a buddy of mine is telling me not to get 4.10 gears because...

he says my top end will suck, and 3.73 will do me better.

and 2 he my gas mileage will be worse, which i know is true but how much worse? You see i'm still a daily driver but i don't mind takeing a few for the team if it'll help out my cars performance.

So is this true, will it kill your top end and destroy your gas economy?

 

4:10 = 20% higher rpm

3:73 = 13% higher rpm

stock 3:27s 5th grear @ 75mph = 2000 rpms
@ 90mph = 2600 rpms
@ 105mph= 3100 rpms
i think its something like that correct me if im wrong its been a few times i was going 100 and looked at the tack. it might be lower than that @ 105. i know the 75mph is correct. bottom line what ever rpm you hit at 4800 in 5th that will be your red line with 4:10s. i dont have 4:10s but thats what i figure.

5th gear will be more of a working gear you will still be able to most likely hit 150mph

 

It's garbage. With your 94+ 5 speed tranny, it's geared so crappy that 4.10's are needed to see much of a difference. Countless people swap in 3.73's and swap them out for 4.10's and say why didn't I do that the first time?

Around town, if you short shift you could actually improve your gas mileage.

 

Everybody's always worried about top speed when getting lower gears, but honestly, how many times do you drive 150+ MPH? There's never a reason to go that fast, unless you're in the Indy 500 or you're ripping an 8-second pass in your drag car. On the street, low gears do a world of good because they pull you through the power band a hell of a lot quicker, so you get to your desired speed much faster. Often times guys with really low gears will leave from a stop in 2nd, then shift right to 4th, then cruise in 5th. You probably won't notice much of a difference if at all in your gas mileage, but you sure will feel it on the butt-o-meter.

 

hes right about the gas mileage just cruise in 5th instead of 4th. your not really gonna loose that much gas mileage in a 5speed

 

Also with 4.10's, your engine won't have to work as hard to get to a desired speed. It'll be revving up faster and you'll be shifting quicker, but the engine won't be under a load as much to get moving. It's probably better on the engine the lower the gears you have.

 

rule of thumb....if you have a 4.6 then go no less than 4.10's.
the 4.6 revs higher hence the steeper gear

 

i had 4.10 in my 99 cobra after 800 miles changed them to 3.73s ,,,,,here it goes not a big diff,,but i would like lower rpms on the highway for long distance driving like ...with 4.10s @ 3000 rpms you are going 82 mph,,,,with 3.73s @3000 rpms you are going 92mph you make the choice..with 4.10s 4000 rpms was 110mph,,,and 5000 rpms was 138 mph..but can only go that for short period,,i did just that with 4.10s after about 5 min at 140 the rear end fluid was spraying out my vent all over the back of my car ,,it smelled really bad,,,made me sick,,,i like the 3.73 better ,,,maybe SOHC motors need more gear???

 

4.10's at 70 mph on the interstate will put you at 2400 rpms, thats a small price to pay to accelerate like a raped ape compared to your stock gears.

 

my 3.73s are ,,at 75mph is 2650 rpms,,i got the speed cal too..i love top end...i havent when over 110 yet with 3.73s sometimes you got no room...[&o]