So I pretty much no nothing about gears... I am putting the 39's on the truck soon and I hear I should regear to 4.88. I dont even really know what that means. How much we talking for parts and prob labor? Any info is great, thanks! O is that for back only or front to or what lol.

 

39's? I would go steeper than a 4.88... Don't fear the gear.

 

heres a good site for lesson 1
http://www.4lo.com/calc/geartable.htm

basically you change gears to get back rpms of the engine to match up better with the tires, that's why you will feel you have more power. good luck

 

Rear wheel drive, just the back. $800 to $1200 maybe......
4x4, front and back. Double the price.
And with 39" tires, you will really want it done.

 

So far thanks for the info, I think I get it. Sounds like something that costs $$ for 4x4.

 

means your driveshaft will turn 4.88 times for every rotation of the rear wheels

 

if there's anything shorter available like a 5.13 or so...that's what you want. Get the shortest you can find to turn those 39s.

 

Now time for a dumber question ... I've got a 2005 F150, I think I recall reading that there is an axle code on your door or somewhere that will tell which gears you have .. any truth to this/which codes indicate which gears? I think I have 3.55's but am not sure..

 

That's insane! I had my 4x4 done, parts and labor, front and back for just over $1000.

Shop around. Ebay is wonderful...

 

It doesn't really matter because there is no factory ratio that will make sense with 39s. Not 3.31...not 3.55...not 3.73.

Whatever is in there should come out anyways.

But yes, do a search there are several posts, some of them recent, about how to figure out your axle ratio.

 

That person probably isn't getting 39s. Different member.

 

Nope not just yet! Running the factory 265's and am just a little curious. I have a friend with an F150 which accelerates noticeably quicker and am considering regearing.

I'll try searching around and see what kind of dirt I can dig up

 

Hmm so I been checking around on gears and its a pain in the butt heh, i find the sites but not sure what im looking at. Anyone got link to the direct part for 4.88 gears? I know I will need these but not sure exaclty I need, just the gear or what. Do I have to get front or can I just get rear? Thanks

 

There are all sorts of brands out there to choose form. The gears that I chose for my rearend (the cheapest I could find) were $170. However, there were gearsets priced all the way up to $350. It's all about which brand you want. Also, we need to know if you have an 8.8" or 9.75" rearend. You'll also need to get install kits for both differentials. These include all new bearings, bearing races, shims, etc.. Master install kits (and make sure you get a master, not a minor or "mini") for the rear usually run around $75-$90. Install kits for the front are slightly more. The only other things you'll have to buy are new axle bearings and seals for the rear axle. The install kits usually do not come with these. Go to www.accuautoparts.com and click on axles/gears, select your vehicle, and choose which rearend you have. It will list all of the brands and gear ratios that they stock, as well as install kits, tools and other parts.

You must do both, unless you want to be buying a new tranfer case lol.

 

not sure what rear end i got, i know i got 3.73 but thats all i really know