CK5
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1973 C10 "The Purple Truck"

Basic build
We got the gears in this weekend. Nate helped me with the final setup. It all went pretty well until it didn't.

I got to make a couple of tools. The first was a yoke puller.

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I had all new bearings but we wanted to pull the pinion bearing off to see what shim was under it and to use it for a setup bearing. I ended up making my own separator.

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I clamped the 2 pieces of angle together and put a 2-1/8" diameter hole with the center where to 2 angles meet. Welded one of the angles to the "feet" and used the clamps to hold them together. It worked great to pull the old bearing off.

These sanding wheels in a drill worked great to make the setup bearing. Used the 60 grit and found the diameter that was just a little bigger than the bearing.

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We had a perfect pattern with the setup bearings, but when we swapped it over to the new bearings it didn't quite transfer. We pulled the new bearing with my homemade separator and it worked like a charm.

It all started downhill when we pressed the new bearing back on with the revised shim. It didn't press on as smoothly as it should have but it went on all the way.

We got an "good" pattern, but we decided to shoot for a "great" pattern. However the bearing that didn't press on smoothly didn't want to come back off and we bent my separator. There's such limited space under the bearing, you can only fit 1/8" thick steel. Plus the new shims had a much larger OD which I think also got in the way.

We stuck with the good pattern and buttoned everything up. I told Nate it was telling us that was the shim it wanted and didn't want to give it up so we should stick with it.

So far it's working right with no noises. If I do gears again, I'm getting one those clam shell bearing pullers to make it easier to pull the pinion bearing off for changing out shims.

The 3.73 gears are SOOO much better than the 3.08s. It just gets down the road like it should. The higher stall converter with the 3.08s felt like I was always starting up a hill or towing something heavy. It couldn't hold OD at 65mph if there was any headwind or small rise in the road.
 
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I've noticed my rear brakes lock up before the fronts. Can I just put in an adjustable proportioning valve at the master cylinder to fix this? Or is there more plumbing involved?
 
I've noticed my rear brakes lock up before the fronts. Can I just put in an adjustable proportioning valve at the master cylinder to fix this? Or is there more plumbing involved?
Are these still drum in the rear? If so, make sure they are adjusted up good. If loose they will lock up easily.
 
I have both a residual pressure valve and adjustable on the line for the rear on the jimmy. I couldn't remember if you did 4 wheel disc on that truck or not. Either way the adjustable valve should fix it. Then repeated skid tests.
 
Are these still drum in the rear? If so, make sure they are adjusted up good. If loose they will lock up easily.
I have both a residual pressure valve and adjustable on the line for the rear on the jimmy. I couldn't remember if you did 4 wheel disc on that truck or not. Either way the adjustable valve should fix it. Then repeated skid tests.
It's disc front, drum rear. I'm thinking changing the master cylinder to a newer version and the wilwood calipers probably changed up the balance.

It was fairly easy to slide the drums off when I did the gears. Since I set the parking brake every day to park in the driveway at home, I thought they would be adjusted well with the self adjusters.

Does the adjustable proportioning valve replace the combination valve on the front crossmember?

Put a load in the bed, or hook onto a trailer.
:D
I looked, it doesn't have the load adjusting deal on the rear brake line. My first thought had been I had one and it was being actuated because I had lowered the rear suspicion.


Needs 18" wide tires and tubs in the back
I wouldn't mind some 10" wide wheels.
 
Does the adjustable proportioning valve replace the combination valve on the front crossmember?
We did a disk brake conversion a few months back and we put the adjustable proportioning valve up near the master cylinder so that it was easy to access and adjust. We didn't replace the combo valve, but we did pull the guts out of it.
 
I was thinking it would be nice to have the adjustable unit up by the master cylinder for convenience.
 
I put mine on the frame after the factory valve. I can reach under and adjust it without popping the hood. But like others have stated, once I adjusted it initially, I never touched it again.
 
I should say that I should dial mine in depending on what I am doing. Normal street driving or wheeling it is good where it is. When I get on what little throttle I have, on curvy dirt roads, especially down hill, I will heat the front brakes to the point of smelling them. Not enough rear brake for the whoa-ing that I am asking the 7000 pound truck to do on stock front brakes.

Coming down from La Salle mount following Brent, they had a funny smell to them. I won't say how fast we were moving, but the rear end was coming around in every corner. And stayed there until the road straightened back out. I have no idea why this was happening.
 
So do most people leave the factory combination valve untouched, or do something similar to what @ashman memtioned?
 
I have rear discs and did a disc/disc combo valve from Summit that didn't really change anything and then added in a manual one from jegs up by the master.
 
So do most people leave the factory combination valve untouched, or do something similar to what @ashman memtioned?
I would make sure that the residual pressure valve is removed at minimum. They are supposed to have 10lbs for drum, which is too much for disc, from what I have read.
 
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