4:10 or 3:55's ????????

gasman1 · Jan 27, 2009

Right now i am running 3:55s in my jeep and have the opportunity to go to 4:10s for a low cost. A friend of mine advised me to stay with my current gears with the auto tyranny.

Info on my Jeep.
93 YJ, 4.0 with automatic tyranny, 3:55 gear ratio, Aussie Locker front (Dana 30) and back (Dana 35) on 33s. Street legal and i like it that way. I am not a hardcore wheeler, but i want to make it through the trails, at least most of them.
I know the first thing I will hear is get rid of the Dana 35, and i know this, but funds prevent me at this time.

What would you do?

Fordzuki · Jan 27, 2009

Does the jeep feel to you like it needs deeper gears?

MT4Runner · Jan 27, 2009

Yeah, what Fordzuki said...

...but two of my friends had TJ's with stock gears (3.55's or 3.73's??); one a '00 TJ with a 5-speed, the other a TJ Rubicon with an auto. They both went to 4.88's (which calc's a bit deep) while still running 33's and really liked that ratio. They both later went to 36 Iroks....and interestingly...now one is on 35" KM2's and the other is on sticky Krawlers for KOH, and still running the 4.88's.

If it's your daily driver, gear it for how you'll spend most of your time--4.10's sound like a reasonable ratio, especially if you're on 33's.

If it's only a semi daily-driver, but a street-legal trail rig, consider 4.56's or 4.88's.

Boonie Buster · Jan 27, 2009

I would go with the 4.10s personally, you'll accelerate faster, less stress on the tranny overall, and honestly right now how fast do you go on the highway? Say you go 70mph on a regular basis, what rpm are you at at that speed? add maybe 500-1000rpms (it'll be between there) and see what youre projected rpm would be at that speed. :awesomework:

Go with the 4.10s and don't look back ESCPECIALLY if it's on the cheap! I'm guessing you had like 205/75r15s on the jeep before with the same gearing, adding 33's won't FEEL like a lot especially with an auto tranny, compared to a 5 speed, (unless you own a 67hp toyota 4cyl. :fawkdancesmiley::haha

KarlVP · Jan 27, 2009

Four Tens will make you happy. Especially off road.

Dude · Jan 27, 2009

if you do the math, 4.18 would put you back to stock like gearing, so yes 4.10's with 33's would be ideal, it the closest you can get.

dventoza · Jan 27, 2009

i have 4.10s in my 97 tj with a 5 speed, 4.0, and dana 30/35 and i love it. i can go 70-75 on the freeway at around 2500rmp. and the acceleration is good. and good off road too.

Not Jobless · Jan 27, 2009

Do the 4.10's.

You can always pick up a used set of 35's if you think they're to low.

jakes89f150 · Jan 27, 2009

Jackazz said:
Do the 4.10's.

You can always pick up a used set of 35's if you think they're to low.

that D30 would commit suicide if you asked it to turn 35's

Do the 4.10's, im still kicking my self for not regearing when i had the chance

gasman1 · Jan 27, 2009

Thanks guys, at 60mph i am at about 2800 rpm's (i think) i do drive the freeway and it feels a bit high in the rpm's.

Not a daily driver, but drive it more in the summer back and forth to work.

I have no plans on going bigger than 33's but we all know how things change.

Pete

Boonie Buster · Jan 27, 2009

jakes89f150 said:
that D30 would commit suicide if you asked it to turn 35's

Do the 4.10's, im still kicking my self for not regearing when i had the chance

My dana 30 had 4.56s and 36s, only broke one shaft... granted i don't wheel, but still!:fawkdancesmiley::haha:

He'll be fine with 4.10s! :awesomework:

EDIT: That seems high for 33's at 60mph with an auto, you sure you're not in second gear?!?! :redneck::haha: Maybe double check tomorrow for sure. That seems high....:eeek:

Not Jobless · Jan 27, 2009

jakes89f150 said:
that D30 would commit suicide if you asked it to turn 35's

Trail spares should be carried but it'll be just fine.

KarlVP · Jan 27, 2009

Jackazz said:
Trail spares should be carried but it'll be just fine.

Quoted for all time.

This man speaks only the truth. D30 Open for mild wheeling with 35's will hold up just fine. Locked is pushing it, but carry spare shafts and you will be great.

TreeClimber · Jan 28, 2009

I've got a set of 4.10s for a TJ, complete axles, for sale if anyone is interested.

jakes89f150 · Jan 28, 2009

KarlVP said:
Quoted for all time.

This man speaks only the truth. D30 Open for mild wheeling with 35's will hold up just fine. Locked is pushing it, but carry spare shafts and you will be great.

he has an aussie in the front, and yes 2800rpm does seem high.

Dude · Jan 28, 2009

93 YJ, 4.0 with automatic = 3 speed auto, no overdrive.

Murkman · Jan 28, 2009

Who's the one here who thinks that RPM's will lower with 4.10's. Ain't going to happen.

Anyway I have a '93 Yj with a 4.0 liter 33" tires and 4.10's. Often wish it was 4.56 or 4.88 but it works well onroad and offroad who cares it's got Terra 4 to 1 in the x-fer.

zukkev · Jan 28, 2009

Hey Pete,
I'd go with the 4:10's, especially if they're on the cheap....I have yet to wheel with ya, but seems to me you are the somewhat cautious type, as I am (to a point!

); 2800 rpms does seem abit high with your current setup---my question is, is this rpm at what the speedo says, or actual speed, cuz your speedo should be way off right now! (Are you passing everyone???)....bottom line is go for it, you'll be happy all around.:awesomework:

Dude · Jan 28, 2009

Murkman said:
Who's the one here who thinks that RPM's will lower with 4.10's.

ummm, nobody?

TigTorch · Jan 28, 2009

4.10 ratio is a better match for your 33" tire size. You will not be geared too low, even with the auto.

Hate to say this but.....If your gonna' install gears go to 4.88's. You will soon want 35" tires. 33" to 35" is a huge jump in capability on the trails.