BicketyBam

Took the Savage X out today to run in a dirt parking lot and something just didn't seem right. First, there was the sound. It sound like little pebbles bouncing off of metal. I thought maybe it was the rocks in the parking lot, but I wasn't sure. Next I notice that the truck just wasn't getting up to speed. It was shifting into 2nd, but the top end was worse than normal. Finally, I went to go up a mound of frozen snow and notice that only the front tires were spinning trying to get traction. The rears did nothing. I picked the truck up and gassed it and all 4 tires spun. But when I put the rears on the ground and I gassed it, only the front one's spun and the rear made that strange grinding sound. The shaft going from the tranny to the rear diff was spinning - just the tires weren't. So I packed up my crap and headed home. I have disassembled the rear end to this point:



All of the teeth are on the main gear as well as the little one. But when I try to spin it my hand it feel "crunchy" - nothing like the font which feels smooth. What do I do next? I don;t know how to take it apart further or what I am even looking for at this point. Can someone please point me in the right direction?

BicketyBam

OK - I got he diff out. Here are some pictures:






The diff feels smooth when I turn the cups - no grinding or binding.

When I turn this though, it feels like something is binding:



Should I be looking at the tranny?

Van Pelt

looks like you need to buy the items listed below. You probably crunched the bevel gears. This is a very good way to build a solid diff. In my X RTR, I bought the more expensive aluminum diff and then did all the shimming myself. Never had another problem. Now that X RTR is my son's and he beats it and it takes it. My X SS diffs are rock solid and have never given me trouble... I beat this thing also...

Diff cup and shims: http://www2.towerhobbies.com/cgi-bin...27&FVPROFIL=++
Bevel gears: http://www2.towerhobbies.com/cgi-bin...93&FVPROFIL=++

You'll need everything X2 if you want to do the front also.

Just my thoughts... Pull the differential apart and you'll see that maybe one side gear is chewed up. Doesn't take much because of all the clearance that if came with from the factory.

Jon.

Fltlander

BicketyBam,
This is just my 2 cents worth. When did you put the dual brakes on? I was just finishing up on bulletproofing my truck and there was a binding in my transmission just to find out it was the dual brakes binding.Might want to check them out.Also have you shimmed your diffs?

Van Pelt

for your questions, "Should I be looking at the tranny"... my answer would be check the differential gears first. The trans is solid (front to rear) power output. So, if the front is turning, then rear will also IF the allen screw is stil in the cup joint. Check those also.

there are 2 sizes:
http://www2.towerhobbies.com/cgi-bin...?&I=LXDLG8&P=7
http://www2.towerhobbies.com/cgi-bin...95&FVPROFIL=++

BicketyBam

How about this. Look where the tip of the screwdriver is. The groove where the bearing sits on that side is really worn down compared to the other. Will that cause a problem? It's hard to see.



BTW - I didn't shim a thing and the tranny looks good. I am going to pull the diff apart next.

losidriver09

ok i have a question how come they make the bottom of the diff wide open and how come it isnt a sealed differential , so many rocks and other debris gets in there and causes problems , how do u fix it ?

BicketyBam

Hey - check this out. Is this bearing just supposed slide around like this?

Fltlander

The stock diff cases flex alot...sounds like a shimming job on the way...
losidriver09>I seal it with RTV..The bottom of the diff case,the alum. plate and the skid plate...good waterproofing and keeps the dirt out.

BicketyBam

That has to be the problem. That B085 bearing is toast.

Fltlander

I go with Boca bearing...alittle expensive but worth it. http://www.bocabearings.com/main1.as...59&n=*20-150GS

BicketyBam

I only need one - do I need to buy $100 worth?

Fltlander

http://www.bocabearings.com/main1.as...93&n=MR688-2GS

madmouse

it looks like u took a few teeth off the pin gear the small one.

if ur diff cups turn and feel smoth when u r holding the ring gear then u spiders r ok.
as for the bearing yes it is sop. to come off of the cup.

take the pin gear out and clean it up and post some more pics of it please if u could so i can get a better look at it.

as for rebulding the diffs. u dont need the xss stuff!!!! everyone on here thinks u do but u dont.
what u need is 4 gear diffs shimed and u will be fine (even without having the alum diff cups) the only diff from the xss stuff and the reg x is the cup. as for shims get the hellfire shims, put one on each side of the bearing (behind the out drive cup) put some 7-10k diff oil in the diffs and put some lub on the ring and pin gears when u get it all set back and u will be good to go.

and before anyone says anything about that diff set up i have something to let yall know.

i have been riping teeth off of my pins for a long time (thanks to my axial) and the last time i did, one of my friends helped me with it, i got new x bulks and some hellfire shims. after breaking in the diffs i have been giving them a fit, and for the 1st time they r holding and i bent my 1st dog bone sat ( before my diffs were the weak link now its the bones ) i know that my motor has way more power then a stocker and if mine r holding up then it will work for u to.

Fltlander

Seems like they're having alittle problem with their site. I would at least get 2 or 4 for both diffs.

fxrs

If that bearing is bad and the bulkhead is worn
were you are pointing with the screw driver, the
the diff will push away from the pinion gear.
you'll need to replace that bulkhead and check the
pinion gear also.

BicketyBam

This gear looks good to me.



It may be sop for the bearing to move, but what's left can't even be called a bearing. It's the metal outside of it. The rest is toast. I will take it off and show you.

burnchassis3

If your B085 bearing is toast,That causes play in the ring ,and pinoin gear..if the pinoin is ok,the ring may be worn out
OR
You may be lucky as the bearing went causing play.... not letting the teeth mesh enough to grind or break off.
New B085 ,diff case,and bulkhead are a must....not including whatever if anything that may be bad in the diff itself.
DEFINATELY Pull the 4 screws out of it and check it before you put it back together.
CS

BicketyBam

here is the bearing, or what's left of it.



I just put it on to show that there is nothing left to it:



The gears on the inside looked ok.

BicketyBam

I think it is as you said. Bearing went, causing play and wear to the gearbox/bulkhead. I am going to order a B085 and part number 85235. Then I will pray I can remember how to get it back together.

The small bevel gears on the inside (87193a and 87193b) looked good and they mesh fine.

Talk about getting a crash course in taking these things apart. My next truck will definitely be one I have to assemble.

fxrs

Just to let you know, I had one of those go bad in my sons savage
about a year and half ago. He had gotten dead grass and some weeds
wrapped around the drive cup. That whole mess along with dirt and
sand from the track he races at wiped out the rubber seal on the bearing.
But I found the bad bearing while changing the diff fluid so no
real damage was done. I now have spares of all the bearings in a savage.

madmouse

ya i would say the bearing is the prob.

i would check over all the diff bearings and go from there.

losidriver09

while we are on the topic of differentials i hope you guys dont mind explaing or showing a hwo to tune the diffs section , im wanting to get into racing this year and i woudlnt mind a how to section to read on , i just dont understand if you put diff fluid in the diff and it is not sealed woudlnt it just get all over the place , i have seen sealed diffs but are there none for the savage and if there are can soemone show me a good differential section ?

CWC

This just happened to me so I going to avid.com $1 bearings so I'm replacing all the bearings bulkheads and diffcups.

topdollr

what is the best way to get the bearing back on? Mine had the same problem and now that I have the new bearings I thought I could press them on with a C clamp but that turns out harder then said. Any tips or trick would greatly be appreciated.

thanks in advance.