[Dave at Pelican Parts]

90-weight gear oil, about 2 1/2 quarts. I prefer Swepco 201, and it is recommended by a number of pro mechanics I know. That seems to be the most-common recommendation.

There is also one school of thought that any decent 90-weight non-synthetic is fine.

A few people feel that various synthetics (e.g., Mobil 1 gear oil or Redline MTL) are the best, but more people feel that synthetics do not let the synchros work correctly.

(Disclaimer: Pelican sells Swepco. But I've believed in it before I worked there.)

--DD