Question about 6 speed transmission fluid change...

[LAP1DOUG]

Personally, I would (and did) go for convenience, and head on down to the local auto parts store where they have a great selection of excellent hypoid oils. I like Valvoline Synthetic combined GL-4/GL-5 rated. Don't get just a GL-5, get the combined rating.

As I understand GL-5 is the best for ring & pinion gear loads, but GL-4 is best for synchonizers. With a transaxle like we have, you would like to have a combined rating.

Also, if you have a torsen type limited slip, you probably don't want the Royal Purple or Red Line super exotic type oil that has some kind of friction reducing semi-solid beads in it. As I understand, that can reduce the effectivness of the limited slip.

[jsceash]

Originally Posted by LAP1DOUG

Personally, I would (and did) go for convenience, and head on down to the local auto parts store where they have a great selection of excellent hypoid oils. I like Valvoline Synthetic combined GL-4/GL-5 rated. Don't get just a GL-5, get the combined rating.

As I understand GL-5 is the best for ring & pinion gear loads, but GL-4 is best for synchonizers. With a transaxle like we have, you would like to have a combined rating.

Also, if you have a torsen type limited slip, you probably don't want the Royal Purple or Red Line super exotic type oil that has some kind of friction reducing semi-solid beads in it. As I understand, that can reduce the effectivness of the limited slip.

I put this in in January then read all the you won't be able to shift in the cold warnings. It was recommended by a person who track a car 6 to 7 times a year, and is connect to a dealership . It worked the same as the old oil. I felt no change. The 03 most likely had the Mobil PTX in it from new

[JFP in PA]

Originally Posted by LAP1DOUG

Personally, I would (and did) go for convenience, and head on down to the local auto parts store where they have a great selection of excellent hypoid oils. I like Valvoline Synthetic combined GL-4/GL-5 rated. Don't get just a GL-5, get the combined rating.

As I understand GL-5 is the best for ring & pinion gear loads, but GL-4 is best for synchonizers. With a transaxle like we have, you would like to have a combined rating.

Also, if you have a torsen type limited slip, you probably don't want the Royal Purple or Red Line super exotic type oil that has some kind of friction reducing semi-solid beads in it. As I understand, that can reduce the effectivness of the limited slip.

I just love gear oils with this supposed type (both GL-4 and GL-5) of API ratings; if you read up on what the specs actually mean, you would discover that what makes a given product a “GL-5” rated lube, prevents it from every holding a “GL-4” rating (the difference is an additive package specifically for improving the performance of certain types of limited slip differentials, but which is also known to attack certain metal alloys, like the synchronizer rings used in transmissions which require GL-4 rated lubes).

[Idaho Red Rocket 3]

Straight GL4 is how I interpreted the requirement. Lots of GL5 and GL4/GL5 around, but hard to find the straight GL4 synthetic around here. It took a little research time for me to find the straight GL4. Turned out to be at an Indy parts shop about 2 miles from my house. $11 per liter.