Factory diff bearings not same as new bearings....
Discussion
I'm rebuilding my axles to fit locking diffs on my Vitara. I've got new bearings of the same bearing number in this case bearing model 30307. Comparing the original Koyo 30307 bearing with the new CFG 30307 bearing the external dimensions are exactly the same and the bearing fits, but the angle of the needle rollers and tapered bearing race is different to the original bearings.
I had the same happen last time I rebuilt a Vitara diff, that time using Timken 30307 bearing, and the same scenario was present. The bearing fitted, all worked, but the angle of the race and rollers was not the same.
I spoke to Timken that time who said that the original bearings have no right to be different because the bearing is specified by the bearing number and that all manufacturers follow the same dimensions.
Only thing I can think of is that Suzuki have done something non standard, using a bearing race angle closer to 45 degrees to better distribute the perpendicular forces in a diff.
I had the same happen last time I rebuilt a Vitara diff, that time using Timken 30307 bearing, and the same scenario was present. The bearing fitted, all worked, but the angle of the race and rollers was not the same.
I spoke to Timken that time who said that the original bearings have no right to be different because the bearing is specified by the bearing number and that all manufacturers follow the same dimensions.
Only thing I can think of is that Suzuki have done something non standard, using a bearing race angle closer to 45 degrees to better distribute the perpendicular forces in a diff.
It's not uncommon for there to be different levels of part which are interchangeable, usually differentiated by a suffix on the end of the full part number.
Perhaps they had a durability or noise issue with that bearing and they changed the race angle during production? If the bearing is numbered and sold as a whole unit rather than as parts then it's possible you've got an earlier component that was fitted to your vehicle originally that was later updated to the one you have.
Perhaps they had a durability or noise issue with that bearing and they changed the race angle during production? If the bearing is numbered and sold as a whole unit rather than as parts then it's possible you've got an earlier component that was fitted to your vehicle originally that was later updated to the one you have.
I did notice that there's a suffix at the end which differs among bearing manufacturers. Eg Timken 30307XXX, or Fag 30307YYY. But I'd read that this suffix is just some internal manufacturers code, and to be ignored. Yeah I probably read that on the internet somewhere so may be incorrect.
Ok I will use this bearing with the wrong race angle for this diff, as it's the front diff on a part-time 4x4 so it only sees a few dozen miles per year, and I have the race to match the new angle. I haven't ordered bearings for my rear diff yet, and when I do I will get the exact same manufacturer and suffix bearing.
Ok I will use this bearing with the wrong race angle for this diff, as it's the front diff on a part-time 4x4 so it only sees a few dozen miles per year, and I have the race to match the new angle. I haven't ordered bearings for my rear diff yet, and when I do I will get the exact same manufacturer and suffix bearing.
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