Manual Transmission Lube

tdub · Post by **tdub** » Sun Jun 03, 2007 8:49 am

I just had a tranny rebuilt for my 84 Bronco II. The place that rebuilt it said to fill with 10W 40 engine oil for smoother shifting. The last time I did that , the tranny failed after 9000 miles. What is the best fluid to use? I drive mine both on highway (mostly) and on dirt roads (occassionally). Thanks!

BDEUCE · Post by **BDEUCE** » Sun Jun 03, 2007 9:35 am

i beleive in my fm146 i have 80w90 gear lube and half a quart of dexron/merconIII atf in it "for smoother shifting".

what does the haynes / Chilton say?

Paul · Post by **Paul** » Mon Jun 04, 2007 7:05 pm

haynes says tyo use an 80 weight gear oil in manual transmissions and to use dexron oil in the transfer case, 30 weight oil sould casue it to fail, i always lucas oil stabilkizer in mine about half a quart and it does just fine the advantage of lucas is that its pure petroleum, it will mix with any petroleum oil even synthetics... but in my opinion its the best to use... but its a little more expensive than some of the alternatives.