Diff problems.

[Gunamonkey]

I have a 3903 brushless upgrade with the mm2 running 2s lipos. About every week I am breaking one of the two bearings in the rear diff. What is causing this to happen. It has gotten to he pont that I carry 2 extra diffs so when I'm in the field and it breaks I can replace them. Please post your advice on y this is happening .

[Wolfslash16]

Are you running in dirt/sand? If so, the dirt might be getting into the bearing making them go bad really quick.

[Gunamonkey]

Lately 60/20/20 (sand/dirt/gravel)

[Wolfslash16]

Lately 60/20/20 (sand/dirt/gravel)

Hmmm, my bet is all that sand driving is what killed that bearing. Do you have a picture of the bad bearings?

[Gunamonkey]

Not much to take a picture of . All that's usually left is he outside and inside rings

[Wolfslash16]

Ok, I would also try some better bearings.

Try these threads.

http://traxxas.com/forums/showthread...ring-questions

http://traxxas.com/forums/showthread...light=bearings

[trax de max]

If your breaking bearings every week, there is something not fitting correctly/ seals missing, or it's been sprayed with wd40.

[Gunamonkey]

Ok what do u recommend using to grease the bearings

[trax de max]

I just use lithium bearing grease from the local cycle shop, Left overs from when i do the bike's bearings.
The original WD40 is a grease eater and not a lubricant. If you use this then you'll need to clean up the insides and use a grease afterwards.
Although WD40 is a brand name there is many products under their belt, some lubricants, greases, rust eaters, de-greasers and more.

[trax de max]

I forgot to add, the cycle bearing lithium grease is a lot more viscious, than what automotive lithium grease is.

[Wolfslash16]

I use either marine grease if I run in wet places, or for dry/on road use I use 3 in 1 oil.

[trax de max]

Is it not a bit time consuming changing bearings to run depending on if it's wet or dry conditions.

[Wolfslash16]

Is it not a bit time consuming changing bearings to run depending on if it's wet or dry conditions.

Ha ha ya, but that's not what I do... What I should have said is I use marine grease in the winter so I can drive in snow, and then I use 3 in 1 oil in the summer when I don't get my cars wet.

[trax de max]

After i posted i figured that's what you do, In England we'll be swapping every day.

[trax de max]

Is the problem resolved now gunamonkey.

[EMAXXBRUSHLESS]

If you want to spend more time playing and less time replacing diffs get some 1/8th scale diffs. and get rid of the problem. The little 6x12 bearings don't hold up very good imo.

[fish240]

I just use lithium bearing grease from the local cycle shop, Left overs from when i do the bike's bearings.
The original WD40 is a grease eater and not a lubricant. If you use this then you'll need to clean up the insides and use a grease afterwards.
Although WD40 is a brand name there is many products under their belt, some lubricants, greases, rust eaters, de-greasers and more.

Will the lithium grease work in the tranny as well?

[trax de max]

I don't put none in there. I just let that run as it is.
I only grease the bearings and replace diff/shock fluids if it starts to not look right while driving.
some greases eat plastic and makes it soft and moveable.

[Gunamonkey]

Haven't broke a bearing since but I did destroy a diff last weekend. Wen I opened up the diff the drive gear was cracked,diff cup stripped, and all the Spyder gears destroyed. I was only running 4s. Luckily I had a raplacement diff to through in.

-EMAXXBRUSHLESS
Where can I find a 1/8 scale diff to fit in the stock bulkheads. Or a diff bulkhead set, that replaces all of that

[trax de max]

It may of been weakened buy the bearing damage from previous runs, Hopefully when this is fixed it should last a lot longer. You can get metal diff carriers from flm I think.

[Gunamonkey]

Not from the bearing damage because i completely replaced the diff after the bearings because I didn't want to have to deal with damage from breaking a bearing.

[trax de max]

Do you shim the diffs

[buzzsaw 46]

Haven't broke a bearing since but I did destroy a diff last weekend. Wen I opened up the diff the drive gear was cracked,diff cup stripped, and all the Spyder gears destroyed. I was only running 4s. Luckily I had a raplacement diff to through in.

-EMAXXBRUSHLESS
Where can I find a 1/8 scale diff to fit in the stock bulkheads. Or a diff bulkhead set, that replaces all of that

http://www.fastlanemachine.net/prodd...LM17750&cat=15

http://www.fastlanemachine.net/prodd...LM18750&cat=15

I have been using the FLM Hybrids for years in both my BB T and Brushless E. Good stuff, haven't had a diff issue since.

[Gunamonkey]

No I don't shim the diffs

[trax de max]

I think alot of people have put shims in the diffs and that helped them out. There is a decent write up about it on here somewhere.