Explain Bearing Differences Please....

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OK, here's the deal. I'm looking at my John Deere 360 disc. According to Deere's parts list, there are 2 styles of bearings that can be used for the gangs.The older style (which I currently have) is Deere # B34215.I've found it crossed to the following: GW211PPB9, DS211TTR9, 1AC11.The specs I've found are: 2 3/16" ID round (although I've seen some of the cross-refs anywhere from 2.185" - 2.195"), 100mm OD.The best pictures I've found are:1) http://www.noc.ua/en/online-catalog-...16D1V1&key=8732) http://www.thebigbearingstore.com/se...V1-DISC/DetailNow, although this bearing is still available, they don't last very long. I'm guessing due to the extreme side load on a ball-bearing due to the cutting action of the discs, but that's just a theory. Apparently there was a update way-back-when. It would involve changing the flanged plates that holds the bearing, but that's only about $35 so could pay for itself pretty quick if it works.The new bearing is Deere #AA28186. Cross-refs to GW211PPB20. For info, Deere kit #AA30942 contains the bearing, flanges, gasket, grease fitting, bolts - basically everything needed to change over to the new system.Specs of course are very similar (especially the ID!) The problem is I can't find a cross-section of the bearing to see what the difference is.I found these pics:1) http://www.thebigbearingstore.com/se...ly-from/Detail2) http://www.thebigbearingstore.com/se...re-Disc/DetailCan anyone tell what the difference is between these 2 bearings? The local dealer doesn't have the new one in stock so I can't compare to my current bearings.AndrewP.S.For those unfamiliar with discs, you'll notice no setscrews, locking collars, etc. to lock the bearing to the shaft. That's because the disc blades, spacers, bearings, etc. are all held together with a gang-bolt. On this particular disc it is 1 1/4" square, 1 1/4" nuts on the ends. You put a wrench on one nut and brace to the frame. Put a wrench with a LONG cheater pipe (I use 8 feet) on the other end and start jumping to loosen or tighten - I am so looking forward to doing this on 8 gangs.If you think that's extreme, our big Rome Breaking Disc uses a 2 3/16" gang bolt. The nuts take about a 4 inch wrench. We use 48" pipe wrenches and either 12+ feet of cheater bar, or pull on them with a small tractor!
Reply:The originals mention deep-groove, Y-bearing, single row. I understand deep-groove and single row, but what's Y-bearing???AndrewLast edited by Andrew_D; 09-29-2011 at 10:31 PM.
Reply:Hi Andrew, I just went through the same deal on a 336 jd hay baler, i bought separate bearings and flanges to replace the riveted style that were on the machine, the bearings were about .075 thicker but they had to be shimmed anyway for the pickup reel, and the cost was about 75% less than buying from JD, here is a link to where i bought them, they do show dimensions on the siteTimhttp://www.shoupparts.com
Reply:Some more pics from TimT's link...The older bearing: http://www.shoupparts.com/DS211-TTR9/The newer bearing: http://www.shoupparts.com/SH38637/Why is it that I can find cut-away views of the old one but not the new one....grrrrr....Andrew
Reply:Ball bearings are designed for radial loads.  If you want a ball bearing to take greater axial loads the race has to have a deeper groove to take the side load.  Some ball bearings even have the shoulder deeper on only one side and are designed for axial thrust in one direction.   You might try a bearing manufacturer website and download their catalogue.  OEMs love to spec their own bearing part number but in the end most bearings are a standard catalogue item.  I helped replace a rear bearing in a Pierce Arrow roadster.  I was amazed to find the number on this bearing and race from 190something was still in the SKF catalogue.  And oh yes don't put your ground in a location where welding current goes through bearings,,, it seems obvious but it is done all the timeLast edited by lotechman; 09-30-2011 at 01:51 PM.
Reply:the difference if they are calling the bearings correctly are, the old bearing uses steel balls and the new bearing uses roller s or small metal cylinders, just like the front beearings of a car, the roller bearings have much more surface area than a ball bearing and take side loads better..Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:Originally Posted by roadkillbobbthe difference if they are calling the bearings correctly are, the old bearing uses steel balls and the new bearing uses roller s or small metal cylinders, just like the front beearings of a car, the roller bearings have much more surface area than a ball bearing and take side loads better..
Reply:Originally Posted by lotechmanBall bearings are designed for radial loads.  If you want a ball bearing to take greater axial loads the race has to have a deeper groove to take the side load.  Some ball bearings even have the shoulder deeper on only one side and are designed for axial thrust in one direction.
Reply:Ball bearings are used for both radial and axial loads in both directions.It's in the design of the races and depth of the grooves.Semper FiJesus may have been a Carpenter, but his dad was a Millwright" A grinder and a can of paint, will make a welder what he aint' "I've done so much, with so little, for so long, that now I can do anything with nothing!
Reply:Hi Andrew, my bearing interchange manuals are pretty dated... But I'm pretty sure the difference is more about the seals and tolerance changes and possibly very small differences in the bearing groove ground in the races. The ID, OD and widths stay pretty much the same. You would have to contact a factory rep to find out the load differences if any on bearing load ratings when there are number changes.Below is a link to the Timken/Fafnir AG interchange PDF which covers about everything they make for AG stuff.http://www.ducasse.cl/common/asp/pag...gArchivoId=970Also I attached a couple of scans from my 20+ year old bearing manual Vol. 1. showing the bearing types for AG disk use. A counter man at any bearing house will be able to cross numbers at their tube on the fly.Good LuckMatt Attached Images
Reply:The style of holder is similar to the second picture in Matt's attachment - two flanges surround the bearing and bolt to the vertical support.There's seems to be lots of info out there about the original bearings, but little on the newer style....Andrew
Reply:After a little search found a site with the bearing specs. Apparently the outer race of the new style is quite a bit wider and has an unusual seal.Bearing PageFirst time putting in a link - let's see if it works.
Reply:If I remember correctly from 15 years ago when we changed ours out the newer bearing had a seal that wouldn't allow dirt and moisture to enter it as easily as the old.  There were some other changes but I don't remember what they were.  We bought the kit and everything changed pretty much across. 48' pipewrench 16' cheater pipe, 230# person jumping on end of cheater. ( didn't have a small tractor)