67-72 Control (A) Arm Bushings?

[DJ_Baar]

I got a set of '71 2500 (3/4 ton disk brakes parts, like spindles, & control arms, etc.,) when I bought my '67 Chevy C20 (3/4 ton with drum brakes), a couple months back.
I am in process of the conversion & repairs to suspension/steering. I already installed a new CPP master cylinder & booster, and now working through changing suspension/steering changes to accommodate '71 spindles, etc....
I have a couple articles like http://www.earlyclassic.com/tech.asp...20That%20Truck and http://www.classicperform.com/discdrop.htm . (I don't care to drop this truck.)
The control arms from '71 are in better shape than what is on the truck so opting to go with them. The lower A arms still have shafts in place and frozen. I started with 3/4 inch long ratchet on both then went to impact and got one side to move on one side with impact but other side froze good. So you see in picture soaking with penetrating oil. Is this normal and recommendations on changing bushings on these.
One picture is existing drum brakes (only shocks removed) and A arms soaking w/penetrating oil.
I will further clean and paint before install with new bumpers etc.... I am replacing power steering control valve, power cylinder, and pressure hose, along with new inner (for 67), outer (for 71) tie rod ends, and sleeve (for power steering).
Any helpful feedback is appreciated. I looked online and didn't find much help so far.

R/
DJ

[DJ_Baar]

Have more time today and looking for more answers found this thread:
http://67-72chevytrucks.com/vboard/s...d.php?t=508095 and then this one even better with reference to disk brake conversion too:
http://67-72chevytrucks.com/vboard/s...d.php?t=460890
Second thread explains a whole lot more of what I am doing & how I am doing it.
Added more penetrating oil this morning before leaving for work - got to get the old ones out first ;-)

[toolboxchev]

Those things go in with 200 or so door pounds of torque. That should explain things

[un4gvn!]

What is (door) pounds of torque? Do they make a tool to measure this?

[DJ_Baar]

See attached pages from 1967 Factory Chassis Service Manual. Note there is a difference between C10 (1/2 ton) and C20 (3/4 ton) trucks.

I ordered replacement bushing with both upper & lower control arms to replace old ones. Uppers are out and still soaking lowers with penetrating oil till next weekend.



R/
Dave

[Steeveedee]

You're gonna need a lot of muscle. Mine were so tight that I had to use both arms to get them loose. Putting them together is a one-arm deal, though, if you use an 18-inch long torque wrench. I stood on the A-arms. I didn't have any vise setup that would accommodate them.

[davepl]

This is one area where the difference between a C10 and a C20/C30 really shows up. The HD trucks are pretty beefy in this regard.

[GR8-68]

And this is why we love this forum, always good information coming out

[tdangle]

I broke mine loose while still in place on the truck. Way easier than after removing the a-arms

[DJ_Baar]

Attached is torque spec from second volume of the 1967 Chevy Truck Chassis Overhaul Manual. Note the smaller value for replacement control (A) arm bushings - BIG difference New to Old (280 to 135) on lower ... but that's OEM spec. Now wonder getting the old bushings out of ('71 "Donor") lower A Arms has been so difficult.

Looking forward to working this project this weekend and will try to get more pictures to share later.


R/
DJ

[chevytruckguy70]

I also replaced mine while they were still mounted in the truck, but even with that I had to heat them up first. I'd recommend heating with just a propane torch making sure not to warp anything.