J
So if I choose to run the 5203, is it determined that a sealed bearing is still the way to go or should I opt for the open design assuming it's getting enough lubrication from the oil in the case?
2011 Diamond Drive bearing?
- Thread starter Farmington Motorsports #9
- Start date
F
I swapped out my 6203 this weekend with a 4203. I had about .060 of the end of the shaft exposed with the 6203 and the spacer, and once I removed both of them and installed the 4203 I had within .005 of the original measurement for the exposed shaft.
I had about 280 miles on my sled and my fluid and bearings looked fine, but I guess it is better to be safe than sorry.
Thanks for eveyone's responses.
I had about 280 miles on my sled and my fluid and bearings looked fine, but I guess it is better to be safe than sorry.
Thanks for eveyone's responses.
09-11 DD failures
Because of posts like this......
We have pulled down quite a few DD's this fall. Every 6203 bearing from 50 to 800 miles on it has lost the cage holding the ball bearings.
After measuring the first DD (2010) because the cover "rocked a little" during assembly with the gasket on....I pulled it back off and found that the housing measures up very closely to working with a 5203 replacment upgrade but didn't on this particular drive. (I also checked the output shaft to make sure it was all the way in the housing) So....if you meausre the engagement of the sun gear to the planetary gears...which should be right on....I've had to lengthen the bearing journal around .060" to offset the bearing replacment difference from original to make the gears mesh dead on. Not saying all DD's will be this way....when in doubt....measure. Then measure again to be sure before machining anything. Most of the information I have learned from BD and AC is they don't need to machine anything. I found out differently.
On the 09-11's we have done....they all have had to be machined to make the sun/planets align true to each other - and/or machining so the cover will fit back on and not preload the bearings on the driven side of the gearbox. (taking them out in a very short time)
There is a ton of information on this floating around and I thank everyone that has posted comments on Snowest. It makes it easier to digg into something and figure it out when you know what you are looking for.
Because of posts like this......
We have pulled down quite a few DD's this fall. Every 6203 bearing from 50 to 800 miles on it has lost the cage holding the ball bearings.
After measuring the first DD (2010) because the cover "rocked a little" during assembly with the gasket on....I pulled it back off and found that the housing measures up very closely to working with a 5203 replacment upgrade but didn't on this particular drive. (I also checked the output shaft to make sure it was all the way in the housing) So....if you meausre the engagement of the sun gear to the planetary gears...which should be right on....I've had to lengthen the bearing journal around .060" to offset the bearing replacment difference from original to make the gears mesh dead on. Not saying all DD's will be this way....when in doubt....measure. Then measure again to be sure before machining anything. Most of the information I have learned from BD and AC is they don't need to machine anything. I found out differently.
On the 09-11's we have done....they all have had to be machined to make the sun/planets align true to each other - and/or machining so the cover will fit back on and not preload the bearings on the driven side of the gearbox. (taking them out in a very short time)
There is a ton of information on this floating around and I thank everyone that has posted comments on Snowest. It makes it easier to digg into something and figure it out when you know what you are looking for.
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F
After the first DD oil change on my new M8 2011, i replaced AC oil by an other brand synthetic oil.This year, just doing the 5203 to prevent future nightmare, flushed the oil and still look like new.:noidea:
Also, the bearing's guy told me that the 5203 with C3 at the end of the number is rated to 1800RPM & plus, with more clearance.It's my first time bearing change so whish me luck!!!:face-icon-small-win
Also, the bearing's guy told me that the 5203 with C3 at the end of the number is rated to 1800RPM & plus, with more clearance.It's my first time bearing change so whish me luck!!!:face-icon-small-win
J
So has anyone figured out what oil AC is using? Appears to be a standard 10wt.
A
my 2010 has been running the 5203 bearing since 400 miles when my stock one started showing signs of failing. i have 2k miles on it now.
been great for 1600 miles. i tore it apart at the end of last season and it was still in great condition.
BDX bearing, guess i was one of the ones that got lucky and it just fit...
-Aksnopro
been great for 1600 miles. i tore it apart at the end of last season and it was still in great condition.
BDX bearing, guess i was one of the ones that got lucky and it just fit...
-Aksnopro
S
Never mind now I see which one it is... Can you see it good enough if you pull the cover or does that shaft with the bearing on it just come out easy? Thanks.
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J
2011 Diamond Drive
Spoke extensively with Jeff at BDX regarding the shaving of the drive shaft.
He has replaced 100 or so bearings without ever shaving the shaft, claims it is a non-issue.
The key to proper install is to pull the Diamond Drive off the machine, replace spacer and faulty bearing and re-seat cover and torque according to AC specs. Jeff says problems occur when you try to replace bearing and recover WITHOUT removing the DD drive. The cover will not seat properly and cause faulty drive shaft and bearing function.
The reason I am posting is there are 5 plus DD bearing posts and there seems to be no definitive answers. Isn't BDX the original designer of the DD? Don't they work on them extensively? Wouldn't they be the best resource for this? That said I am still nervous about mucking with my brand new 2011 M8 while under warranty.:face-icon-small-win
Spoke extensively with Jeff at BDX regarding the shaving of the drive shaft.
He has replaced 100 or so bearings without ever shaving the shaft, claims it is a non-issue.
The key to proper install is to pull the Diamond Drive off the machine, replace spacer and faulty bearing and re-seat cover and torque according to AC specs. Jeff says problems occur when you try to replace bearing and recover WITHOUT removing the DD drive. The cover will not seat properly and cause faulty drive shaft and bearing function.
The reason I am posting is there are 5 plus DD bearing posts and there seems to be no definitive answers. Isn't BDX the original designer of the DD? Don't they work on them extensively? Wouldn't they be the best resource for this? That said I am still nervous about mucking with my brand new 2011 M8 while under warranty.:face-icon-small-win
K
I hear ya and BDX would be far more knowlegeable than I. I would say they were the original designers but are not in charge of current manufacturing quality control. I took measurements with a digital caliper and straight edge and can guarantee you that without knocking a few thousands off the shoulder of the shaft that the wider bearing would be in contact with the case with the cover tightened down regardless of whether or not it was in the machine. I did take all my measurements with the DD on the bench so the mounting bolts were not twisting or putting any other pressure on the case.
Each to their own though. My sled is still under factory warranty but that wouldn't have done anything for me back in the boonies and the bearing in mine was shot at 400 miles. When I say shot I don't mean getting rough I mean seals gone and balls getting crunched up in the gears. I had to take the entire drive apart to get all the shrapnel out.
Each to their own though. My sled is still under factory warranty but that wouldn't have done anything for me back in the boonies and the bearing in mine was shot at 400 miles. When I say shot I don't mean getting rough I mean seals gone and balls getting crunched up in the gears. I had to take the entire drive apart to get all the shrapnel out.
I totally agree with you on a warranty sled to go with the warranty. I spoke to BDX too. I learned that they designed the original DD. Cat took it "in house" after a couple years into it. Therefore we are back to the factory for answers and design changes they made.
Most dealers I have spoke with don't really care to modify factory parts to work. I agree with that too....you shouldn't have to.
Mountains are starting to get a little snow......IT'S COMING!!!! CAN'T WAIT!!!!
A
you cant argue with works, mine installed on a bench has worked flawlessly and looks great at 1600 miles...
Well here is my answer. 2011 M8 with 345 miles and this was all that was left. I did check and measure everything out and I had to cut .057 off the shoulder of the shaft to bring everything back to OEM specs. Nice.....
K
Exactly what the bearing out of my 2010 with 433 miles looked like!
D
If you can find a 4203 it will be an exact fit for the factory bearing and spacer. Rear wheel bearing for a Norton Commando!
J
Thanks for the advice. I will be measuring when I do my bearing exchange shortly because of posts like yours.:face-icon-small-win
Makes you think about the crappy quality control AC must have if they can get such a variety of variances on one issue. You'd think it would be one problem consistently one way or another.
Makes you think about the crappy quality control AC must have if they can get such a variety of variances on one issue. You'd think it would be one problem consistently one way or another.
K
No problem. :face-icon-small-coo
5203 Bearing
I have had a couple people ask where to pick up the 5203 bearing. Any seal/bearing house should be able to get the "PEER" brand name 5203 sealed bearing. There are a lot of auto parts places that either have or can order these as well. Other brand names like NTN, SKF ect will aslo work because the 5203 is an industry standard for size and spec on loads and speeds.
Just a heads up.
I have had a couple people ask where to pick up the 5203 bearing. Any seal/bearing house should be able to get the "PEER" brand name 5203 sealed bearing. There are a lot of auto parts places that either have or can order these as well. Other brand names like NTN, SKF ect will aslo work because the 5203 is an industry standard for size and spec on loads and speeds.
Just a heads up.
I took apart my DD on a 2010 M8 with 1.4k on it. Bearing was definitely shot and the 5203 from BDX certainly did not seat on the shaft as far as the stock bearing. I did machine it down until it did. I don't remember exactly but I think it was only 0.02". I didn't remove the assembly from the sled, just did it from the side. The cover did rock a little bit but with some nudging and a good criss cross pattern tightening the cover bolts, it did 'snap' into place. I think the only reason it did that was because the tolerance between the bearings and the circular seats on the cover and backplate were giving a little resistance....not because the new replacement bearing wasn't seating. Cover was cold too.
I lifted the track, spun it and had someone else spin it while I felt the secondary shaft and nothing was binding.
I beleive the guys at BDX are getting them to seat without machining the shaft. If you look at where that bearing seats, it's not a precise little cavern.....it's longer than the bearing. I just wasn't comfortable having the bearing sit beyond the end of the shaft so I shaved the shoulder down. They MAY actually be pressing the bearing further on the shaft when they assemble it.
I lifted the track, spun it and had someone else spin it while I felt the secondary shaft and nothing was binding.
I beleive the guys at BDX are getting them to seat without machining the shaft. If you look at where that bearing seats, it's not a precise little cavern.....it's longer than the bearing. I just wasn't comfortable having the bearing sit beyond the end of the shaft so I shaved the shoulder down. They MAY actually be pressing the bearing further on the shaft when they assemble it.
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D
14k miles? All of a sudden the deal you got on that sled doesn't seem so good. 
