Drive line slop

[exb5182]

Ok so here's my situation I installed a lowmile 8.6 and before I drove with it switched the gears from 3.42 to 4.56 I ran it for about 500 miles with just the original spider gears in it I had a backlash of .006 and a great pattern with some load on the bearings. The more and more I drove the more slop I noticed in the drive train mainly when shifting from p to r to n to d... I got under it and you can see the drive shaft move a great but befor the rear catches... you feel it while its in neutral and you can feel the very slight r&p back lash but it moves a whole lot like u spin the ring gear... so I figured I had some play in the spiders. So on friday when I put my powertrax in I expected it to disappear... I rechecked the lash and pattern just to be sure both were still the same and yes I check my pattern with slight break pressure to load the rear a bit. Anyway it still has a reap good amount of slop before my rear seems to catch. I know its not the r&p backlash... its quiet while driving just the initial clunk... my axles didnt appear warn down either so im scratching my head a bit... any help would be appreciated thanks Ed

[DustinC1989]

You said it does it when you change gears, U-Joints?

[exb5182]

No they're all tight like the whole drive shaft spins and the yoke

[Aries]

exb5182 I have the exact same issue as you! I had some drive line movement before my gear change and powertrax but it wasn't as noticeable as it is now. I checked "everything" twice over same as you did and everything checked out ok. I even went as far as thinking it was my transfer case but after much research I ruled that out. It drives fine on and off road and I love the powertrax traction. I'm gonna leave it for now but I have plans to install a completely new rebuilt 8.6 in the future.


Here's a video I sent to an expert driveline shop for their opinion

[HARDTRAILZ]

I have similar clunking into gear. I talked with Barton about it and we both agreed that it was likely in the TC. He knew more of the issue than I did. Seems fairly common if I remember right. He basically said dont worry about it. I could be mis-remembering, but I have just accepted it since there seem to be no issues from it. I am sure he will chime in when he gets a chance and can share his knowledge.

[ErikSS]

As process of elimination works, I would put the transmission in neutral, and turn the driveshaft by hand back and forth. That will tell you how much "play" you have in your rear differential. If it moves a simular amount as I see it moving in the video then you're clunking is likely from your rear differential having some wear and tear. Still probably not all that big of a deal, but it would help narrow the cause.

[HARDTRAILZ]

I have checked the rear diff and eliminated it as culprit just like the other posters stated they have.

[v7guy]

I'd also assume it's in the case, that's a nice middle of the road backlash. Your pattern is a smidge deeper than mine, but it's good.

[exb5182]

Lol sorry I haven't been on in a while... when I have it in neutral you can feel the lash so lightly but the shaft keeps spinning I have just accepted it as stated above its definitely in the tc. I checked the fluid and topped it off with some blue slime. I jist started using my e brake everytime I park even on completely flat ground and it makes the it a little less noticeable it just threw me off bc it was no where near the amount it was before the gear change but I guess making the ratio steeper exaggerated it.