Differential binding with wheels turned

[IonicRipper]

I disassembled my SCX10's front diff for maintenance but after reassembling it, I noticed some sort of binding when giving it some throttle. Took it all apart and reassembled again fixed the problem except when the wheels are turned... The front end shakes like its going to self destruct and there is some sort of grinding noise when the wheels are turned full lock (either direction.) I spent hours trying to figure what I did wrong but cannot find anything. Any suggestions?

[ZippoMan]

Adjust the EPA on the TX. You are steering too far in each direction. That is my opinion. It will do exactly what you said if you push the steering too far left or right.

[IonicRipper]

Problem is I don't remember it doing that before disassembling it...

[6sharky9]

Your driveshafts have alignment marks on them..make sure its correct or it will do somewhat what your describing with with the shaking.

[TacoCrawler]

^ what he said... phase the drive shaft universal joints.

use the alignment marks if they are there.

I'm guessing your steering is too extreme...
and the axle is binding in the cup.

If you have universal axle shafts...
those could also be binding if the steering is too radical.

[IonicRipper]

But the differential shouldn't be affected by steering, being a solid axle, no? There is no change in the driveshaft angle when steering.

Not arguing with you guys, just trying to understand...

[ROLANDROCKSHOP]

Its not a solid axle,its 2 piece housing..so there will be a Lil flex/give.

Your pinion angle good??

[IonicRipper]

Diff or motor pinion?

Or do you mean the differential pinion shaft angle...

I noticed the front diff pinion had a chipped tooth. Could that be causing my problem?

[ROLANDROCKSHOP]

Possibly..

[Natedog]

Originally Posted by TacoCrawler

...

I'm guessing your steering is too extreme...

....If you have universal axle shafts...
those could also be binding if the steering is too radical.

My SCX axles with Axial CVDs, aluminum chubs, and high steer knuckles shakes the whole front axle at full steering lock and lots of throttle. My front end will steer until the 1.9 Ripsaws rub the shocks and lower links...driveshafts are in phase and everything is nice and tight as it gets. However, the vibration starts at about half steering to either side. I think it's because the cvds don't quite properly line up with the steering axis in the knuckles. My Wraith has no such problems using Axial universals and VP aluminum chubs and knuckles.

[TacoCrawler]

Originally Posted by Natedog

My SCX axles with Axial CVDs, aluminum chubs, and high steer knuckles shakes the whole front axle at full steering lock and lots of throttle. My front end will steer until the 1.9 Ripsaws rub the shocks and lower links...driveshafts are in phase and everything is nice and tight as it gets. However, the vibration starts at about half steering to either side. I think it's because the cvds don't quite properly line up with the steering axis in the knuckles. My Wraith has no such problems using Axial universals and VP aluminum chubs and knuckles.

I also have the Axial CVD's and their 8* alloy Chubs/knuckles...
and my junk doesn't seem to be out of balance or have any shake.
My steering links are getting changed tho'
because they do limit the steering throw at the moment.

I did install the drive shafts incorrectly once...
and that created a really bad imbalance issue...
And is very obvious.
but once corrected (phased) the problem was gone.

I also run "beef tubes" in both axles...
can't say they are even noticed...
'cept they make the axle(s) stronger (less flex), adds unsprung weight...
and offers the Chubs something more substantial to thread into.

Are you using the oem WB8 drive shafts or something else ?

Maybe yours shakes at full steer (L/R) lock
'cuz the tires are rubbing on something ?
Or maybe it's just tire scrub ?
Is your Chub/knuckle caster setting acceptable ?

[Natedog]

Originally Posted by TacoCrawler

I also have the Axial CVD's and their 8* alloy Chubs/knuckles...
and my junk doesn't seem to be out of balance or have any shake.
My steering links are getting changed tho'
because they do limit the steering throw at the moment.

I did install the drive shafts incorrectly once...
and that created a really bad imbalance issue...
And is very obvious.
but once corrected (phased) the problem was gone.

I also run "beef tubes" in both axles...
can't say they are even noticed...
'cept they make the axle(s) stronger (less flex), adds unsprung weight...
and offers the Chubs something more substantial to thread into.

Are you using the oem WB8 drive shafts or something else ?

Maybe yours shakes at full steer (L/R) lock
'cuz the tires are rubbing on something ?
Or maybe it's just tire scrub ?
Is your Chub/knuckle caster setting acceptable ?

8*...must be VP chubs or you did the XR mod?

Beef tubes here too.

Yes oem old school (like Traxxas) driveshafts.

Not due to tire rubbing, it starts before that.
My caster is on steeper (leaned back at top) of the two holes (Axial aluminum parts) and the front axle is rolled back a bit for even more caster, so my front driveshaft is kinda steep angle, but it only shakes at sharp steering angle....straight ahead full throttle 3s 45T motor and 20/87 gearing is fine.

[TacoCrawler]

Originally Posted by Natedog

8*...must be VP chubs or you did the XR mod?

No VP or XR stuff on muh junk.

Mine are the Axial alloy 8* Chubs/knuckles.
^ yes, Axial offers those.

* utilized so that I could rotate the axle forward some...
and still have some positive caster.

my problem is the straight steering link hits the axle's center chunk.
and that's even with using the offset Axial link ends.

So a bent rod is on order to hopefully clear better.
Then maybe I'll have an increased steering throw.
...but hopefully not the issue you have !?

Do you use a CMS ? Panhard ?

My steering servo is still mounted to the axle.
Maybe not to scale... but seems to work fine.
I hate to spend more money on something that
might cost more money to make correct.

I'm fairly satisfied with utilizing the 4 link Ft/Rr
and really have no intentions of altering that design.

I'm on a short bus budget...
and spending money on one thing....
usually leads to spending more... in support of changes.
So... unless I can make it from scratch... I do less.

besides... less is more

[Natedog]

Originally Posted by TacoCrawler

No VP or XR stuff on muh junk.

Mine are the Axial alloy 8* Chubs/knuckles.
^ yes, Axial offers those.

* utilized so that I could rotate the axle forward some...
and still have some positive caster.

my problem is the straight steering link hits the axle's center chunk.
and that's even with using the offset Axial link ends.

So a bent rod is on order to hopefully clear better.
Then maybe I'll have an increased steering throw.
...but hopefully not the issue you have !?

Do you use a CMS ? Panhard ?

My steering servo is still mounted to the axle.
Maybe not to scale... but seems to work fine.
I hate to spend more money on something that
might cost more money to make correct.

I'm fairly satisfied with utilizing the 4 link Ft/Rr
and really have no intentions of altering that design.

I'm on a short bus budget...
and spending money on one thing....
usually leads to spending more... in support of changes.
So... unless I can make it from scratch... I do less.

besides... less is more

OK we have same chubs...tilted back on the axle housing.

High steer knuckles and Blue Monkey Ti steering linkage will fix your issue of hitting the axle chunk and not getting max steering.

No CMS or panhard, they don't add performance and cost money. My servo is on axle too. Four link front and rear works great for me too!

[ZippoMan]

Do traxxas drive shafts have alignment marks? When I bought my Jeep they had the upgraded Traxxas shafts so just curious if it matters how they line up? I can't see any lines on them.

[IonicRipper]

Originally Posted by Natedog

My SCX axles with Axial CVDs, aluminum chubs, and high steer knuckles shakes the whole front axle at full steering lock and lots of throttle. My front end will steer until the 1.9 Ripsaws rub the shocks and lower links...driveshafts are in phase and everything is nice and tight as it gets. However, the vibration starts at about half steering to either side. I think it's because the cvds don't quite properly line up with the steering axis in the knuckles. My Wraith has no such problems using Axial universals and VP aluminum chubs and knuckles.

Sounds like we have the same exact issue.

It will only shake like so when resting upside down though. Maybe the weight of the vehicle keeps it from shaking once its on its wheels.

Even checked with my friend's scx10 (same model) and his did the same, he never even noticed before.

... So its not really a problem after all.

[TacoCrawler]

Originally Posted by ZippoMan

Do traxxas drive shafts have alignment marks? When I bought my Jeep they had the upgraded Traxxas shafts so just curious if it matters how they line up? I can't see any lines on them.

Don't know... 'cause I don't have them.

But they still need be in phase.

If there are no markings...
then align the pins that go thru the universal shafts.

You want both joints to turn, in union with each other,
at both ends of the DS(s)

otherwise the axle will jump, bobble, shake etc.
Being out of phase (sync) tends to cause the drive line to cog more as well.

Besides the odd behavior...
out of phase drive shafts will wear more quickly.
and can also break more easily.

[nigelpheron]

Did you ever solve this problem? It's driving me crazy on my rig.

[GravelMachineGun]

Bumping an old thread, Intrested if anyone found a solution. I'm having a similar problem too..

[rs10man]

interesting thread, and a few different ideas on what it could be.

my scx10ii has been doing this since playing around with link lengths, and changing driveshafts. have been pulling it apart and changing position of the shafts over and over and cant seem to get it right yet.

it is very jumpy (shudders) in reverse, is fine going forward. but have now noticed since changing tx and rx and having digital adjustable settings, that when steering full lock it will bounce the front wheels like crazy, so like someone above suggested I may need to adjust the end points.