Rear disc swap, front Ranger swap, stopping not that fabulous

[MickeySpiers]

The brakes in my '91 4 door have been unimpressive for longer than I can remember. 7 or 8 years ago I swapped in a '99 Explorer rear with discs, but noticed no difference in braking (I didn't do the MC or the adjustment of the rod, which at the time was all the rage). I just completed another brake job tho that I thought would fix this; I replaced close to every aspect of the brakes - replaced the rotors, parking brake shoes, calipers, hardware and pads in the rear, and now the front end sports the dual piston calipers and rotors from a '96 Ranger (everything new but the caliper mounts and the knuckles). New Master Cylinder that was supposed to go in a '95 Explorer. I've bled the brakes, and then had them bled at a shop to be sure. Pedal is firm, if anything too firm, brake pedal takes muscle to get it anywhere near the floor, which is the way it's been. Brake tests are still unremarkable, I don't think the new Ranger brakes or the master cylinder changed a thing in the way the truck stops. I'm running 32's, which are larger than stock but far smaller than most on this board. The power booster is the same one that was in it 22 years ago when I drove it off the showroom floor, and is the only thing I've not touched that I can think of, and the vaccuum hose to it is in good shape.

Thoughts?

 

[Turdle]

When you bled the rear did it seem like enough fluid ran out? I wonder if the 95 master cylinder has excessive pressure going to the rear?

 

[MickeySpiers]

The rear trickled fluid about the same as the front. Had the missus in the drivers seat doing brake pedal duty, and noticed no difference in volume or force in any of the calipers...

 

[Turdle]

This thread might help you

http://www.explorerforum.com/forums/showthread.php?t=141366&highlight=proportion+valve

 

[MickeySpiers]

I've read a lot of threads on here about the disc swap, but I've not seen that one. Good info in that Jon, but I don't believe my issue is proportioning - neither the fronts or the rears on mine seem to be getting enough pressure, if I was to guess. None of my tires lock up under heavy braking, ever, unless there is ice involved, that doesn't seem right...

 

[Combat_Medic]

Share results...

I have a 1997 explorer 8.8 l/s disc rear and 1995 ford ranger d35 ttb with 3.73 gears to replace the 3.27 gears and rear drums in my 1993 mazda navajo. Any resolution to your problems or other advice would be welcome information!

 

[MickeySpiers]

I have a 1997 explorer 8.8 l/s disc rear and 1995 ford ranger d35 ttb with 3.73 gears to replace the 3.27 gears and rear drums in my 1993 mazda navajo. Any resolution to your problems or other advice would be welcome information!

I presume you've read all of the posts about how to do these installs so I won't bore you with that, but I will stress the importance of getting new bolts to attach the caliper mounts to the front knuckles. These are about five bucks at Advance, buy them and pitch what came from the junkyard no matter how good they look. Then use LockTite on the new bolts, and torque them to the high end of what the Haynes lists as spec. Those bolts are prone to work loose pretty easy and losing front brakes is bad. With your '93 you won't have the E-brake nightmare that occurs in the '92 and earlier model so some small U-clamp jobs from the hardware store and you're good there. If you're handy or creative with a tubing bender you'll be in good shape with the rear brakes. Last thing, since your "new" rear axle is sitting around at the moment, replace all the wheel seals & bearings now before they're in the truck with brakes in the way and not so fun to get at...

 

[jd4242]

What was the part number of the mc you used? Do you still have abs? When I did my swap WITH the proper mc it was night and day.I bypassed my rabs in the frame rail tho, I can lock up all four of my tires (36x14.50) truck stops better than my car!

The 95 mc should be one with NO proportioning valve, NO cruise, NO abs..nothing just the basic 95mc and do not touch the rod in the booster.

 

[MickeySpiers]

What was the part number of the mc you used?

I bought this from Advance Auto:

Cardone Select New Master Cylinder

Part No. 13-2696

Product Application(s):
1995 Ford Explorer
•New; w/Cruise Control and w/o Proportioning Valves on Master Cylinder; Supplied w/Reservoir

Also happens to fit the '96 Ranger that I got the front calipers from, so it meshed nicely. I realize this one has that front port for 4WABS, and I bought it that way since for some reason I still hope to graft ABS into this at some point. For now, that front MC port is plugged, and yes I still have the RABS intact, haven't modified it at all.

Every other vehicle I currently or have owned, the ABS kicks the pedal back when it's active, but I don't get that in this. It just doens't stop as well as i think it should.

 

[jd4242]

Maybe your rabs/proportion valve is bad.they go bad all the time.thats why I bypassed mine.I had no rear breaks, bleed normal, pedal felt good but just no pressure was going to the rear.

 

[dkchrist]

Did you seat the pads and be sure to clean the oil and rust preventative off the rotors (if new)?

Long shot but this would make the brakes feel ok but not stop for poo.

 

[Xeek]

The 95 mc should be one with NO proportioning valve, NO cruise, NO abs

I bought this from Advance Auto:

Cardone Select New Master Cylinder

Part No. 13-2696

Product Application(s):
1995 Ford Explorer
•New; w/Cruise Control and w/o Proportioning Valves on Master Cylinder; Supplied w/Reservoir

theres an issue....

ive done this on my exploder and ranger. 99 axle with the proper 95 mc. dont have any problems. brakes feel really good on both trucks

 

[MickeySpiers]

Maybe your rabs/proportion valve is bad.they go bad all the time.thats why I bypassed mine.I had no rear breaks, bleed normal, pedal felt good but just no pressure was going to the rear.

That thing is the framerail somewhere, I'll try to find it this weekend & bypass it. Can't hurt, at this point...

 

[MickeySpiers]

Did you seat the pads and be sure to clean the oil and rust preventative off the rotors (if new)?

Long shot but this would make the brakes feel ok but not stop for poo.

Yep and yep. Brake cleaner on the rotors should have cleared that gunk up. All the components (pads, rotors, hardware) I used were new, just the hangers and such were boneyard pieces.

I know it's not much of a comparison, but the brake pedal is very stiff, compared to the sponge that is in my '98 2500 Suburban, and the pedal in the wife's '08 Taurus, which actually stops the car when you use it.

 

[MickeySpiers]

theres an issue....

ive done this on my exploder and ranger. 99 axle with the proper 95 mc. dont have any problems. brakes feel really good on both trucks

Agreed, something is amiss. What is irritating is that it's not a new problem, the brakes were unimpressive before I did the MC and the front Ranger brakes, I was just expecting it to be better when I finished. I'm really starting to wonder if it's the booster.

The cruise control thing - the difference is the front ABS port. Vehicles listed with no cruise didn't have the front ABS port on the MC, and those with cruise have the front ABS port. I just plugged that front port as I hope to put 4 wheel ABS in at some point (the missus sometimes drives this in winter, and I'd rather have 4 wheel ABS in the ice & snow).

 

[dkchrist]

You say extremely stiff pedal? That almost sounds like you have a booster problem (as you mentioned). Does the pedal change when you shut the truck off? Does it tend to get stiff after you use up the vacuum in the booster? If it stays the same or doesn't change much you either have a bad booster or poor vacuum to the booster.

 

[MickeySpiers]

Always a fun reminder of how poor the brakes are after a long time of driving a rental car that actually stops when you use the brake pedal...

You say extremely stiff pedal? That almost sounds like you have a booster problem (as you mentioned). Does the pedal change when you shut the truck off? Does it tend to get stiff after you use up the vacuum in the booster? If it stays the same or doesn't change much you either have a bad booster or poor vacuum to the booster.

The pedal does change, it gets more a little more stiff, when I kill the motor. Nothing drastic. I haven't been able to change the feel of the pedal by pumping the brakes, so I guess the answer is that I am unable to use up whatever vaccuum is available from the booster. The most dominant "feature" of the brakes is that they work and feel fine in average driving, but if I dynamite the brake pedal, it initially fights back, then eases down to where the brakes engage and bite; about a half-second passes between stomping the pedal, and the brakes getting around to trying to lock the wheels up. But in normal braking the response is immediate, tho even gently shoving the pedal to the floor won't get the truck to stop really quickly.

I developed a horrible vibation when under load from the engine, turns out 250,000 miles is about all that driveshaft was good for so since I was underneith last night putting in a new one, I gave all the brakes a good look-see. No leaks, nothing loose, everything still looks new. Booster is really all that's left, assuming the replacement parts were all good, so I guess I'll have to go down that route. I haven't checked the manual yet to see if there's a way to test the vaccuum supply to the booster. The hose is fine, no cracks, but I haven't pulled it off yet to see how much/little vaccuum there is in there.

 

[rickybobby]

The change should be drastic after 3-4 pumps. It really sounds like you have a bad booster.