Help prepping my donor rear end.

[Usudno]

So I got my rear end today. Rotors are trash but I planned on replacing them. My question is what all do I need to keep from it? I know the axels, housing, calipers, gears, and rotors. Just want to make sure when I'm tearing it down for sanding/painting that I'm not tossing anything important.

[Jeff Kleiner]

As I recall from earlier posts you do not intend to change gears or switch to a Fox width configuration. You can lose the heavy "dog bone" weight on the nose below the pinion flange. If you are going with a 3 link the quad shock brackets can be cut off of the housing to clean it up. I know I have mentioned to you that swapping calipers to the forward side of the axle results in a simpler and neater parking brake cable routing as well as eliminating the possibility of coilover interference---now would be the time to do so if you're so inclined.

Cheers,
Jeff

[AC Bill]

Keep the vent cap somewhere safe, if you remove it. You could also just mask it off as I did. Jeff mentions cutting off the upper quad shock bushing eyes, but you might want to keep the right one, if you decide to add an optional banana bracket support brace. You can buy a commericaly made one or even make your own brace.

This thread might help you grasp what i am talking about.
http://www.ffcars.com/forums/17-factory-five-roadsters/5168-vpm-s-banana-bracket-3-link-bracket-support-brace-kits-how-i-did.html

[Jeff Kleiner]

...Jeff mentions cutting off the upper quad shock bushing eyes, but you might want to keep the right one, if you decide to add an optional banana bracket support brace...

Bill,
I was talking about the quad shock mounts welded to the axle tubes---you are referring to the upper control arm mounts which are cast into the center section. FYI, I remove the original bushings from them and silicone the appropriate sized tapered rubber stopper in the hole. I then drill a hole in the center to route the parking brake cables through. When the calipers are relocated to the front nothing further is required to secure the cables:

http://i269.photobucket.com/albums/jj43/jkleiner/Mk4%207276/100_1874.jpg

Jeff

[AC Bill]

Jeff your right, I was thinking of the upper control arm mounting eyes. I guess that's another good way to make use of them..:)

[Usudno]

I posted these same pictures in my build thread but I figured it would get a little more traction on this board. I have a few questions regarding my rear end prep. There are a few brackets that I am unsure of and my next step is to pull the cover, blast it, spray it with alumablast, pull the axles, and get it painted up. I could use some advice on these few.

61313
1. This guy here which I am assuming is a caliper location bracket. Do i need to keep this around? Should i blast it and paint it?

61314
2. This guy here which I know attached to the brake line previously and to the caliper with a banjo bolt. Should i be keeping this as well? Any ideas on cleanup?

61315
3. I'm sure this is a vent but I am not sure what goes here. I have been plugging it with random objects to keep rust remover and gunk out.

61316

And lastly, A coat of Rustoleum Rust reformer.


I'm just about done with it. Hopefully tomorrow afternoon i can get it cleaned up more. I'll get the cover off and drain it. Probably pull the axles and blast the cover. I'm thinking of going alumablast on the cover and just a black on the rear end.


Thanks for the advice as always

Scott

[Jeff Kleiner]

Scott,
I replied in your build thread.

Jeff

[canuck1]

I'll give you a tip that may or may not be relevant.

You might want to clamp a couple straight pieces of angle on each of the axle/caliper mounting brackets(oriented so they extend out forward or back beyond the diff center). If you measure between the ends of the pieces you've clamped on, you will get some idea if your axle housing and tubes are still all square to each other.

I didn't do it and my donor axle housing had probably been jammed into a curb at some point (not uncommon for many Mustangs over the years, we also discovered the axle on that side was slightly bent as well). It wasn't enough to be visible to the eye but as soon as my car went on an alignment machine, it was clear one axle tube was toed out. I went ahead and ran it like this for a while but soon realized it was causing an unpredictable rear-steer effect when I got off the throttle. I pulled the (3-link) axle, had it straightened in a large 'lathe' (?) by a machine shop and re-assembled. Much better. I try to give this tip when I can in the hopes others can avoid the effort and expense I went to in order to make it right. Much easier to find a new (straight) housing from the get go!

Sean

[Usudno]

Thanks for the tip canuck1. I will give it a shot

[frankb]

Usudno: After reading some of the horror stories about the mustang rear end axle tube issues, I decided to weld mine to the center section. This is probably overkill in most of our builds, but cheap insurance against tweaking the axle tubes, especially if you plan to race your Cobra. Any good weld shop in your area can do the work, but an axle shop might be a better choice because they have the experience.

61325

I also welded the banana bracket to the axle tube to strengthen the assembly. Then I had the whole thing powder coated prior to reassembly.

61326

[NAZ]

As frankb said above, it's a good idea to weld the axel tubes to the center section if you plan to race your car or if you put a high torque load on the rear end. But there are several ways I've seen this done and most are poor procedures. The center section is cast and the axel tubes are mild steel. Whether you take it to a shop or do it yourself, the proper way to weld these is to use a high nickel rod and TIG weld them SLOWLY and in a fixture that will prevent the axel from warping. A series of small beads welded diametrically opposed until you have a complete weld. I use an IR gun and ensure the heat affected area never gets above 450-degrees. I only preheat to bring the parts up to at least 70-degrees if it's cold in the shop. This is not cheap -- the correct process takes a lot of labor hours and the ni-rod is ~$100 a pound. But this process will give you a good quality result.
61333 61335 61336