coggonobrien

looking to regear due to loss of power towing, loss of fuel economy and constant shifting on hills when driving 2lane highways. Just wondering what folks would recommend. Currently have 3.73 with 295/7r18 nitto's. Would also like to swap some sort of locking or limited slip diff in the rear end while it's open. By the math it looks like a 4.0 ratio would be the equivalent even though it obviously doesn't exist. Would people recommend a 4.11 or take the jump to 4.30. also anybody out there with this setup that could tell me how their fuel economy is post swap. Truck has a 2.5" hbs level with procomp add a leaf. Also just to verify it should be a 8.8" front pumpkin and 9.75" rear right?

Thanks!
David

Manuellabour247

As a rule of thumb you want to go two gear sets for the benefits. I know there's a formula on one of these threads by the guru's showing what gear set you need to return to the stock feel of the power. I just can't remember it right now. Been a long day. Good luck.

BassAckwards

AFAIK they don't make a reverse cut 4.30 for our front axles or I would have already done that so you will have to stick with 4.10s however given you already have 3.73s the cost of the job wouldn't be worth the gain to only go to 4.10s. You should go with 4.56 to make it worth your while, but that will put you in a lower overall final drive ratio than stock.

coggonobrien

any guess how much of a mpg hit i would take with the 4.56's? Most of my driving is 60mph. Currently getting 15-16

Manuellabour247

You should slightly gain mileage in town, but will probably lose 1-2 on the highway. Driving 60 is about the best speed to drive for optimum mileage. I know a couple people locally that have picked up mileage with their gear swap, but they drive mostly city with minimal highway.

BassAckwards

This