play in diff

[d0ubledown]

ok, so in trying to assess my whir...i came across some play in the rear driveshaft. should there be any play in the driveshaft when i spin it? wheels are off the ground, tcase and tranny in neutral. i'll spin the driveshaft both ways, and there seems to be a little bit of play (before it actually engages and spins a wheel) when i go back and forth. is this normal? if so..how much is a normal amount? i have yet to drain some diff oil to see if any nasties come out...

i originally thought the whir was a wheel bearing, which it could still be. but after noticing this, im fearing there might be more going on in the pinion or diff. the whir is wheel speed, but it doesnt get louder if i apply throttle or get quieter if i let off the throttle. only becomes noticable on or above 50km/h (approx 32mph)

please dont tell me i'll have to pull my diff again and have it checked :chair: :gay:

thanks

[neliconcept]

sounds like a ujoint in the driveshaft to me, but im not totally sure

[20005spd]

id check the u joints 1st, but if those are fine and you have alot of play before the wheels turn then there is most likely something wrong with the diff. especialy since you say you notice a whir type noise above 50mph. just drain the diff fluid and see what you got. have you drained the fluid lately? also does the whir noise change at all if you turn pretty hard to one side. if it was a rear wheel bearing you could single it out that way.

[97kurt]

When was the last time you greased the u-joints?

[AxleIke]

You'll have to give a better amount on "play".

I can wiggle my rear driveshaft back and forth a good half inch with the wheels off the ground. More than that I'd say you have pinion preload issues.

[Lee]

sounds like a ujoint in the driveshaft to me, but im not totally sure


When was the last time you greased the u-joints?


x2 on these

[all_terrain17]

You'll have to give a better amount on "play".


Yeah really.

I've got a full quarter turn worth of rear driveshaft play with wheels on the ground. Dunno if it's just the lunchbox style locker or whether the "professional" gear setup wasn't so good.

[d0ubledown]

ujoints are good, just had the rear replaced last summer. joints are also greased frequently...after each outing and at oil changes.

i get maybe quarter inch worth of rotation from measuring a marking on the flange. wheels off the ground. this is normal amount of play. took it into the shop, they couldnt figure out which end its coming from...loud tires dont excactly help in diagnosing. they said its probably on its way out, but all corners seem to be tight. going to take it back for front right bearing next week. if problem persists...i'll go right rear. im leaning its on the passenger side as it gets louder as i make left turns.

gonna drain some diff fluid out...hopefully nothing but gear oil comes out.

[d0ubledown]

ok...so i drained some diff fluid to see what came out. on the magnet of the drain plug..it looks like there was some metal shavings present...but found no more in my drain pan. should this be a cause for concern?

didnt want to do a full drain as i only had less than a liter of gear oil on me...so i'll grab some more and do a full flush and fill.

[GSGALLANT]

1/4 inch of rotational play of the driveshaft is about normal. What you're feeling is backlash in the gears. Grab the flanges that come out of the diffs and push up and down and side to side. Any play in those directions is bad, and would mean that you either have bad pinion bearings, or no preload on the pinion bearings. Either of those two cases can lead to "funny" wearing on the gears, which can cause a whirring or whining sound. You can also check the transfer case flanges for play this way.

...and a grey metallic paste on the drain plug magnet is OK. Large distinctive pieces of metal mean something is not right.

[d0ubledown]

thanks gsgallant. yeah i do have a bit of grey metallic paste on the plug, no solid pieces of metal though...thank goodness.

i'll have a check on the drive flanges again today. i didnt notice any play on em when i was doing my original inspection.

also, with this whir, it doesnt make a difference if i make turns. guy that did my diffs said that since its semifloating rears, its not load bearing...so there wouldnt be an increase/decrease in noise if i made sharp turns at speed. i thought it was the FF's that dont have the load on the bearing? maybe im confused...nonetheless, its pretty much constant wheel speed. no change if im on/off throttle or turning.

...and my damn tires are so loud its hard to diagnose! aargh. anyway...gonna bring it to the shop to see if they can put it on the hoist and stick a stethescope to it...

[AxleIke]

no, semi float is load bearing. FF is not load bearing.

[20005spd]

You'll have to give a better amount on "play".


Yeah really.

I've got a full quarter turn worth of rear driveshaft play with wheels on the ground. Dunno if it's just the lunchbox style locker or whether the "professional" gear setup wasn't so good.
i had alot of play when turning the d shaft with the lock right in since the locker was locking and unlocking when you do that. its pretty normal, if i had that same type of play with a spool or welded or regular open diff then i would be worried. i think even a detriot locker would give you that same amount of play since it locks and unlocks to.