Re-Gearing is this right

[mitch]

Ok i need to re-gear my front and rear axels. the front is the dana 35 ttb and the 8.8 rear. I have 32's right know but will be getting 33's in bit the stock gearing is 3.73. I found this page http://4wheeloffroad.com/techarticles/3194/
when searching on google to find the new gear size. After doing the formula it gives you, I got 4.10 for the new gear size. But looking on this site and others i saw people with 35s and higher running 4.10s. Have i done something wrong? I dont do any rockcrawing just trail riding, so i dont need the super low gears just ones to get it back close to stock. Can anyone tell me the right gear sizes to use
thanks mitch

 

[Maniak]

We have 4.10 gears and run 32" tires. This gives us the same effective ratio as someone with 235x75r15 tires and 3.73 gears. This worked great for our truck. We did have 31's for a while with teh 4.10 gears and that was too much gear for highway (I drive 95% highway when I take the truck to work).

We run an automatic tranny and in OD (a4ld) I belive 2500 rpms was 72mph..

We now have a 700r4 and 72 is 2200 rpms..

~Mark

 

[hiridin]

if yer moving up to 33's i think u'd be happiest with 4.56's. it'll be a little bit of an improvement over stock u'll be running like 200 rpms higher at 65mph in 4th gear than it is now but the tires are bigger and heavier so it takes a lil more to move them sooooo...... it kind of evens itself out. i'd go with 4.56's and ya i know im running 4.56's and 35's but truth is i should've gone with 4.88's. i think it should be 4.10's for 31's.... 4.56's for 33's.... and 4.88's for 35's. that way u atleast have some power to move those bigger tires.

 

[mitch]

thanks maniak and hiridin , I dont know very much about gears so which gears would be the for highway (give good gas mileage) and good enough for offroading. also what do the lower gears do for offroading ( i know this is a stupid question)

 

[hiridin]

these motors don't have a lot of power... gearing it correctly makes up for that. 4.10's might give better gas mileage but then again maybe not. if its straining to move it then it'll use more gas. with 4.56's it won't have to work as hard to move it but u'll be running a lil bit higher rpm's. either way gas mileage will suck. the whole lil bit better gas mileage thing is why i went with 4.56's instead of 4.88's i still get crappy gas mileage and i'm dissapointed with power. would be better to get crappy gas mileage but atleast be happy with it power wise. don't get me wrong its not horrible but it could be better

 

[Brandons]

I have stock gears at 3.27, im thinking of grabbing the axles from the other explorer that are 3.55. Would 31" tires be a good idea to compensate for the speedo so it is somewhat accurate?

 

[hiridin]

i wouldn't be worried about the speedometer. i'd be worried about 3.55's and 31's. thats what i had on mine at first and it was PATHETIC :thumbdwn: keep in mind i have a manual tranny. but damn it sucked. but to answer yer question ya it would probably get it pretty close

 

[IZwack]

umm for trail riding, if u have a 4x4, dont forget that u always have a transfer case to take advantage of if ur low on torque

 

[Brandons]

thanks hiridin, the reason i am thinking of changing the axles is since the eddie baur has had the ball joints recently done and it appears in pretty good condition up front. Of course the explorer is need new ball joints and tires, so its good timing.

 

[Creager]

two weeks ago i had 3.27 gears on 32"s

it sucked royally. I couldnt go wheeling if i tried.

Today, after two weeks of man handling the TrueTrac i bought from hiridin and overcomming the learning curve associated to doing gears i finally finished regearing to 4.56!!

come 6 hours from now when i get off of work and finish the little stuff and finally get to take it for a test drive, ill tell ya how it works out

this is what i expect... in math

when i put the 32s on, i went down 103% in power (32"/29"*) *stock

when i put the new gears in gained 139% in power. 4.56/3.27*

that a 36% power increase over stock

 

[IZwack]

and overcomming the learning curve associated to doing gears i finally finished regearing to 4.56!!

Perhaps you can share (a write up for example) on how to regear?

 

[mitch]

hopefully i can do that when i replace mine in a bit

 

[IZwack]

wait where's the rest?

 

[Creager]

Post moved: http://www.explorerforum.com/forums/showthread.php?t=144780

 

[IZwack]

wow fantastic!!!!! WOOO! thanks!!! we need to put a sticky on this one!

 

[Creager]

speaking of which, i just got done test driving my truck after my new gear install... incredible. i am glad i went with 4.56 then anything higher. 4.10's would have definatly not been enough.

Im kind of confused by speedometer though. Before i was reading 5mph lower then my actual speed. Now it seems like im going 5mph higher. Im getting tons more accelleration. i get to 70mph quicker then my truck has ever dreamed! thats why i think my speedo is way off haha

 

[unclemeat]

Where you realy notice the regear change is how fast the motor will wind up. You can check your actual speed witha buddy with a cell phone or if you have a GPS unit. I found that after I regeared 3.73 to 4.56 and 235x75s to 33s that my speedometer was off by approximately 5% (reading higher than actual speed). With a lifted truck I look at that as a safety factor to compensated for decreased handling. There is a tech article on this site on how to correct the speedometer. It is relatively simple for the Gen I X.

 

[Creager]

according to the artical on the 4x4central.com page, 3.73 gearing came with a 19 tooth speedogear stock. and going from 3.73 to 4.56 only required a 20 tooth speedogear

i havent had a chance to actually count the theeth on mine but im guessing with 3.27 gearing stock, that id have a 17 tooth speedogear? and if that were the case then the 20 tooth speedogear is what i need?

 

[mitch]

IZwack is right that is a great right up

 

[off-road97Xplor]

Just a quick question, I have a SOHC that I'm in the process of modding into a street machine like expo's,boomins,etc. I want alot of accelleration and good launches(Maybe a burnout )
Right now I have 3.55 in the rear. I want to go with 4.10's. Do you guys think this is too high? I know the new Rangers have 4.10s as a factory option.
I'm going to be running 18 inch wheels and dropped 3inches.

Otherwise amazing, all of my other of my questions were answered.
I call a sticky on this one.