How to measure Axle Shaft Runout

[@bigstuff52]

wonderful information...your students are lucky to have you and the other instructors at WSU...

[@gregheideman36]

As far as I can tell, the surface you swept at 13:55 need not not run true (it's part of the raw casting). The face to which the wheel bolts, and the face on which the disc pads ride are where you should be measuring axial runout.

[@TheCru57]

Thanks for all the great videos. Keep up the good work.

[@MrCantfindgoodname]

Thanks for the great content and quality video. Keep up the good work :)

[@martintoma4122]

Very informative videos, awesome work, keep up the good work.

[@StratTone]

Fantastic video!! I’m gonna have to try this with my indicator on a car I have with a slight vibration.

[@mr.technician2638]

Sir, is it necessary to gave preload to dial indicator before doing final measurements?

[@84combat]

The high lateral runout with the rotor installed was probably caused by the lug nuts bottoming out on the studs at the chrome caps. The chrome cap lug nuts bottom out shortly before the rotor is clamped to the the axle flange. That has been my experience measuring TIR on the Toyota and Lexus truck rear axles like the type in your video. Therefore I use some lug nuts that have no chrome cap to clamp the rotor to the axle flange.

[@WeberAuto]

Good point, Thank you!

[@jackmama79]

@@WeberAuto do you have any idea how much radial play is acceptable on a semi floating axle wheel bearing like on a Ford 9.75 rear end with cylindrical roller bearing where the axle just slides in through the rollers? I have this and there seems to be quite a bit of up and down play and some but less for and aft play. I tried sliding a new timken onto the shaft while out of the truck and even it had noticable radial play. Thanks

[@drummerplusone]

Great info. Thanks!

[@WeberAuto]

Thank you!

[@1966johnnywayne]

I suspect that your .065" runout is due to students over torquing and warping this rotor, but consider that the recessed surface that you took your measurement from is not necessarily machined parallel to the inner wheel mounting surface. These rotors were likely rough turned on one machine and finish turned (cylindrical ground) on another during manufacturing, potentially giving two different readings...yeah, .065" sounds like a bit much, but with advancements in modern casting techniques, your indicator surface may simply be the cast surface finish. Also, cool as that roller wheel indicator tip is, any error in it must be added to the TIR. An indicator tip like that is ideal for minimizing tool wear from rough surfaces, but there is no way to know if your runout is from the part being measured or the measuring tool itself. Edit: The simplest answer usually being the correct one, I'm going to change my answer and go with with Grant Baker's answer below...the lug nuts are likely bottomed out on the studs and not applying even pressure to the rotor. That said, the points I made previously are still valid and should be considered when doing this type of measurement.

[@jacktharippares]

Thank you!

[@geojor]

thanks for sharing...

[@sksnnsksnsnsbsbb]

should've record the rotor and hub assembly rotating so we can see if it's true or not , so we can get an example of how much the rotors is wobbling