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Owen wrote: "A valid comment about the compatibility of some EP gear oils with transmissions/ODs with bronze parts; "

I've heard the same thing. I don't really know. There is one part of this raher widely accepted claim that does not make sense to me. The standard off-the-shelf EP gear lube was used nearly exclusively in stick shift transmissions and axles from early 50's thru late 70 that i know of AND the synchro rings were bronze. If they weren't bronze then brass maybe. Also many trans' had bronze thrust washers.

I've used the standard off the shelf gear lube in my 48 Chief with bronze (reproduction) cluster gear bushings and NO adverse effects.

The EP claim damaging bronze parts was later explained to me by a layman collector to be limited to very early 1900 - 1920 axles and transmissions. Perhaps there was some change in the amalagam of bronze production early 20th century. I don't really know for sure.

I suppose the best way to dispell the EP gear lube/bronze incompatability would be to drop a bronze piece into small jar of EP gear lube and see what happens over the course of a year or two.

However, as Owen notes about his car then that is probably a good enuf test for me to accept the EP gear lube as compatable.

I am suspicous that any such NON-compatability claims are probably limited to very early 20th century units.

Dear All,

OK, I must not post when I am tired. I am an idiot, and I apologize. I got all muddled about EP versus non-EP and GL-4 versus GL-5.

It was GL-5 that I meant to talk about. I have some references that state GL-5 rated gear lube, under high, but reasonable, temperatures can corrode 'yellow' metals. It is therefore recommended to use only GL-4 rated lube in ones older cars.

I really apologize .



Tom