Since I've been reading up on G506 rear axle (banjo type) I of course came across several ramblings made by the head poster of blather:
Making the ASININE statements:
Re: G-506 Chev. rear axle outer lock nut w/seal.
Postby Ben Dover » Wed Jul 18, 2012 2:34 am
The Metal Gasket is a must, the problem was motion which ruined the threads in the hubs.
And
Re: G-506 Chev. rear axle outer lock nut w/seal.
Postby Ben Dover » Tue Jul 24, 2012 2:13 am
The Factory Bolts do not have a precision fit shank, the Terne Plate Gasket is the medium that helps prevent motion, many do it your self owners choose to juse a paper or or silicone which does not contribute sufficient friction. This has been an age old problem since the trucks were first released to the civilian market 66+ years ago. Elongated holes and worn threads are the norm for this abuse. It is a chronic G-506/G-508 Problem. Best to install a fresh terneplate gasket each time.
NOTE:
You will notice reference to this metal gasket being aluminum in the TM9 and 10 Repair Manuals. The term Terneplate does come up somewhere in the technical information. on the Banjo Axle.
More BS from the head BS'er
Re: CCKW open cab on G-506
Postby Ben Dover » Fri Apr 20, 2012 7:54 pm
Bolts for rear Banjo Axle Flanges on Chev 4X4 and CCKW are 7/16" X 1-3/8" NC and OEM have a special shoulder. They must be installed using OEM Terneplate Gaskets, use of paper or Silicone will allow them to slip and enlarge the bolt threads in the hub. This has been a problem forever with trucks repaired without using the proper rear axle gaskets.
It seems that Bend Me Over thinks that the metal tern plated gasket is there to somehow stop the axle from 'slipping' around the hub flange and somehow preventing the elongation of the hub bolt holes.
REALLY?
A thin coating of tin/lead is going to stop the rotational forces of the axle from putting a tangential force on the axle bolts and stop the bolt holes from elongating?
REALLY?
So what is Terne plating?
"Terne is an alloy coating that was historically made of lead and tin used to cover steel, in the ratio of 20% tin and 80% lead. Currently, lead has been replaced with the metal zinc and is used in the ratio of 50% tin and 50% zinc. This alloy has a low melting point approximately 360 degrees Fahrenheit."
Lead is a very, very, very soft metal. Anything that is 80% lead will smear like warm butter. What 'friction' is it supposed to generate?
As stated the Terne plate is nothing more than an ANTI-CORROSION coating. Its not a miracle friction material.
So why are some hub bolt holes so torn up? Misuse (overloading truck) and improper maintenance (my G506 has STUDS, not BOLTs holding the axle to the hub) and any number of other things that people do to fix a truck to get back to work. They can be fixed (either with helicoil or weld up then drill/tap to size.