Im a n00b when it comes to trannies. My truck is a 4x2 4.2L V6 and I dunno what my gears are. Whats with all of these guys swapping gears and what not? What do higher gears do to your truck and how do I find mine?

 

Changing gears is like shifting gears on your mountain bike. If you go with a lower gear (smaller sprocket) it's easier to peddle when you start out slow. However, when you start going faster you have to peddle like a mo fo to keep up to speed = you get tired.

Going from say a 3.55 rear end to a 4.56 rear end (on stock tires) will give you more power when you start out (smaller sprocket) but you'll be winding out more RPM's at higher speeds = reduced fuel economy.

Most people change to a lower gear when they get larger tires (35" for example) because it's harder for the truck to start moving with the stock gears (3.55, 3.73) so by changing to a 4.56 or 4.88 gear it brings it back close to the stock ratio.

Make sense at all?

Oh, it should say on your rear differential cover what gearing you have.

 

On stock or smaller tires, I wouldn't go any higher than a 4.10

 

Ohhhh.....okay! Thanks! I'm not all up for going outside in 47-degree weather in just boxers and crawling in cold-a$$ sand and under my truck which is mostly metal and also cold just to see three numbers and a period. I'll be the more sensible one and wait until tomorrow Thanks man.

 

Uh-hum, Mr. Not-So-Sensible went out and snapped this off:



So, I'll let you guys examine this while I go light up my fireplace....BRRRRRR.....

 

check the door jamb sticker and tell me the axle code and I can tell ya what it is

Better Yet:
19 — 3.55 non-limited slip — F-150
25 — 4.10 non-limited slip — F-150
26 — 3.73 non-limited slip — F-150/Mark LT
27 — 3.31 non-limited slip — F-150
B5 — 4.10 limited slip — F-150
B6 — 3.73 limited slip — F-150/Mark LT
H9 — 3.55 limited slip — F-150
18 = 3.08 non-limited slip — F-150

 

A little bigger than stock tires, I'm riding on Michelins w/ 16" American Racing.

 

Cool. 19.

So, 3.55's on a non-LSD. Figured.

Is that good for gas mileage?

 

what size tires? I'd up to at least 3.73 LSD, maybe even 4.10 LSD. You're only going to lose maybe 1-2 miles per gallon with the 4.10's

 

going from 3.55 to 3.73 is a total waste of money, youll never notice the difference