Diamond Drive Bearing Failure Repair Write Up - How to...

[kevin]

Good to know , because i havnt ordered any bearings since last fall when BDX was running that single row bearing in there bearing kits , even for the 05/06 sleds that left the factory with the double row - I sent Hatch an message a few days back - I said pick your poison , China or Japan

The open caged bearings that get oil are not the issue (Never with any of mine anyways) unless of course you run it out of oil - Its these sealed bearings , the one behind your secondary on the input shaft , and then of course this whole single row/double row mess[/b]

Exactly. At least we know what to look for

[killerrf]

as i was reading and posts from snowest on this topic... if you cant bolt it right back up without having to loosen anything else like the driveshaft bolt... i would say that the big bearing is going to fail faster than the original. something is not right if you can just bolt it back up. thats my opinion. you can see from silverram's pics that the shaft protruded above the old bearing and shims. after he installed the new wider bearing there is no more shaft showing... probably flush. if i were you silverram i would maybe take that apart and trim that drive shaft some. i might check mine this year but when i do i think a better quality single row bearing might be all that is needed. especially if this double row isnt going to fit properly. by measuring the shims and single row bearing then comparing the double wide size will give you an idea if it fits or not.

[johnmaster]

Never realized what a big deal this is. We had an 08 M with roughly 4000 miles wreck that bearing, the bearing parts basically ate all the gears and wrecked the entire DD except for the case. They are $1400 retail!!! That one now has an 09 non-reverse box in there we found until we can find a good used one with reverse for cheap.
Had a friend with an 07 CF (basically the same DD) with about 4000 miles on it when he cracked the case in an accident and needed it welded up. After seeing the blown up one he decided to put new bearings in it while it was apart. The same bearing was probably one trip away from doing the same thing as the M. Seal was shot and pushed out and parts of the cage were falling out on the bench. Peer made in china from the factory and peer made in china from BDX in their kit, which was actually a nice kit. Personally I wouldnt take your sled past 4000 miles without changing this bearing. I think I am going to find a japanese replacement single row bearing, hoping the cage will hold together longer than the OEM peer type.

[dvt520]

Just bought a 09 CF8 with 2k miles. Removed DD and inspected bearing. Still intact but you could tell it was a little loose inside. Also the OD of bearing had chater marks. Probable thin bearing cannot take abuse of planetary. I have checked clearance of 5203 bearing when putting cover back on and their is zero clearance. 6203 has about .016" clearance which is about the same as you measure thin bearing and spacer with wide bearing.

Any one using 5203 bearing should surface grind each side equal to get clearance. I am grinding .007" off each side and should be in ball park.

[schnid21]

When you say surface grind both sides, what exactly are you grinding. I only have 1000 miles on mine so far but thinking this might be some good PM to do before winter starts.

[troyburt]

[quote]
When you say surface grind both sides, what exactly are you grinding. I only have 1000 miles on mine so far but thinking this might be some good PM to do before winter starts.
[/quote/]

i'm 95% sure your bearing will be toast, just take the dd out of the sled and replace with 5203. mine fit good.

[dvt520]

Taking .007" off both sides of (I.D. and O.D. race) will come close to seal but will not touch it. You might be alright with no modification but when I measured mine their was no play when I assembled everything, so just to be safe I made sure the clearance was close to orginal.

[dvt520]

Taking .007" off both sides of (I.D. and O.D. race) will come close to seal but will not touch it. You might be alright with no modification but when I measured mine their was no play when I assembled everything, so just to be safe I made sure the clearance was close to orginal.

[schnid21]

Based on what I have learned so far from mine.

I pulled the DD out. Way easier than working on it in the sled. I removed the DD cover. Bearing was in good shape but rather than risk a catastrophic failure next season I did the following:

Using a piece of solder, I laid it on top of the smaller open bearing and then reinstalled the case and torqued the bolts down. Then I removed the cover again and measured the thickness of the solder where it got squished. Came up with .96mm. Then I removed the bearing and spacer. They measure out at 17.1mm on my sled. Based on a 5203-2RS having a width of 17.5mm I should have no problem fitting the bearing in.

But just to be on the safe side, I am going to remove .4mm from the shaft where the bearing sits. This will ensure that there is the same amount of clearance as before, and the teeth of the gears are properly lined up. Not machining the shaft would actually offset the gear teeth by whatever difference you measure between the 6203 w/spacer and the 5203 bearing. Chances are this would not make a difference, but for a couple minutes on a lathe its a pretty easy fix.

Once all that is done, I will go through the rest of the procedure the guys on Snowest talk about with regards to making sure the DD bolts flush with the tunnel. There is a post on that website with about 300 replies on this issue. Some guys have done some pretty in depth research into this issue.

As for grinding I realize its only .007" you are going to take off, but with all the angular misalignment issues with the DD I would think you would want as much bearing wall as possible to take the loads?

[witewtr201]

i have a 07 xfire 8 and i am going to upgrade my track to a 2''. I am going to get the dd fluid changed while its out. would anyone recommend the bearing being replaced since the dds out?....ooo yeah sled has 2800 miles on it