Limited slip

[mulishiaranger]

I was wondering what people verdict was on the LS axle in the FX4 ranger axle. I really want to get LS in my truck, and i'm trying to debate either buying the LS diff, or swapping in a LS ranger axle. And if i go the route of buying new or used diff, what would be my best bet? Any info would be great!

 

[Hahnsb2]

I really don't think LS's are worth a damn off-road, including the Torsen FX4 level II LSD I've seen in action, it seems to work pretty well on the street though. If you want an LS it's easiest to just swap axles.

 

[Fx4wannabe01]

^^And cheapest too.

Take your $250 LS, add the $100 install, and you've got a price tag that'll get you two junkyard axles.

If you get an FX4 31spline axle with the torsen, be aware that the early '02's were recalled when equipped with manual transmission, though there have been reports of grenading the torsen in automatic trucks. Get 03 and newer if you want to play it safe.

 

[JohnnyO]

Just be aware that on 2003-up Rangers, the FX4 has a regular Ford limited-slip and only the FX4 Level II has the good Torsen unit.

 

[mulishiaranger]

okay wicked, the junkyard here is such a rip off though, it sucks! although they did give me some pigtails for free yesterday ha. If i go for a diff, what would be the best bet on LS in you guy's opinion?

 

[Sprag-O]

I wheel with a re-packed trac-loc, and have never had any issues offroad (Other then blowing up the spiders)

I think you would be better off getting an easy to install lunchbox. Then you don't have the setup fees or anything, you're just replacing your spiders.

 

[MikeInIdaho]

...and you'll actually have a bona-fide locker, not a limited slip that might leave you stuck when you need it the most.

The problem with most factory LS units are their relatively low torque bias ratios, which means that they basically turn into open carriers once a little bit of throttle is applied in low-traction situations. Of course, throttling out of a low-traction situation is when you need a traction aid the most.

To be fair, it is possible to increase the torque bias ratio of the Trac-lok (and other clutch-driven LSD units) by "stuffing" more clutch discs into the unit and/or modifying the sequence of clutch discs and driven plates. Many aftermarket limited slips, such as the Detroit Truetrac, come standard with ratios as high as 5:1 and beyond. Nevertheless, an LSD will never outperform a locker (lunchbox or otherwise) offroad, regardless of how high its torque-bias ratio might be.

This has all been a long way of saying that I agree with the previous poster; spending a couple hundred bucks on a good lunchbox that can be installed in your driveway with a few simple hand tools would be much cheaper and better performing than an LSD. Sorry for the rant, good luck with whatever you choose