pinion play

[we kool]

can anybody tell me how much play should be in my rear yoke with the driveshaft out I can twist the pinion about 3/8 to 1/4 of an inch it,s a 12 bolt with a spool 456 gears . any help will be appreciated thanks

[CoMax Racing]

If I understand you correctly,you have a big problem. You should feel only a slight movement. The lash on those gears should be only .008"-to .012" and you should feel even less of that amount at the yolk. If you can rotate the yolk that much there is damage or your pinion nut has backed off allowing the lash to increase a large amount. Don't run it untill you find out the problem and fix it.

[Craig W.]

You'll feel a lot more movement when twisting the yoke than you will when measuring the backlash (rocking the ring gear). My gears are setup with .012" backlash and I can rock the yoke well over .100". If the gears were really that loose, they'd howl like a banshee. I've had a pinion nut back off before and it let me know it. Very noisy.

If you want to err on the safe side (always a good idea), pull the cover off and check things out. Measure the backlash, inspect the teeth and be sure there is no fore and aft movement of the pinion gear.

[a1elec]

speaking of pinion nuts has anyone changed a pinion seal on a 12 bolt witout replacing crush sleeve? i have heard anytime you backoff pinion nut you have to replace crush sleeve. thanks john

[Craig W.]

Yeah, its commonly done. Make a mark on the yoke, one on the nut and one on the end of the pinion. Mark them so that they all line up. Then remove the nut, replace the seal and put the nut back on. When it starts getting tight, torque it until all the marks line up again. That's the dealership method.