I have a 2000 F150 XLT 4x2 v6 with a 3.31 gear ratio. My previous truck had a 3.55ls. I want to upgrade to at least the 3.55ls and would like to use aftermarket parts.

I recently talked to a mechanic who said that it would be cheaper to install a used complete rear end but with only 10000 miles on the truck I dont want used parts.

I dont haul anything now but i am wondering if i should opt for the 3.73ls (if possible) as I am thinking of increasing my tire/wheel size. What are some quality gear manufacturers? What gear ratio should I opt for? How much work is involved in installing the gears?

 

You could get a 3:55 gear set and a Powertrax unit. It's a unit that locks during straight driving, and unlocks for turns. They run a little over $400, plus the cost of gears and installation. Still probably MUCH cheaper than a whole rear axle assembly,,,,,98

http://www.powertrax.com

 

so powertrax is kind of like a limited slip, but better? im asking because i was thinking of adding a limited slip to my rearend, but if powertrax is streetable, then ill go for that. thanks!

 

The Powertrax guys do a better job of explaining it than I could, but yes, it's streetable. From what I've read on their site, they convert an open differential to a "posi" unit, also. Makes it a great option for us traction deprived guys I'm planning to do a 4:10, with one of their units next year. My truck ought to live up to its looks then,,,,98

 

See what they have to say about LS/posi style rear differentials on this page. I know it's a little sensationalistic(whew), but is partly true. I've heard of guys having trouble with the clutch packs wearing out(burning up?) I think I'm still going with Powertrax,,,,98

http://www.powertrax.com/traction.htm

 

Powertrax is a bunch of crap I had one installed for a week and it had 4:10 gears on it and was very noisey and some times would hang up on turns draging the outside tire save your money aftermarket LS would be much better.

 

Thanks for the replies...I will check out the site. The mechanic that I was talking to had planned to trade my rear end assembly for a used one with Limited slip gears.

What is involved in the replacement of the gears? Can I use any size rear end from 3.31 to 4.10? How much should I expect to pay for the install if I purchase the gears myself?

Wayne

 

I had 3:73 gears (not LS) installed by the dealer before I took delivery of my '01 SuperCrew. The total charge was $575 which included resetting the computer.

 

Uhhhh..... road_rage.
Which one of the Powertrax units did you get?? They have one that acts like an LS unit, and the other is a locker style. If you got the locker, no wonder it made noise and would drag a tire. They says it's only recommended
for extreme off road conditions, and recreational offroad vehicles. All lockers make noise and sometimes act like yours did,,,,,98

 

powertrax locker type didn't suggest off road only.

 

Says on the website:

Although smoother than other competitive locking differentials, the brute force characteristics of the Powertrax Lock-Right Locker limit general application in less tolerant and more mainstream applications. In some vehicles, you will hear a light clicking noise as the gears are overrunning themselves and allowing the wheels to differentiate in a turn. This is normal of most lockers on the market today. We recommend the Lock-Right for vehicles that are primarily driven in severe driving conditions or are used for recreational off-road. For vehicles that are driven daily or require more mainstream application, the Powertrax No-Slip Traction System offers a quieter and smoother performance. Please see the No-Slip Traction System page

Sorry about that, maybe you were mislead by their dealer?

 

When our 99, F-150's factory L/S fail's, It will get an Auburn "Pro-Series" carrier or an Eaton-Posi. As for new ring & pinions, I have had better luck with US Gear (I have built probably three thousand differentials in my career).