Stub shafts - necessary to use retaining rings at diff?

[Nate Notta]

Hey all,

We just had a discussion today about whether it is necessary for us to locate our stub shafts within our diff casing using retaining rings...
With suspension travel the shaft length must change, and we want this change to be taken up in our tripot joint... but if the stub shaft (and hence the 'cup' side of the tripot) is free to slide out of the diff, the tripot (ball side) could bottom out in the cup.
Does anyone else think this presents a problem.... and do any of you guys run a diff where the stub shafts are free to slide out this way?

Thanks!

Nate Nantais
UofWindsor FSAE2004 Drivetrain

[Nate Notta]

Hey all,

We just had a discussion today about whether it is necessary for us to locate our stub shafts within our diff casing using retaining rings...
With suspension travel the shaft length must change, and we want this change to be taken up in our tripot joint... but if the stub shaft (and hence the 'cup' side of the tripot) is free to slide out of the diff, the tripot (ball side) could bottom out in the cup.
Does anyone else think this presents a problem.... and do any of you guys run a diff where the stub shafts are free to slide out this way?

Thanks!

Nate Nantais
UofWindsor FSAE2004 Drivetrain

[Denny Trimble]

We run retainers, I wonder how your splines in the LSD will like being half-engaged under the FSAE standard "CV clatter under braking" due to the single rear brake?

University of Washington Formula SAE ('98, '99, '03, '04)

[Nate Notta]

Pardon my ignorance, but can you elaborate on your post? What do you mean by "the FSAE standard 'CV clatter under braking'"?


Nate

[roadrunner]

We retain our stub shafts.
After 3 years of not retaining them we got fed up of trudging off across the grass to go find driveshafts and the such after we lost a wheel!!!!!

Word to ya moms but i came to drop bombs!!!!!

[Denny Trimble]

Many FSAE cars run single rear brakes acting on the diff. If your brake bias is correct or a little to the rear, the cv's will "clatter" when the rear wheels lock up. This leads to high shock loads on the system under braking, which may or may not be worse than the shock loads from driving torque and shifting.

University of Washington Formula SAE ('98, '99, '03, '04)

[MikeWaggoner at UW]

I'd also concerned about the splines extending (moving outward) during no-load droop, and then the car leaning in that direction under heavy loading (e.g. corner exit). This could lead to the CV tripod bearing surfaces whacking into the bottom of the CV housing, leading to flat spots and rapid wear.

-Mike Waggoner
UW