i know its been posted a bunucha times but i cant seem to find the threads. so how can i tell which gear ratio i have? i think i have 4:10's cuz doing 65 im right at 2000 rpm and i would think i would be at a lower rpm? if im correct and i do ahve 4:10's ...these r "pullin gears" right? could this also be why i get bad fuel mileage? i like to hover around 70-80 on the highway which means my r's are higher. i filled up today and did a hand calculation...13.2...over head says 14.8-15.1

 

My truck has the 4:10 and runs 2000rpm at 60 but its a 6spd.At 75 shes screamin and gets about 16.4 but it has 89000 miles. Sounds like a 4:10 and yes its for pullin and they like it!

 

Look in your glove box. There is a sticker in my glove box that gives the details about engine/trans/gears.

BTW I get 19.1 highway (hand calculated) with my 4.10 gears at around 65. 39000 miles on the engine.

 

ill check the glove box...but wow why am i getting such sucky mileage? i do more around town driving thann highway driving but when im on the highway i get maybe .1-.4 mpg's better. i have almost 70,000 miles. any suggestioins??

 

yup...i have 4:10's .....anyone have and ideas for the fuel mileage problem?

 

That 4;10 gear was disigned for pullin, I have the same gear. Just take it easy and you should average around 15-17. the first few months i had my 04 3500 I didnt get $^%# for mpg cause I couldnt get enough of kikkin it around. Now that Im used to it and treat it better the mpg"s have improved.

 

Mix up some Drew Brew and drop in a K&N it will do better, alot better if you stay out of it.

 

Here's the deal if you are even considering a gear swap to get better MPG.......

Swapping gears for MPG is like ordering a Diet Coke with a king size Double Whopper meal, it'll never pay off.

Figure this (double it for a 4x4)

Gear set: $150 - 200
Install Kit: $100 - 200, depending on the level of kit you get
Labor: $300 - 600 per axle, unless you know how to do it yourself. Little hint, this IS NOT a beginner job. You need a few special tools to do it right and you can screw it up real easy.

So, for a 2wd truck, you would be looking at $550 - 1000 dollars to do a gear swap. That's a lot of fuel to recoup. Double that for a 4wd.

Best bets to getting some mileage

1 - Lose the un-needed weight. All that crap in the toolbox that you NEVER use. Get rid of it.

2 - Run your tires at the max inflation that still gives you good wear.

3 - Change your air / fuel filters. Not necessarilly to a high flow air filter, as this means more air. More air = more fuel.

4 - Drive like you have an egg under your foot.

5 - Try to keep the engine in the meat of the torque curve at highway speeds. Above 2K and your making a good amount of boost. Boost = Air = Fuel = Poopy MPG.

 

Hey Rich, you get a new truck yet?

 

Actually, I just got a call from Dodge this morning. They wanted to try and "work something out". My response, "You've had 14 opportunities to work something out, now it's time to make the final fix. Replace it or repurchase it, you have 27 days left."