Penn Grade 1 GL-4 Gear Oil SAE 80W-90 - 1 Quart Bottles (6 Pack) For Classic Transmissions

This Penn Grade 1 gear oil is specifically made for classic cars and older manual transmissions.

It's SAE 80W-90 weight and meets GL-4 specifications, which is important because it's designed to work with the brass, bronze, and copper parts often found in older transmissions.

Unlike GL-5 oils, this one doesn't have the friction modifiers that can mess with synchronizer performance.

It's made from premium mineral base stocks with special additives that protect those soft metal components.

Comes in a 6-pack of quart bottles, so you've got enough for a transmission service plus some extra.

Just note - it's not for limited slip differentials or where GL-5 oil is required.

But for classic cars with manual gearboxes, this is the good stuff that enthusiasts have been using for years.