I am upgrading my 56 Panel and have found a 96 Explorer limited slip "Control Trac" rearend. My question is how does Control Trac affect the rearend and can I install this rearend only using the limited slip?

 

Think I got my answer on the Explorer forum. The wires going into my differential are for ABS. Since I don't have ABS I just don't worry about them. Control Trac is computer controlled for all wheel drive and 2 wheel drive. It's controlled at the transfe case so nothing to worry about there.

For those that have done the swap. Did you put the axle on top or bottom of your leaf springs?

If on top, what kind of drop did you get and did it require a C notch of the frame?

 

Springs are over our install - 1993 Explorer axle, actually has limited slip components, not that it matters much with a 239 flathead providing power. Biggest thing on the axle positioning was repositioning spring perches.

We did lower the height by taking out some spring leafs - that worked for us on the M68.

 

dcavan001,
Is the axle normally on top of the springs on a 50? On 53-56s the axle is on the bottom.

 

Springs were over the axle on mine - actually two sets because of the 1 ton configuration. After and before shots here. Now you have me worried there was something changed on mine originally.

 

That before picture is how 53-56s are. Looks like you had "helper" springs too. Your after picture looks very clean.

 

Thanks. You can't believe how much 60+ year-old Alberta mud there was to clean out. By the time we were done that, well, it looks ok now.

The Merc M68 is a true 1-ton, and one of the things we obviously had to do was get rid of a bunch of those leafs. It was a pretty rough ride before.

 

BJ my axle is going above the springs as per the Explorer. I did measure how much drop to expect but don't have it to hand. I think it was 4.25" though. I expect to have to notch the frame but not got there yet. You will need to arrange some lower shock brackets too. I have the ones off the explorer and think using the left on the right and vice versa might work with some modification.

 

ControlTrac really isn't about ABS. It is Borg Warner's attempt at All Wheel Drive and uses a set of electrically controlled clutches in the rear axle to transfer power. The problem with it is that it will overheat easily and burn out the clutches particularly off road. So in later versions they added another wire and a thermocouple that would then separate the clutches when there was heat build up which then would mean that you never knew when it would quit working. Mercedes, Chevrolet, GMC and others all used this system. Jeep never did.

In the early 2000s Ford went to ControlTrac II which utilized a viscous coupling in place of the clutch pack. This works well as Jeep started utilizing viscous in 1976 with the old Quadratrac system. It is very reliable but does not work well on glare ice . . . which is the only condition where it doesn't outperform almost all other 4WD systems.

Then Ford had a better idea and went back to electronically controlled clutches.

I'm not sure what your system looks like. My 2001 Explorer SportTrac axle has a single sensor with 2 wires going to it. Inside there is a toothed timing wheel that the ABS sensor reads.

If you truly have a ControlTrac rear axle and not just an ABS axle I think that without electricity going to it it acts just like a standard rear axle. When it is up in the air turn one wheel and if the other wheel moves in the opposite direction you are OK. If it moves in the same direction then the clutches are compressed together. You may want to consider replacing that clutch pack with a Detroit Locker if possible.

Does your axle still have its ID tag on it?

Hopefully you just have two wires which is for ABS only (more wires for ControlTrac). Then more luck if like mine below you will have True-Trac limited slip.






Toothed wheel beside ring gear is for ABS

 

Pete,
Mine is like yours only not cleaned up like the first picture.
The 96 Explorer's VIN sticker shows the rear axle to be a D4 and the Differentail tag has 3L73 both indicating limited slip. The two wires and sensor are held in by one 14mm bolt. The sensor aligns with the toothed ring on the back of the ring gear.

 

Sensor



96 Explorer rear axle

 

OK. That is for ABS not ControlTrac. I just put my sensor back in the hole after cleanup. Also left the waterproof connector in place so water had no chance to get in. Left the wires connected to nothing.

Your axle looks to be in good shape. Mine, although a 2001 had seen lots of Michigan winters. I had to cut the drums off with a plasma cutter.

 

My truck has a DJM flip kit and C notch. Total drop was around 8". In fact, I added new longer shackles to raise it up a little for clearance.
Not sure what it has for gears. (No tag and haven't opened up.) May add a locker eventually.

Not a great picture that I had on my phone. This is fully extended down.

 

1997 Explorer Sport 8.8 differential. Flipped on top of the springs

 

MattK1,
Need to hook up with you and see your C Notch. I'm guessing you had to raise the bed floor.