fx4 rear discs

[tac1015]

I want to change the rear drums on my 07 level 2 to discs, explorer rear ends have 31 spline like on my level 2, has anyone put explorer rear discs on a 31 spline ranger rear end? You would think Ford would use the same housing ends on both 31 spline rear ends, but is it just a bolt in or not?

 

[JoshT]

IIRC Explorer disks are pretty much bolt on for a LII axle, they do use the same housing end. Take the Explorer lines and hoses, and everything from the mount outboard and it should nearly bolt on. Might have to adapt hose mounts for the axle since the Ranger used hard lines to the wheel cylinders, do not attach the hard lines directly to the caliper. The biggest issue you will run into is parking brake cables, but since the 2010 & 2011 rangers had rear disks you may be able to look there for ideas on how to make them work right.

 

[gw33gp]

I realize it would be difficult to attach the hard lines to the caliper because of the different way it attaches but why do you say specifically not to attach the hard lines directly to the calipers? I upgraded my race car from drums in the rear to disc. I was able to attach the hard lines directly to the caliper. I have been running it that way for well over ten years and have not encountered any problems. Is there something I should be concerned about?

The only thing that comes to mind is it would be more difficult to change the pads with hard lines connected directly to the caliper. There are ways to overcome that as I did with my race car. Maybe that is not feasible with the Ranger. I know the front calipers need flex lines to the caliper because the caliper rotates back and forth with the steering knuckle but the rear doesn't do this.

 

[JoshT]

Their are two main styles of calipers. Fixed and Floating.

A fixed caliper does not move when brakes are applied. They have pistons on both sides of the rotor, and those pistons clamp down on the rotor while the caliper remains rigid. Since the body of the caliper does not move a hardline is fine with these. This is commonly found in the aftermarket 4+ piston brake kits.

With a floating caliper the caliper actually moves when brakes are applied. These have pistons on one side of the caliper. When a floating calipers actuates the pistons push the pad against the rotor, once the pad makes contact the body of caliper slides in the other direction so that the other pad makes contact and clamps down. Floating calipers require a flex line to allow for caliper movement. If the line can't flex something else is going to wear prematurely or fail. Whether it would be the caliper, the pads, or the rotor I couldn't say. These calipers are what most factory cars use.

All RBVs used floating calipers, Explorer rears included, as did the Mustang and most of Ford's other cars that I am aware of.

I don't know what style your race car uses. If it's a track only and depending on the style of racing I probably wouldn't worry about it too much. If they are on a road course or auto-x car and/or see a lot of street use then I'd be adding some flex lines ASAP if they are floating calipers.

 

[gw33gp]

My race car definitely has fixed calipers. I forgot about floating calipers. I have done brake jobs on many of those. That seems to be the OEM standard on non-performance, modern vehicles. Yes, they need a flex line going to them.

 

[JoshT]

If I had a race or performance car I'd probably go with fixed as well. The Mustang and Corvette both ran the PBR dual pistons that I'll be running on front so they should be good enough for my V8 Ranger. The Mustang rear disks probably would be as well, but the Explorers have a thicker, vented rotor and probably more suited to any truck duties it may see while still being fit for lite track usage should I ever get the chance. The Explorer brakes also have the benefit of already being mounted to the Explorer rear that was also installed.

 

[85_Ranger4x4]

I used a second PS soft brake line on the drivers side so I could keep the Ranger style brake line routing coming from the top of the differential rather than the DS brake caliper like an Explorer. Add mounts (I just welded a nut to each spring perch) and a little black spray paint and it looks OEM, I love it.

And I would get new soft brake lines, they don't last forever and can lock a wheel up when they go bad (I had a front one do that) They are easy to replace and not that expensive either.

 

[PlumCrazy]

I used a second PS soft brake line on the drivers side so I could keep the Ranger style brake line routing coming from the top of the differential rather than the DS brake caliper like an Explorer. Add mounts (I just welded a nut to each spring perch) and a little black spray paint and it looks OEM, I love it.

And I would get new soft brake lines, they don't last forever and can lock a wheel up when they go bad (I had a front one do that) They are easy to replace and not that expensive either.

^Same thing I did....works well.