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Discussion Starter #1
I'm trying pull the rear end out of my 67 Lemans and I'm getting stuck at where and how to disconnect the brake hose that goes from the top of the differential to the frame. I'm guessing its something obvious because I'm not having any luck googling it and my assembly manual disappeared in my move. I'm super paranoid about brakes so I don't want to attack it blindly.

I think I'm seeing some kind of C-clip and nut on the frame side. Is it as simple as getting a wrench around it and backing it off?

What's the name for the assembly it connects to on the differential? Can it be disconnected from there or is it technically one piece?
 

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You are correct that is a "C" clip.
Take a wire brush to it and you will see it clearly.

FWIW; if your brakes are functioning and you wish to just remove the differential you can remove the wheels,
Then pull off the drums and unbolt the brake backing plates and suspend them out of the way.
Pull the axles. Also unbolt the upper center brake line distribution block/bracket from the upper diff/housing, Via that one bolt.
This allows the the whole assembly to be removed without touching the the brakes.
 

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The first pic you sent shows the brake hose which goes through the upper crossmember. The "C-clip" is indeed all that holds it in, BUT, you have to break loose the line that goes into the other side which, as I recall, is that "nut" you are seeing where the steel brake line goes into. Use a wrench on it to hold it in place and then turn out the fitting on the steel line. Then knock out the "C-clip" and pull the hose out.

My experience is that you may have trouble undoing that steel brake line from the rubber hose. Put a little penetrating oil, Liquid Wrench/PB Blaste etc., on the fitting and line and let it stand a while. Typically an open end wrench will round off the fitting. They make wrenches specific for steel lines which looks like a six-point box wrench with a cut into it to slip over the steel line called a Flare Nut Wrench - photo enclosed. These work better than an open box wrench.

However, if the fitting is really corroded, these too can round off the fitting. Next up is Vise-Grips. I typically clamp the Vice-Grips tight enough so as not to spin on the fitting nor tight enough to crush the fitting. Give it turn or work the fitting slightly left/right to break it loose. Vice-Grips will do the job for sure, but you may destroy the nut and I suspect at this point the line is corroded and frozen into the fitting and you are going to spin/twist the brake line off. If the line does twist off, then a new line will be in order unless you have the tools to splice in a section of steel brake line.

The fitting down at the bottom of the hose that attaches to the rear end is part of the hose - second photo. Looking at your picks, I would recommend replacing the rubber line and getting all new steel lines - while its out, I would rebuild the rear brakes if they have not already been done IF you are not replacing the rearend with something else.

I would not bother to undo the steel lines, just replace them with the rearend out with either pre-bent lines or do it yourself if you have the tools to do so.

Dropping the rear is pretty straight forward once you get the hose line undone. Once the rear is out, I would suggest installing new control arm bushings/bolts. If you wanted to go even further, and finances can be justified, I would add the boxed lower control arms and a rear sway bar for a little additional handling. Price out the new bushings and labor at a shop to install and it might be easier/cost effective to just go with new boxed lower control arms for now and then later install a rear sway bar.

:thumbsup:
 

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Discussion Starter #4
Thanks for the tips guys.

The rear end is coming out to get wire wheeled, painted, new bushings, and new tubular control arms. While it's out I'm also changing the diff fluid, grabbing all the gear numbers, and inspecting the axle bearings.

The brakes have been cleaned up and adjusted recently. They'll get a full rebuild and new lines when I have a front disk brake conversion done later this year. Depending on what happens when I take things apart I may go ahead and change the diff lines.

Does anyone know off the top of their head if the flare nuts are metric or SAE? I'm going to stop and get a set on my way home.
 

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Nuts should be SAE, metrics were not used "back then." Of course it does not mean that someone may have changed a few to metric over the years.


I also suggest the upper & lower control arm braces to tie them in and prevent any frame flexing. You can get aftermarket factory type or aftermarket tubular. These came on 4-speed cars.
 

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With nice rear brake lines, rebuilt wheel cylinders, & a rear brake hose made in this century, the method Jeff (GTO Junior) notes works very well. Have been using that method for the last 25 years. It's quite speedy, if one has the right tools laid out. When installing an A-body rearend, I use a pair of old blunt Phillips screwdrivers to guide each of the upper control arms onto the bushings in the upper housing, then i come back in with stock upper control arm bolts. With the bottom of the rearend center hsg cradled on the large cup of the floor jack, I carefull lift, & always attach thè upper control arms first, then the lowers, then each spring & shock.. Another trick, typically, will use old coat handlers to suspend the loaded backing plates. With a good floor jack & pair of HD jack stands, can usually swap out a GM Abody rear in an hour, hour & 15 tops
 

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Discussion Starter #7 (Edited)
I finally had time to get the wrenches today to get the brake lines off. Super easy once that was done.

Anyone have tips and cleaning it? It's covered in oil, dirt, and some weird spray on undercoating that a previous owner added.

Is it safe to pressure wash if I cover the ends and vent port?
 

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A good soak with degreaser / HD cleaner then a pressure washer would make quick work of it.
But the old hose and wire brush work too.
Yes try not to flood the Vent and/or tube ends.
The vent is just swedged into the tube and can be carefully wiggled/twisted out and some sort of plug used while cleaning.
 

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Discussion Starter #9
Finally had time to finish cleaning and priming this thing. That caked on grease was a PITA.

Can anyone help me with part numbers for the axle bearing and seals? I’ve seen a lot of conflicting info online.

It’s a factory 10bolt 8.2” BOP rear end with the bolt on axle shafts. Bearing is on the shaft and seal is in the tube.
 

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depending on the nature of the caked on crud, i have had luck using household oven cleaner...it is nasty, use goggles and gloves. oven cleaner is a formula with a base ph...it will mercilessly attack any acid ph crustiness....good luck...
 
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