[buzzinhalfdozen]

[QUOTE=1320racer;416413]I must have missed the memo, because to the best of my knowledge the Mobil 1 Synthetic gear lube that I have been using for over 2 decades and over 5000 passes in 2 cars is GL-5 and by some miracle the R&P in my 9" housing under my Firebird in which I 60 foot quicker(1.17 best) and runs quicker than most posting here survived weekly racing for 4 years and over 700+ passes before the pinion gear started to fail.[/QUOTE
Man some things never change....first off you never stated, pro or street gear. If it's a pro gear I'll have to disregard your posts as they will not survive that number of runs they are way too soft. After assembling hundreds of gears of all types, 10 bolts 12 bolts, 8.8 & 9inch for every thing from a 12 second bracket car to 6 second top sportsman rides, the trick to making them last is proper gear prep and assembly. From my personal experience a pro gear at it's best will go a few hundred runs, it will eventually merely wear out very few actually break, unless the warning signs were ignored. Street gears now many hundreds of runs can be made on them and most meet their demise in the same manner....broken R&P teeth. A properly set up gear set will survive most any lube you chose to use (within reason) however the original question I believe was is there a performance gain to be had from synthetic lubes. Looks like a few responded with their actual experiences with different lubes and 1 response merely referring to how he thinks it should be done. BTW the first question I ask someone wanting a gear set up is "what's it being used in" the final assembly is different car to car.