69volunteer 84 Report post Posted April 17, 2012 What weight gear oil on a 8" rear end? Service manual says 4 pints but gives a ford part number for lubricant. Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted April 17, 2012 I've always used 90w. Quote Share this post Link to post Share on other sites
MikeStang 247 Report post Posted April 17, 2012 I use 80W90 with some of Fords limited slip additive....its a small little white 6 oz bottle...Its some times called friction modifier i think. Just put that in there, and fill with oil till it just starts coming out of the hole your filling it in. Bada Bing Bodda Bang Mike Quote Share this post Link to post Share on other sites
StephenC 10 Report post Posted April 17, 2012 I use 80W90 with some of Fords limited slip additive....its a small little white 6 oz bottle...Its some times called friction modifier i think.Just put that in there, and fill with oil till it just starts coming out of the hole your filling it in. Bada Bing Bodda Bang Mike This ^ I've always used 80W90 LS Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted April 17, 2012 My 69 owners manual shows Ford Hypoid gear lube, Ford part no. C6AZ-19580-B = 90W gear oil. I didn't see where he mentioned a limited slip. Quote Share this post Link to post Share on other sites
MikeStang 247 Report post Posted April 18, 2012 I always put the additive in no matter what lol, just a habit I suppose or it could be that all the cars I have owned had posi in them...regardless it won't hurt.....80w90 with additive and u can't go wrong Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted April 18, 2012 Mike, where do you get the additive? Online or local? Quote Share this post Link to post Share on other sites
MikeStang 247 Report post Posted April 19, 2012 Go to your local ford dealer.....they still keep the stuff believe it or not....same for Chevrolet limited slip.....or u can get some at auto zone most times.....or you can get it on line....any of the rear end shops online keep it too....i soak clutches in a mix of 80w90 and additive before rebuilding...then just pour it back in bottle and squirt in rear end lol....ford dealer is gonna be the easiest.....just tell em u need some limited slip additive for a rear end....if their worth their salt they will know what u need Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted April 19, 2012 Thanks Mike. Didn't even think of the dealer. Quote Share this post Link to post Share on other sites