Does extra differential fluid cause issues?

[Bikerjon]

8 hours ago, Interleukin6 said:

Let me ask another questions. This was first time for me to change the different fluid in my life. My GM one has a paper-like gasket already stuck on the mating surface of the diff. I used a razor blade to take it off, making some mild scratches on the surface. I read later these scratches would cause leaks eventually… then I got scared…. So far nothing has been dripping for 3 days. I see many are using a flat head screwdriver, razor blade, or metal scraper to take off the stuck gasket but some say that only plastic one should be used because plastic does not scratch metal… if it starts leaking, a RTV sealant will be the one rather than OEM gasket? Sorry for multiple questions. What are the pros and cons  of gasket vs RTV sealant? Thanks.

Don't worry about a couple of scratches on the metal when you remove a stuck on gasket. It happens all the time. Personally I try to always use a new gasket (when available). If you cannot get a new gasket RTV works fine. The important thing is to thoroughly clean the surfaces of old gasket material and any grease or oil.

[Black02Silverado]

To me, the reason AMSOIL has mad the 75w-85 is due to market demand.  The average person wants to use what the manufacture recommends. Now, there is a difference in the formula for sure. But to me it is more on the lines of CAFE than anything.  I've been using the Severe Gear 75w-90 when it called for 75w-85 and have had no issues.

 

Trying to squeak out every little bit of economy is the main goal for manufactures to show they are doing what they can to improve it.

 

Even the AMSOIL look-up guide showed the 75w-90 could be used. 

 

Just like the VTwin 20w-50 oil can be used in all three sumps. But then AMSOIL came out with a specific transmission and Primary fluid and sales increased.  Marketing!!!!