Preservation of a 68 Camaro

[Too Many Projects]

The forward cabin floor on my car is original and no reinforcement plates. I replaced the entire trunk floor assembly from the forward floor back, saving the original frame rails.

[SMS]

Very timely. I just shot my 68 wheel well undercoating using in part your photos as a guide. Thank you!

[BJCHEV396]

Good stuff! Welcome back Darrell!

[cook_dw]

Diff cleaning and preserving is now complete. Installed pinion races and carrier bearings (not pictured and previously axle bearings and seals). Once I get the inner pinion bearing installed I will start the reassembly process. I've decided to go with the solid pinion sleeve and I'll walk through how I set it up etc once the time comes.



Photos 937 - 940 - Diff during the heating and coating of Cosmoline Rust Veto & RPM (Rust Preventative Magic). I heated the differential with a heat gun and applied the mixture with a paint brush and kept heat on it while it cured and leveled out.



Photos 941 - 942 - Center section and the casting date now revealed. C 21 8



Photos 943 - 944 - Perches and their markings of LH and RH

[cook_dw]

Pinion bearing installed. I removed the old one with a Dremel tool and metal cut off wheel (or you can use an air cut off; I used E-Z lock wheels), a hammer and chisel. Also note the pinion shim thickness. Since I have changed gears I reused the old shim for a starting point. For this setup it was a 0.028" shim. Next I threw the pinion with shim into the freezer in the frig here at work (mini frig). Then I set the bearing up with a heat gun applied to the face side of the bearing (the point that makes contact with the shim on the pinion. After a hour in the freezer and roughly 5 mins under the heat gun the bearing dropped right into place. You could also do this with the carrier bearings and pinion races. However I used a brass & steel punches to knock those into place making sure they bottomed out.

Photo 945 - Pinion with bearing & shim installed.

Photo 946 - I did get a little fancy with the stand and thermal imaging camera and magnets but you get the idea.

[1967Z28]

Darrell, any consideration to finding a more date appropriate and application appropriate rear axle since this one is not original to the car? Just curious.

[cook_dw]

It would be different if I had the original engine and/or trans. But since all 3 are MIA I did not feel the need to replace the diff. At least at this point.

[1967Z28]

I can understand that. Thanks.

[cook_dw]

Started cleaning the yoke and I think my evaporust has fought the good fight but its done. I'll be ordering more in the following days.

Photo 947 - Yoke before cleaning


Photos 948 - 950 - After cleaning and evapo. Still not happy with the results so I am gonna give it another cleaning before the rebuild. Note the yellow marking.


Here is why I said I needed new Evaporust. After sitting for 48hrs this is the result..

Photos 951 - 952 - Backing plate

[cook_dw]

Finally got the pinion yoke cleaned completely and now its time to set up the diff.

Photos 953 - 956 - Yoke



I decided to go with a solid pinion shim for this application. I measured the old crush sleeve and it was 2.283 - 2.278". I added shims to the sleeve to hit right at 2.282" and left the pinion seal out while I attempt the setup. Overall the carrier shims were 0.242" on the left and 0.063, 0.063, 0.098" on right of the carrier looking at the diff. Overall total was 0.476". the final setup was on the left 0.242 & 0.013" and the right side was 0.160, 0.063" for a total of 0.0478". This put the backlash right at 0.006 - 0.007". These are used gears and do not show the same pattern as new gears but this is an acceptable wear pattern (confirmed by a couple of folks that have experience). Pinion shim could have been a little thicker to deepen the pattern engagement but for all I am happy with the look. Worst case once the car is up and running and if there is a whine on decel then I will go back into it.

Photos 957 - 958 - Pinion installed with the correct resistance on the bearings. I've always gone off of feel and it hasn't failed me yet. Note: the carrier shim photos are not the final shims used for the setup. Just ones I tried using to accomplish the correct backlash.



Photos 959 - 960 - Carrier bolted down using a crossing pattern and then using a magnetic base and dial indicator confirmed the backlash was 0.006 - 0.007".



Photos 961 - 962 - gear mesh


Photos 963 - 965 - Pinion seal, "New" aluminum diff cover, vent and yoke.


Going today to hopefully get gear lube, posi additive and evaporust should be delivered today or tomorrow.