I was at all local auto parts stores around my house and there is not too many choices for gear oil, specially 75W90. some places have their own store brand in that weight, but I don't know if I want to put some cheap no-name gear oil in my truck. the only convensional name brand gear oil I found was Valvoline. even that was $6 a quart. what do you guys suggest and where can I find it?