warriorcustoms

iTrader: (10)

Id like to start with 4L60E cars but T56 info would help too!!!
My S10 ext cab has 4.10 posi front & rear on 315/75/16s thats close to a 35" tire... It works out to a 235/75/ with 3.42 gears & at 70mph its turnin right a 1951rpm... Anything Under 70 feels like it luggin a bit & if Im in town at 45ish I pull it into 3rd... Im thinkin about 4.56s since itll work out close to a 3.92 with stock tires on an LT1 car... But I know Capricemgr (sp) says a few guys have 4.10s on stock tires & get Better milage or even guys just using Drive to get better MPGs... I know My junk needs a Tune but hearing guys say 24mpg with a 4L60E has Me a little unhappy at maybe 15mpg lol
So post up MPGs with Gear Ratios & RPMs at the MPH kinda deal... Thanks in advance guys!!!
Motor specs are 355" 6.0 Hbeams & Mahle forged flat tops with an Fbody cam & Iron heads because 1 of the aluminum LT1 heads had cracks... I still gotta finish porting aluminum heads before that gets swapped & the new motor is right at 3000 miles if any of this helps... Oh with blue 24lb Ford Denso injectors...

Cajun ELESS-ONE

i have 4.11s through an auto. get about 15mpgs if i stay out of the gas

hrcslam

Your 4X4 S10 on 35" tires will never see 24mpg. Not even with a diesel 4 banger out of a VW with the cheat devices installed.

MPG is the result of fuel used to make the needed (and only needed) power to maintain the vehicle at a certain acceleration or constant speed. The heavier the vehicle (truck), the more rotating mass (4x4), the less aerodynamic (truck, 4x4), the more power you'll need to maintain any given speed; and that goes up tremendously as speed increases in regards to aerodynamics. Want better fuel economy? Ditch the 4x4 and lower the S10 to the ground. Put on some 17 inch wheels with 26" tires and run some 3.42 behind the 4L60e. You should see,close to 20-22mpg highway after that.

It's all about how much power you need vs how much power you're making and how much fuel you're using to make that power.

15mpg isn't so bad actually, for your set up.

SS RRR

iTrader: (2)

final drive radio has little to do with mpg. those who say they get worse gas mileage from installing differentt gears are the ones who have their foot in the gas as often as possible for that "SOP, broh..."

warriorcustoms

iTrader: (10)

A guy on S10extremist has a square body reg cab long bed with Dana 44s & if I remember right a 4spd manual & np205... He stated 24mpg!!! Thats part of the reason Im asking!!! LT1s have a sweet spot for MPGs & I didnt get to drive the T/A because it was blown up when I traded for it!!! And I know the whole Dog on it I get 12mpg & if I take it easy I get 15mpg LoL All Thats not what Im askin for!!! Hell guys do solid axles on stock 4.3 S10s rollin on 35s & gain MPGs with 4.56s!!! Thats why My Blazer will get 33s & 4.30s or 35 & 4.56s... Im askin this to Find the RPM range thats the sweet spot on an LT1... Keep the replys comin & the S10 isnt gettin Lowered!!! Itll stay on 35s but if the info points toward 4.88s instead of 4.56s to get the Highway cruising speed then thats what I will do!!! Luggin a motor can kill MPGs as well as Turnin Too Many RPMs!!!

Shownomercy

iTrader: (1)

Summer fuel, and my 3/4 ton will pull 20mpg mixed driving on a larger tune. I am on 32s though.

Do you have a wideband or EGT? Without either you are gonna be guessing.

bowtienut

iTrader: (1)

IMO, going from 4.10 to only 4.56 does not justify the cost.

Not putting you in this category, but anybody that thinks they'll recover the cost of the gear change, especially on a 4wd, in fuel savings is kidding themselves.
BUT....... change them to 4.88's and it will certainly be more pleasing to drive

There is no one sweet spot of rpm in any engine for fuel mileage. That rpm will change depending on the load on the engine. The lower the load, ie. like an aerodynamic lightweight car cruising down the interstate, the lower rpm it will want for best economy. A brick such as a lifted 4wd on big high rolling resistance tires will want a lot more overall gearing even if using the same engine.

warriorcustoms

iTrader: (10)

I know gears cost a lot if Your buyin both brand new & payin someone to install em!!! Ive built everything on this truck So thats not an issue... Im gonna swap out the rear diff for a 98up Rodeo D44 thats 63in wide & has larger disc brakes plus a bigger gear set The Rodeo Dana 44s come with 4.10, 4.30 & 4.56s... Dana 44 High Pinions dont come with 4.30s or does the aftermarket make them for a high pinion!!! You can use D50 gears & bearings but youve gotta grind the housing & Im not makin it weaker!!! SO if the 4.56s will net 1 or 2 MPGs I will get them Plus a Tune to have a Better Performing Truck!!!
I looked up Ole Boys build & the Only 2 differences are He has an NV4500 5spd with .73 overdrive & the stock Iron head cam... So if his Math is right & its a true 24mpg Plus Heavier parts the weights pretty close... Is the Fbody cam eatin 9mpg LoL
Im not tryin to build a Hot Rod with this one Just a Good Daily thatll do everything I want The 396 parts settin in the shop are for the Hot Rod I can see it gettin 12 to 15mpg LoL or maybe 10... Keep the replies comin!!!

4K+Converter

My old Camaro only got 12mpg, and dropped there after I put a torque converter in the car. If you need a tune like you said, I'd do that first. Then you can focus on the drivability part of the tune, especially the rpms you cruise at with your current gear set.

97pontta

iTrader: (10)

My car is a T56 with 4.33 gears on a 295/35-18 tire and can get 24-25 MPG on the interstate cruising 65-80 mph . Driving the car hard only a little here and there and that number drops quickly.