New to HD and would like to use gear oil in the trans .However, not comfortable if there is ANY yellow metal in there even though most modern gl5 gear oils claim to be safe. I am not interested in responses such as " I've been using gear oil for 10,000 miles with no problems " while this is fine it only indicates all seems OK .I have asked at 2 different HD shops ( one that uses redline shockproof ) and the response is it should be fine. So does anyone know this answer as fact? Thanks

 

Not an issue any more has not been for some time. If you sleep better running a GL5 in a gear box go for it.

 

What prompts you to ask about 'yellow metal'? Presumably that refers to the copper alloys including brass and bronze used for bushings, which have been used in transmissions forever. What model and year is your bike?

 

2014 Limited. I ask because I would like to use "gear oil" in the trans .However gear oil contains sulfer that attacks yellow metal. Most modern gear oils now buffer that sulfer so it is less damaging to yellow metal but I'm not sure if " less damaging" is good enough for me. Using a multi viscosity ENGINE oil in a HD trans with a one quart capacity is crazy but would like to know what the ACTUAL RISK of a gear oil would be

 

You asked us not to tell you this, but I've been riding for over 50 years and way over half a million miles......

 

Yeah, you don’t want to hear it. But, welcome to the forum where we’ll tell you what you need to to hear.

There are many high quality purpose made lubricants for our constant mesh transmissions. People have put many miles on their 6 speed transmissions using BelRay, Redline, etc.

Many here will swear by synthetic motor oil in their transmission. But, I’m not one of them.

 

What do you call yellow metal? I know there's lot of silver metal, don't know about any other colors.

 

This comes from another of those they say things. Old gear boxes and metal used in them reacted with GL5 lubes . When using GL5 Syn became the big new thing for motorcycle gear boxes the internet was on fire with it. To this day have not met the real person that had a modern gear box trashed for a GL5. Truth is GL 1 are just fine for most transmission. Remember the green GL4.
This is were a lot of it came from "nissan requires gl4 in our transmissions due to yellow metals used in the transmission." It was said that GL5 caused corrosion when it was in contact with these yellow metals.
Look closely many GL5's now say yellow metal safe and the issue was long ago put to rest.

 

I have been using Spectro platinum 75W140 Differential oil which is a GL-5 in a Ford Toploader 4 speed for the past IDK say 20-25 years. The transmission has a lot of yellow metal...no issues, none.

Ken

 

Many people will tell you that you need to use gear lube in a Harley transmission, but I bet not a single one of them has seen a worn out gear, no matter what type lube was used (as long as it did not run dry).