Lower Final Drive

[SionisPrioratus]

Hello and thank you, I am a new person in this forum. I have Frontier 2K, V6 3.3 Automatic 4 speed overdrive, Crew Cab, 200,000+ miles, great truck. Just one issue, very poor mileage, and since now gas in Florida has 10% ethanol it has gone down even more. I was at my local Nissan parts dealer talking with one of the mechanics about the low fuel consumption, I wanted to know if I could replace my transmission with a 5 speed one. His answer: NO...But, he mentioned that I could replace the Lower Final Drive (Drive Pinion & Ring Gear) from a 4.625 to a one much lower. I did find one that is 2.937 but he was not able to say for sure if it will fit my current transmission. The premise is that with a lower gear when I am at 70mph wont be a 3K rpm's, but much lower RPM's, which will increase the miles/gallon. I am about to start a new job, and I will be driving a lot. So I need every bit of an edge that I can get.

Could you please advise if the 2.937 is a good fit for my Frontier?

Again, thank you

SionisPrioratus.

[longtooth]

Never changed the final gear in the transmission. Always did the diffs.

[SionisPrioratus]

Thank you so much for taking the time to reply. but, could you be a bit more specific????

Again, thank you...

SionisPrioratus

[longtooth]

Diffs is short for differential where the ring and pinion are.

[SionisPrioratus]

Thank you for your reply. I did fig. that Diff was for differencial. I was hoping for a suggestion on what type of Diff to look for. If you could point me in the general direccion I really would appreciate that.

Regards,

SionisPrioratus