Hello this is my first post but I have been a fan for awhile.I have another gear question.I have an 04 f250 3.73 open rear with 285's on it.I have purchased 4.56 ring pinion for the rear.My question is basicially what is the bare essentials to get the swap done.I understand that I should have shims,extra pinion bearing to grind out for fitting,and a pinion depth gauge.I am tring to do this on shoe string budget,I still need to get gears for front.My last truck was a 7.3 and the one before that was v10 with 4.30s I plow and tow often,so I am anxious to make the swap just tring to get as much info as possible. thanks.

 

A ring and pinion change is a very "in depth" process of measuring and trial-and-error slip fitting. You will need a dial indicator. When I did mine, it took me about 2 days to do both axles due to the measuring and whatnot.

Remember to NOT use 4wd when you actually get the rear gears installed. Damage WILL result.

 

yes I am awhere to engage 4wd until they match.I do plan for I2-3 days and I do think if I take my time it is something I am capable of,also it is just not in the budget to pay to have done. thanks for reply

 

For the Sterling in the rear, what I'd do is put the rear pinion bearing on the pinion gear together with the shim pack from the old pinion. The pinion depth gauge is a pre-set tool that will tell you what shim pack to put in the rear. They used the same tool at the factory to setup the original gears, so if you didn't grenade the gears and/or overheat the pumpkin, the depth shouldn't change.

After it's all back together, check the backlash AND the gear contact pattern. The pattern should be a nice oval shape right in the center of the ring gear teeth, if not slightly to the outside of the teeth. If you don't get that nice pattern and a good backlash setting, you then need to pull it apart and start moving things around. Which is lengthy and requires LOTS of patience. Lots of times, like I said, if the unit hasn't been busted to pieces or overheated, the pumpkin won't be stressed and the setup will be perfect on the first shot.

Getting the pinion preload correct is the tough part.

The Dana front-end, well, the preload is setup with shims instead of a crush-collar, and the pinion depth (according to my Ford service manual) is also setup with a pinion depth gauge. So, again, use the old shims, reassemble and check the pattern.

DO NOT use a hammer on the differential to get it into place, use a spreader or make your own. It makes it a lot easier to get together and you don't run the risk of ruining the bearings.

 

Thank you very much for the insight that makes it seem a whole lot more clear.