with a stall.

spitfire2332

wtf, how is your driving habits? I get about 12.5 city

NeverSatisfied02

iTrader: (12)

Where do i find out what gears i have? I dont even know. lol

Mr. Sandog

What size tire do you run?

What speed do you normally cruise at?

How much of your driving is freeway and how much stop and go (i.e. 60% freeway/40% stop and go)?

TouchOfEvil04

iTrader: (13)

I don't understand how guys get such bad gas mileage...unless you have large tires then it makes since.

NeverSatisfied02

iTrader: (12)

I get 16.1 MPG in mine runnin 22's and driving alot in the city. I probably get 18-20 on the highway.

jblack6527

on my truck, a 2001 ecsb with a 5.3, and 20" SS wheels, i got about 16ish in town, and 22-23 highway, with a 3.42. I swapped in a 3.73, my in town went up just a fuzz, (maybe .5 mpg) and the highway dropped about 1 mpg.

jblack6527

look in your glove box, there should be a code
GU6=3.42
GT4=3.73
GT5=4.10 and a G80 indicates a locking Diff.

Bowtie70SS

iTrader: (10)

Supercharger + 6.0 + Stall + Factory 20's + Lead foot = Bad mileage.

Although for a 500hp 5750lb truck 15 avg city/highway isn't bad