[Gavin.212121]

I have a 1999 f-250 powerstroke and I've had to put it away because I cannot find what is the issue, while I'm driving it makes a loud clanking noise and is barely noticeable if I'm not on the throttle. When I get back on the throttle the clanking returns. I did look underneath it while it was moving and the rear drive shaft will do a 1/4 turn and then lock up and then it makes the noise and then will spin and do the same thing.. Is there a part that I can replace on my transfer case do I need to replace the whole thing any ideas please help

 

[dwright5460]

is it in the t-case or rear diff, 1/4 turn of free play is diff.

 

[Gavin.212121]

The whole drive shaft will do a 1/4 turn both in the rear diff and in the transfer case

 

[bugman]

You have to remember that the transfer case is also attached to the transmission so some of that slop could also be in the tranny

 

[klhansen]

The whole drive shaft will do a 1/4 turn both in the rear diff and in the transfer case

If the transmission or transfer case is in neutral, that would point at the differential, as that's the only thing that's held stationary (if the truck isn't moving.) I would remove the driveshaft (and check the u-joints) and then turn the pinion and transfer case yokes by hand. That should help you figure out whether you need to be looking at the t-case (or forward) or the rear differential.

 

[Gavin.212121]

The whole drive shaft will do a 1/4 turn both in the rear diff and in the transfer case

If the transmission or transfer case is in neutral, that would point at the differential, as that's the only thing that's held stationary (if the truck isn't moving.) I would remove the driveshaft (and check the u-joints) and then turn the pinion and transfer case yokes by hand. That should help you figure out whether you need to be looking at the t-case (or forward) or the rear differential.

Okay thank you I will check this tomorrow and get back to you

 

[Gavin.212121]

Got it on the lift last night and I spun the driveshaft in nuetrual and I could hear a whining noise from the transfer case... Thoughts.?

 

[Gavin.212121]

Took the rear diff case off and found the problem. Would it be easier if I just bought a whole new diff or can I replace the main gear and the pinion just as easy.. Also what would be the correct gear ratio to get

 

[bugman]

There should be a tag on one of the bolts that you removed to get the cover off of the rear end that will tell you the ratio and if it has limited slip. Also on the door frame you should have a sticker that will have the rear end code on. Get the code and then go here to see what it is. Odds are it has 3:73 gears without limited slip.

Replacing the pinion and other things that you might need to do on the rear end is usually best for a pro, unless you want to learn and have the setup to do it. Other than that I think that I would just find a used rear end with the correct gear ratio.

 

[klhansen]

Used rear axles are a dime a dozen at wrecking yards. It should be pretty easy to find one of the right ratio. An axle assembly and new u-bolts and you have it done. No messing around with setting up gear lash and pattern that are required when replacing R&P.