Xoutpost.com - X3 Transfer case HELP!!!

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Maybe I should have mentioned that I use some equipment to make that difference visible. With the naked eye you cannot see it.

Let's see, for most X5 wheel/tire combos, the wheel diameter is about 74 cm. Radius is therefore 37cm. 3% of 37 is 1.1cm just under 1/2". (Since the circumference is pi * diam the 3% is linear.)

The typo is not that far off for the X5 tho and not too bad for the X3 either. In inches 29"*3.14*3% ~= 2.7 inches. So about 3" is not too far from 3%. IIRC, the tire for an X3 is 27 inches", that would make the delta for circumference about 2.5 inches.

Quote:

Originally Posted by JCL (Post 782928)

Which part isn't clear? Anything beyond approximately 3" [EDIT - 3%] difference in rolling diameter front/rear stresses the transfer case and risks damage. With a pre-2004 X5 solid transfer case that shows up in problems with the splines. With an x-drive transfer case in either an X3 or X5 that shows up in wear to the clutch packs. Different manufacturers of tires have variations in actual rolling diameter, which is why many tire stores will want to replace your tires four at a time, not two at a time, so you don't come back and blame them if you have problems with a transfer case later.

I understand the difference in tire diameter can and will impose stresses on the transfer case internals, but the post in which I am questioning is that the front and rear tires were the proper size tires. If the manufacture of these tires produces the front and rear tires a 1/2 inch bigger respectively, then the OEM size, there should be no stress on the transfer case. Based on the thread to which I replied WHAT?, the question remains.

Quote:

Originally Posted by THK (Post 782949)

I agree, if the replacement tires were all from the same manufacturer. Since the poster referenced tires from different manufacturers being different sizes, I read it as him having different brands of tires front and rear.

Quote:

Originally Posted by JCL (Post 782953)

We do agree with each other, :high5: I was taking the tire diameter difference as all 4 were not the same diameter as OEM.

Have a good evening!

Sorry Guys I disappeared. Yes I had fixed my transfer case and it is running just fine so far (10k miles, some in rough winter conditions). Had a bearing replased with a different closed one (also thicker). Had cut away the damaged surfases. Was not able to find parts anywhere in the world.

Quote:

Originally Posted by nikitich (Post 795731)

do you have any pics available? did u have only that mechanical problem or did u have anything esle. Actuator motor and its mechanical cams?

no just the mechanical problem. There was the whyning sound from other bearings and that was the reason why I took the transfer case apart. I guess that usually the shown bearing falls apart and damages the transfer case. I think that the reason is insufficient amount of oil because it is lubricated by drops of oil carried up by the chain.

Are you talking about the transfer case ATC400? Did you notice any damage to the teflon/plastic mechanism from the actuator electric motor to the leverage inside the TC?

E-mail this company they are located in South Carolina USA, maybe they can direct you to their part supplier

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