rear axle and brake work

[hasoan]

Hi. I am starting to plan a rear axle project on my 96 xlt and was wondering if anyone had some suggestions. Here is what I need and want to do:

Problems:
- right rear caliper has slow leak.
- both rear parking brakes seem frozen(will not engage)
- differential housing seal is leaking (presumably because I used it to jack the rear)

Tentative plan:
- drain diff and replace both parking brake assemblies
- replace both calipers (I think using 2 different ones might not be wise) and pads.
- refill diff with red line shockproof gear oil. I have 5 qts of lightweight and 1 qt of heavy sitting around. I figure I'll put the 1 qt heavy plus remainder lw in the rear. If I get around to the front diff I'll use the rest of the lw for that.

Does anyone have suggestions on how I should alter this plan?
Thanks!

 

[crunchie_frog]

I am guessing your rotors and axle bearings are okay. If the parking brakes are frozen, the inside of the rotors where the parking shoes engage are probably a mess. If your really cheap like me, you may want to consider rebuild of the calipers it may save you $15 or so. I will say if you are up north, while you are back there, take a look at the brake line, particularly the one that goes to both sides and goes over the differential. I have a vehicle from up north where this rusted to the point of leaking and I have read on here where others have had it rust out and leak as well. Not a fun feeling if this happens when you are driving.

 

[bobflood]

Replacing the parking brakes is MUCH easier with the axles pulled out - which is in turn easier since you will already have the differential open. You might want to consider also replacing rear bearings and axle seals while you have this all apart. My limited slip diff took 90W145 with friction modifier - about 2.5 qts total. One hint - make SURE you can get the diff fill plug open BEFORE you pull off diff cover and drain. Not good to get all this done - then find that you can't refill diff.

 

[white_shadow]

Replacing the parking brakes is MUCH easier with the axles pulled out - which is in turn easier since you will already have the differential open. You might want to consider also replacing rear bearings and axle seals while you have this all apart. My limited slip diff took 90W145 with friction modifier - about 2.5 qts total. One hint - make SURE you can get the diff fill plug open BEFORE you pull off diff cover and drain. Not good to get all this done - then find that you can't refill diff.

ford says the rear diff takes 75w140 with the modifier.

 

[hasoan]

I should probably mention that I don't have another car to use while I do this, so that will affect my plans a bit.

I am guessing your rotors and axle bearings are okay. If the parking brakes are frozen, the inside of the rotors where the parking shoes engage are probably a mess. If your really cheap like me, you may want to consider rebuild of the calipers it may save you $15 or so. I will say if you are up north, while you are back there, take a look at the brake line, particularly the one that goes to both sides and goes over the differential. I have a vehicle from up north where this rusted to the point of leaking and I have read on here where others have had it rust out and leak as well. Not a fun feeling if this happens when you are driving.

Well, I've never rebuilt a caliper, and I probably could figure it out but I don't want to make things more complicated if i don't have to. Also I might replace the rotors depending on the condition... IDK they're just rear brakes and I really just need to stop the leak and fix the parking brake. As for the brake lines, I just replaced the rear axle and front to rear lines a few months ago. (That's when I think I broke the seal on the diff.) It occured to me then that I had no "emergency" brake to use either! As you can probably guess, this car has a LOT of rust!

Replacing the parking brakes is MUCH easier with the axles pulled out - which is in turn easier since you will already have the differential open. You might want to consider also replacing rear bearings and axle seals while you have this all apart. My limited slip diff took 90W145 with friction modifier - about 2.5 qts total. One hint - make SURE you can get the diff fill plug open BEFORE you pull off diff cover and drain. Not good to get all this done - then find that you can't refill diff.

I hear you about the fill plug. Looking at it there's a lot of rust. I will have to see if i can loosen it up with pb blaster or something and hopefully use my impact wrench if i can get it up there. Although a breaker bar might be better. If that fails maybe i can drive to a shop and ask them just to loosen the plug

Rear bearings and axle seals: hmm, i hadn't thought of that. I'll check the prices and see if that is going to hurt me a lot. I believe i saw full parking brake assemblies (or maybe full rear brake kits) for sale somewhere, but I dont remember what all was included at the moment. I probably have a few options on how to buy the parts. I just know that in the past on other cars I have ended up replacing a lot more than i originally had planned, so I might go on the side of caution with this rusty mess.

As for the oil type, the redline lightweight oil says: "Film thickness greater than an SAE 75W140, yet low fluid friction like 80W gear oil or 30W motor oil" and the heavy: "Film thickness greater than an SAE 75W250, yet low fluid friction like 75W90" It also seems that the already have friction modifiers so I probably don't need it. I'm not afraid to experiment a little, and I don't think that I can mess up too much here, except that the LS might not work as well. I can add some modifier later if it's a problem. But I'm guessing the diff oil has never been changed in 120k miles. (I'm at least the third owner)

Thanks for all the advice guys!

 

[bobflood]

ford says the rear diff takes 75w140 with the modifier.

+1 on this. Poor memory plus lousy typing are not a good combination when trying to impart accurate information!! Sorry about diff oil weight mistake!!

Rear bearings and seals are relatively inexpensive; you will probably need a slide hammer to pull the old bearings (usually available for loan at auto parts stores).

 

[drdoom]

If you get loaners at Advance, ask for kit #46. It is a master puller set, and I suggest using the tap screw (like for dent pulling) for pulling the seals...just drill three pilot holes around the seal, in the metal part of course, and use the tapping screw + slide hammer. Very clean & easy seal pulling. Then you can use the bearing puller to finish the job.

Deposit for kit #46 is about $160USD.