C3 shock absorber length

[Donald G.]

I have just installed new Delco shocks on the rear of my C3 project and find that the driveshafts now bind at the differential flanges. Obviously the suspension drops too far.
Does anyone know the correct extended length for these shocks?
Thanks,
Don

[Harmon C.]

Put the wheels on and set it on them they all hit *NM*

[Donald G.]

Re: Put the wheels on and set it on them they all

I realize that these things are crude but surely they cannot be THAT crude.

[Terry M.]

Re: Put the wheels on and set it on them they all

I don't know about crude, but my 1970 put the half-shaft universal joints in a bind when I rotate the rear tires while it is raised on the lift using the chassis for support. Never been apart. As Llyle says: "It's the nature of the beast."

[Michael H.]

Re: Put the wheels on and set it on them they all

Not sure about C3 but an old friend, Paul Adams, once told me that only original assy line rear shock absorbers on C2 limited the travel enough to prevent the problem that you describe. I've never actually tested/researched this but I believe he's probably correct. It would be interesting to know for sure.

[Mike McKown]

I don't know the assembly process but

consider this: If the engine/transmission was decked to the chassis with the rear suspension hanging in the free state, how could you rotate the driveshaft to locate the spline engagement of the yoke to the output shaft on the transmission? It'd be mighty tough if you couldn't roll the drive shaft a little and you couldn't if the halfshafts were bound up. For that matter, it would be a little awkward to install the driveshaft to the differential yoke.

Another example there again not knowing the process: Were the brakes checked with a torque wrench applied to the axles while a pedal pusher pumped the pedal? Wouldn't work if the halfshafts were bound up.

Maybe these problems did arise and the early '63 axle flanges were changed as a result? Make sense?

[Terry M.]

Hmmmmm

Good point Michael. I'll have to check the operation with the original shocks on there -- I have had them off and on several times, so I better check it both ways to be sure. I can't now recall which shocks were on when the binding occured. I hope I remember when spring time comes to Illinois.

[Michael H.]

Re: I don't know the assembly process but

Good point Mike. Yes, the shaft/diff flange would probably have to be rotated just to install the drive shaft/"U" bolts and nuts. It certainly wouldn't rotate if the shocks allowed the control arm to travel to the point of shaft/flange contact.

At the St Louis plant in the 60's, brake test was done after the body landed on the chassis. In later years, the complete hydraulic brake system was filled and pressurized before the body was installed on the frame.

[Michael H.]

Re: Hmmmmm

Thanks Terry, let us know what you discover. I think only winter and August in Illinois. No spring.

[Mike McKown]

Brake test

My point about the brakes is even though the body was on the frame,if the suspension wasn't collapsed at this point, the rear wheels couldn't be torque checked. I would think the wheels would be off the chassis at the point of brake check with the torque wrench.

[Michael H.]

Re: Brake test

Interesting that the very next step in the Corvette assembly process after the body was installed was the installation of all four wheel/tire assy's and the car landed on it's feet just moments later. From that point forward, the car was on a pair of moving tracks so no brake test would have been possible on this line. I know there was no brake test prior to body drop on the chassis line. I wonder if the test that you mention was pass car/truck?

I would have to think that engineering would design the rear shocks to limit susp travel and prevent the shaft/flange contact problem but possibly they didn't think it was important? Pretty sure I would have.

[Terry M.]

Re: Hmmmmm

It is actually pretty close to Spring weather here for he last couple or three weeks, but no way is the Corvette coming out -- it still knows the calendar. School is closed anyway, so I can't get it on the lift just now. I have a couple of things to check on the chassis in the coming months -- just have to remember them all -- See you in a couple of weeks.

[Dick W.]

Re: Hmmmmm

I have an original '72 on the lift right now. Still has the '71 dated shocks on it. The shocks limit the travel on the trailing arms, but allow for joint bind.

[Donald B.]

Re: Hmmmmm

When I lived in the Chicago suburbs we referred to the weather as Winter or Road Construction.

[Stephen L.]

Re: Hmmmmm

My 67 has the original shocks on it and there is some bind/interference on the half shafts with the wheels off the ground; however you can still rotate them fairly easily.