Tight spot in dana60 front pinion when rotating

[Drillsmoke]

'79 dodge dana 60 front w/ detroit and 35 spline shafts. Jeep is up on jackstands for some driveshaft love and I noticed after putting a new ujoint in my front driveshaft, that there is a rather tight spot when i try to rotate the front pinion. The pinion feels normal when spinning for 70% of the rotation, then gets really tight (when rotating tire or the driveshaft itself) then gets past the tight spot and is easy again until i get back around to the same spot. No weird noises, pinion doesn't seem to have an excessive amount of play, and no leaks. Did a little digging online and maybe a bent, or bad spot in my pinion teeth? Jeep was wheeling fine last time i took it out so doesn't seem to be a locker thing, and if it was carrier/locker related it would happen on a different frequency than every pinion rotation right?

 

[SLOWPOKE693]

I had a SxS diff that did that after a crash. Ring gear ended up being bent in one spot. Pull the cover and put a dial indicator on the side of the ring gear and find the high spot.

 

[Drillsmoke]

Interesting, if it was ring gear though would it not be every 4.88 rotations of the pinion not every single rotation like it is now?

 

[total newb]

First thing i thought was bent pinion or bad pinion tooth.
Mark it and the housing and see that its the same position each rotation.

Rings/carriers bend out not in. If it was bent id expect a loose/sloppy spot not tight. And as said, spot would match the ratio not the degrees of pinion rotation.

 

[Drillsmoke]

It is definitely the exact same yoke position each rotation. Ill pull the truss and diff cover and check it out

 

[Drillsmoke]

Would a pinion bend right before it broke? Like was i just one rev limiter short of breaking the ring and pinion?

 

[SLOWPOKE693]

Interesting, if it was ring gear though would it not be every 4.88 rotations of the pinion not every single rotation like it is now?

You are correct. I read that completely backwards.

 

[total newb]

Would a pinion bend right before it broke? Like was i just one rev limiter short of breaking the ring and pinion?

Can. Ive only ever found 1 bent pinion but 99.6% of my work was dd not offroad.

 

[Etyler2]

U joint oscillation? Did you pull the driveshafts and axle shafts and retest?

 

[Drillsmoke]

Sooo run it? Or is a bent pinion a timebomb? It is a light(ish) rigs but has a ls and a manual trans and sticky 40s

 

[Drillsmoke]

U joint oscillation? Did you pull the driveshafts and axle shafts and retest?

No havent yet, but if it was ujoints it would be in phase with the carrier right?

 

[pinchegringo]

If the ujoint is installed backwards the grease Zirk can bind when it's jacked up

 

[Drillsmoke]

If the ujoint is installed backwards the grease Zirk can bind when it's jacked up

Thats exactly what it was! The bumpout on the ujoint for the zerk was hitting the end of the pinion nut. Thanks! Way cheaper than buying gears😭