My 04 F350 is @ 160K don't know if man.trans & axle have ever been serviced. Stoped at dealer, talked e'm into running OASIS report & asked for quote to service them $350, thanked him and left.
Don't know capacity of them, first question 6 speed & rear axle qts
Anyone know anything about this?
Royal Purple® Synchromax ® Manual Transmissin Fluid
What is best for rear axle?
Rear axle takes a synthetic 75w-140 fluid. I would stay away from Royal Purple, they make their stuff thinner to get better mpgs, but it doesn't protect as well. Mobil 1 is good for gear oil, another great one is Amsoil Severe Gear, but Mobil will be easier to find.
Your transmission takes Mercon V ATF, I would go with a synthetic variant like Mobile ATF (Mercon V rated). Put the same thing in your transfer case.
He said he has a manual transmission. Only the 5R110 automatic transmission requires Mercon SP.
To the OP, I believe the Mobil 1 75W-140 already has the friction modifier in it. You can try it without adding it, and if the tires chirp while making tight turns on pavement, then you need to add additional friction modifier.
Yeah, you won't need the friction modifier. Everything else sounds like you're good to go. If you do the front axle later, go with 75w-90 Mobil 1.
I can use it on my 94 F350, changing rear axle now, 437k it is so loose that sensor can't pickup for speedo, coasting gears move back then it works.
Front axle not an issue, 4 wheel drive all at rear. Thanks