How can I tell if my 1996 F-250 4X2 PSD has a locking rear differential? I have done the burn out test on slick roads and in gravel. If it does have a locking rear diffential, it no longer works.

How do I deciffer the rear axle codes on the sticker inside the drivers side door. What code signifies a limited slip diff. and what code tells whether you have a locking diff.

The reason I seem so perplexed about this, is because there are a whole series of wire, attached to a sensor on top of the rear differential. I would assume this is the computer control for the locking mechanisim, and that I have a locking rear diff.

 

That wire on top of your diff is for the ABS, has nothing to do with differential action.

Look at the axle code on your door jamb sticker, if it starts w/H, ie "H5" it was a limited slip from the factory. Please note that a limited slip is not a locker. The Trac-Loks that Ford used as limited slips didn't even work when new, so either way you've got an open rear end IMO.

 

Thanks for the info.:-)

So what code(s) does Ford use for a locking rear diff?

 

The wires and such on top of the diff is the ABS SPEED SENSOR. If you unplugged it, you're speedo wouldn't work. The ford traction lok is a good limited slip, there are ways to make it more aggressive, but it is a good unit stock. There are no lockers on any stock vehicles except a few of the NEW vehicles from other companies. Look at the tag on the rear cover of the diff, it will say what your gear ratio is, for example, 3 55 or 3 08 (the space signifies an open differential). Or 3L55 or 3L08 for a limited slip. My (now gone) old 95 F-150 has a limited slip, and my new truck is an open diff, HUGE difference, so YES THEY DO WORK, and they work VERY well. Not sure where he's getting that information from, but I have personal experience. The LS uses 3 fiber disks on each side of the clutch pack, you can install 4 fiber disks and get a much more aggresive LS, but the 3 fiber disks is good for a daily driven truck.


Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Flowmaster Exhaust, Sunroof, Clear corners w/ Diamond headlights, CD player with 2 10" subs and some 32" BFG Muds .

Thats it for now, saving for a stang. Check out my Gallery for a look-see.


Justin

 

I get my information from watching trucks on the trail, even new ones. Mustang, dont' suppose you have access to a digital video camera?

 

ill agree the f150 rear diff works well when it works
ive got the 373 limited slip and it does work good
untill you abuse it
mine is new now for the fourth time
seems pulling my 24 foot fifth wheel is kinda hard on the diff
now that the trailor is sold and i havnt put my 36 inch swampers on it yet the rear end is still working good
guess ill just have to keep my foot out of it

 

It looks like someone sprayed the underside of my truck with some sort of black primer. My rear diffential and axle were completely repainted, so I can not find any sort of tag on it with the differential info. What does the tag look like, and where is it on the diff.? Is it something that can peal off?

 

I do have a digital camera. I speak of my experience, if you beat the truck off road the LS doesn't work AS well because it's not as aggresive as a locker, but it makes a big difference over an open diff, i've done light off roading with both. It's a great unit for everyday driving, off roading i'd pass on it to something more aggressive. Mine had 110k miles on it and it worked fine until my truck was totalled. I just bought a traction Lok for my new truck, $50 bucks.

The tag is a small metal one that is attached to the rear end cover. The tag is held by the bolts holding the cover on. It's not something that could be peeled off. The number on your doorjam will work too but I'm not sure what number equals what.


Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Flowmaster Exhaust, Sunroof, Clear corners w/ Diamond headlights, CD player with 2 10" subs and some 32" BFG Muds .

Thats it for now, saving for a stang. Check out my Gallery for a look-see.


Justin

 

An easier way to tell if you have a limited slip or not, is to put two stands under the rear end so the tires are off the ground. Block the tires and put the tranny in neutral. Turn one of the tires, if the other tire spins in the same direction, it's a limited slip. If it turns in the opposite direction, it's an open. The real way to do a "burn out" test is to put 1 tire on a really slippery surface and the other on pavement. Floor it and if you don't go anywhere quickly, as in the tire with the least traction just sits there and spins and the other tire get's little or no power, than you have an open or you're LS is shot.


Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Flowmaster Exhaust, Sunroof, Clear corners w/ Diamond headlights, CD player with 2 10" subs and some 32" BFG Muds .

Thats it for now, saving for a stang. Check out my Gallery for a look-see.


Justin

 

Does anyone know if a lightning rear end will fit in a regular 2wd F-150, and is the driveshaft the same length on an E4od as with a 4r70w

 

Yes, and probably not.

 

The stock Trac-Loc is heavily biased to street use where these truck see most use, the clutch packs are even stacked in a way that cannot possibly provide more than a minimum of added traction. This can be vastly improved by simply restacking the packs and shimming it a little tighter. Here's the reference for axle info.. Ford Axle Code Chart .: Articles

 

The breakaway torque test for the 8.8TL is pretty slim - it is possible to do the spin test to exceed the torque just by turning the wheel fast enuf. I had repacked my LS with better kevlar plates (which I dunno if they are even available anymore) cuz if you use certain brands of synthetic axle lube - with or without the modifier - the glue on the organic plates disolves.

The wire(s) to the diff are the RABS exciter ring. unplugging it will not affect the speedo - VSS signal is taken from the adaptor on the side of the tranny tailshaft(xfer case) These trucks had 2 mechanisms - an actual by god cable into the speedo, and a simple magnet for the VSS signal

 

You guys realize that Brad57 dug up a thread that's almost six years old, right?