So my 86 came stock with a 2.77 open, drum rear. I just picked up a 9 bolt 3.27 disk brake rear, which I am rebuilding with 4.11's.

So I am having some trouble understanding the rear disk setup. The first thing I thought was strange is that one caliper is mounted towards the front of the rotor, and the other caliper is mounted towards the back. Is this stock or did someone just mount a caliper backwards?

The second thing is the brake line. There is the the spot where the brake hose meets the rear in the middle, then the two lines branch off to each wheel. That part looks fine. On the drivers side the brake line then connected into a bracket, where a brake hose is connected going to the caliper. That looks normal to me.

But on the passenger side instead of having a bracket with a brake hose going to the caliper, the metal brake line was screwed directly onto the caliper through another one of those couplers, like the one in the center of the rear. No brake hose or bracket for a hose on the passenger side.

Both lines are rusted so I am going to replace them, but I'm not sure if the way the lines are set up now is factory, or of someone just rigged it up this way themselves. Any info would be great. If you have any photos of how everything is suppose to look, that would be VERY helpful.

 

You may want to call a differential shop on the rebuild aspect. I may be wrong, but I thought the 9 bolt Borg-Warners had a very limited selection of gears and that a 4.11 will not fit that carrier.

 

I read a few threads about people who are running 4.11's in a 9bolt. Plus 9bolt.com sells them so I should be alright. I didn't think they would fit either until I saw they were sold and people were running them.

 

Are your calipers fixed solid to the rearend, or are they floating on pins? If they are mounted solid, you have no issues. But if they float, you don't want a solid steel line connected at the caliper, that could eventually fatigue and crack the line. If the caliper can slide at all, you need a flexible hose from axle housing to caliper.

 

Im pretty sure there on pins. I read on another site that Gm did this so they wouldn't have 2 different part numbers for calipers, so they kept the same part and just flipped it on one wheel. I have to take another look at the calipers when I get home to see If there floating or not.