Do most of you guys just add an extra amount of oil to your manual trannys or do you add synthetic oil to it? My mechanic said everyone is changing to the new synthetic oil in their manual trannys.

 

which truck you talking about? you have quite a few listed there! I think on your older trucks you can use synthetic or standard actually up to you as far as I know. The newer ones need the synthetic because of the something to do with the internals or something along that line. But your older trannys should just be plain old gear mashers.

 

Go synthetic. It allows less change out therefore more miles and better lubrication.
Change it all out, just don't add.