31" tire gear selection

[zach805]

Hello everyone i had a question about tire size and gear selection and was wondering if anyone had any experience with this or could help me out

I wanna lift my 94 4x4 i was thinking just coil spacers or washers to lift it a little put some new shocks(it needs them) and throw some 31's on the stock rims. Heres the kicker i dont know if i can with my gears and regearing it is out of the option i think cause of money

So i decoded my axle thanks to this website and i have 3.27s riding on a 28.9" tire. It says on the axle ratio chart and calculate axle ratio thing that i need a 3.51 to maintain stock ratio which would mean i need a 3.55 stock gear set front and back (that being the closet i think they make to 3.51)

So this is what i was thinking it said that my high ratio would be a 3.19 so being that i have 3.27 thats a lower ratio then that so i think it could maybe happen

basically would it be stupid to throw 31's on my truck with 3.27 gears i realize its going to loose some power and gas milage but i have the 4.0 its high milage though being 140,000 and i dont want the motor or tranny working super hard to move those 31's if thats the case

thanks everyone in advanced sry for the long post

 

[RavoHimself]

my brother runs 31's with 3.73's and its still a little under geared but gets wicked good gas mileage because the rpms aren't as high when cruising. he also has the 4.0

i would go 3.73's

 

[Original_Ranger84]

If your going with 31's you might as well get an axle with 3.73's. I'm assuming your trucks a 2wd...? this way you'll have more power if you have the off road capabilities.

 

[--weezl--]

4.10's with 31's are too low, i have the 4L SOHC though, with 33's they are about perfect, maybe still a little low... i would say if i were going to buy gears for 31's with my truck, i would probably use 3.73's at most... 3.55's would be fairly good, probably for your motor, which is slightly under powered, compaired to the newer ones...

what motor are you running? i would probably say 3.73's would be a good choice though...

my honest opinion, if you can bear with having next to no power for a short period of time, something you might want to do is buy the tires, then judge how much more power you want back...

 

[Hahnsb2]

3.27s and 31s would be awful, they're already awful with 235-75-15s. 3.73 minimum for 31s, I prefer 4.10s.

 

[strvger]

have to say i'm liking my 4.56's with 31 inch tires. lots of towing power for sure and not too bad for gas mileage. i plan on going to 32 inch tires eventually and that should make them even better.
just my $.02.

oh... Welcome to TRS !!!!!!!

.

 

[daniel3507]

4.10 would be like stock performance with 31s. Im running 4.10s and love it. Good power and the mileage doesnt suck

 

[Surrey]

My old truck was 4.10 with 31s, and I loved it, But that was a 2.9l v6. Actually, offroad I felt like lower gears would have been advantageous - I had to ride the clutch too much on really rough spots in 4hi - but that was a mostly stock truck, so you had to take it slow.

Im putting the 4.10 axles under my new truck (another 2.9l) that currently has 3.73s, but gas economy is not a concern to me, its not my DD.

 

[--weezl--]

My old truck was 4.10 with 31s, and I loved it, But that was a 2.9l v6. Actually, offroad I felt like lower gears would have been advantageous - I had to ride the clutch too much on really rough spots in 4hi - but that was a mostly stock truck, so you had to take it slow.

Im putting the 4.10 axles under my new truck (another 2.9l) that currently has 3.73s, but gas economy is not a concern to me, its not my DD.

if you're riding the clutch too much in 4h when off road, you should have been in 4L...

 

[Surrey]

if you're riding the clutch too much in 4h when off road, you should have been in 4L...

Nope. Just stuck behind friends with autos that drive too slow.

 

[--weezl--]

then you should have been in 4L...

when i wheel, i'm 90% of the time, in 4L, unless i'm on a logging road, or something similar... i am USUALLY in 2nd or 3rd gear, in 4L

 

[Surrey]

I prefer to save 4l for when I need it.
This wasn't hardcore wheeling or anything Im talking about, stock bronco II, stock Toyota 4runners, and a Pathfinder with 3" bodylift where the sort of things we were wheeling...

Had I not had people infront of me, 4hi would have been perfectly fine, and was on the many occasions I was in front.

edit - in fact I used 2nd and even 3rd gear when leading... It was like a gravel/dirt trail with random mud pits and washouts you had to slow down for.

 

[4x4junkie]

I have 4.10s and 33s on my 4.0L Ranger. It's OK, but not great. With 31s, 4.10s would be right about ideal.

From 3.27s it's very much worth the swap to at minimum 3.73s. Swapping the axles whole with salvage yard units is generally cheapest and least hassle.

 

[--weezl--]

issue with swapping just gears, or swapping the whole diff, and changing the pinion, is the contact pattern, i don't know much about it, but you have to check the backlash? (i think that's the right term) to make sure the pinion and ring gear are hitting properly, and not slightly out of alignment, from the factory, they check it, so the whole axle will be in line already...

 

[MountainMike]

3.27s and 31s would be awful, they're already awful with 235-75-15s. 3.73 minimum for 31s, I prefer 4.10s.

Hahns, I have 3.27s and 32s

Needless to say I have a set of 3.73s in the garage!