The manual calls for ATF but the dealer said to use 85W90 gear lube in the front diff of the transmission. The tranny code is A541E. Which would give me better protection?
M1 ATF is what I used in my dad's Lexus ES300, and we were both pleased with the results.
There are, however, oils designed with similar viscosity to ATF, but with better additives for gears. Royal Purple Syncromax and Amsoil Syncromesh 5w30.
Either way, that differential will last a long time.
Interesting--I own a 97 Avalon (172K) also and have never heard this. I put RP ATF in the differential 25K ago, but cannot tell any difference between that and the NAPA ATF.