The Stovebolt Site Forums The Shop Area Driveline Pinion shaft shims

As a follow up to "is my rear end junk?" post...It was and I found a replacement 1954 rear end that already had the 3.55:1 gears...BONUS! But I have to use my 1940 torque tube and third member with the 54 banjo housing and aftermarket ring and pinion gears. The trouble is, I don't have the instructions that come with the gears when you buy them. I have read all of the available tech tips and my 1940 shop manual and I am confident of all of the steps except shimming the pinion shaft. How do I determine the proper shims? is it strictly bluing? And is it only after setting the backlash or is there a preliminary check that I can make to get it close? surly the shims will have a huge effect on the backlash.

Thanks, John

1954 manual,
http://chevy.oldcarmanualproject.com/shop/1954truck/54ctsm0406.html

The shims set the pinion depth, so the first install is a test to see if you need to raise or lower the pinion in relation to the ring gear. Depth is related to tooth pattern. If the pinion is not marked ( the late model ones are ), then install thin one and set up the whole assembly and check the tooth pattern. Be sure to tighten all the bolts and nuts, set back lash, and bearing preload. If the tooth pattern is off, then you need to remove or add shims to correct it.

The '54 manual should tell you which way to adjust the shims for the pattern you get. For that matter, about manual should have tooth patterns in it, and the newer ones probably have better pictures.

Joe

Thanks Joe,

That's a lot more info then what's in my my 40 manual which doesn't have pictures of the gear contact pattern. I think I can picture it but would like to see photos if anyone has any.

Nice 37. Do you have a write up on your restoration?

John

Here is GM film strip photos of a 1952 Chevrolet Rear Axle Overhaul
for the passenger car and 1/2 ton truck.
The film strips were used by GM Dealer Mechanics.

Here is one of the photos showing the correct Tooth Pattern on the ring gear.
Good stuff.

That is awesome! Thanks Jorb.

There are video`s on YouTube showing the rebuild of differentials....The one that I just recently watched was from " ERIC THE CAR GUY" Very informative.
He explained the pinion shimming and showed it being installed.
I highly recommend seeing it. I believe he was working on some 80`s Ford...
but the process is the same...