CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

2006 Rubicon Unlimited

okay, that makes sense and I can see that (the lightbulbs are slowly getting lit, I am old so they are incandescent instead of LED)
So the engine inputs the RPM at 2536RPM to the transmission input shaft.

The transmission ratio is 0.69 which means the input shaft turns 0.69 times to every one revolution of the output shaft, which is turning at 3675rpm Since the transfer case is in high range which is 1:1, the input and output speeds are still 3675rpm which is also the speed of the driveshaft and the pinion.

The pinion then spins 5.13 times per every revolution of the axle shaft, dropping the axle shaft speed to 716 RPM.

same reply. thank you; like I said, it is starting to make sense. so my formula I found is actually for axle shaft instead of pinion?
 
No, was in a hurry and had a "it's close enough" moment. The pinion doing nearly 4k rpm at 70mph with these 5.13s and 33s didn't do me any favors either. LOL.

sounds like it needs 37s; I think it has been said on here that 37s are the new 33s.
 
OK. Added 0.010 to the pinion. Then moved 0.005 to the PS to increase backlash as indicated by the Jeep service manual page.

I'm here now. It got below freezing and my Charmin soft butt packed it in for the night. LOL.

1000022405.jpg

1000022406.jpg

1000022407.jpg
 
Did you put good resistance on the ring gear? And maybe a little more compound? Run another pattern when you can.
 
Did you put good resistance on the ring gear? And maybe a little more compound? Run another pattern when you can.
It changed between the first test and 2nd. 3rd test will be this evening. It got WAY colder than I was willing to work in after the sun went down.
 
Moved it over 0.020 and got this weirdness.

1000022414.jpg
1000022415.jpg

Dropped it back 0.005

1000022416.jpg

Added 0.005 to the pinion.
1000022417.jpg

The added another 0.005 to the pinion
1000022420.jpg
 
Still dont see it.

Set the gears back to where I started. 0.005 BL

1000022464.jpg

1000022463.jpg
 
1000022479.jpg

1000022480.jpg

Ended here. Centered on coast, toe heavy on drive. Manual said focus on coast pattern on used gears and showed a similar pattern to this as "acceptable". 0.006" backlash.

1000022493.jpg

Now the aggravating part.... The whine is still there. No change in it at all. So now I'm 90% certain it's the rear transfercase output bearing.
 
View attachment 518398

View attachment 518399

Ended here. Centered on coast, toe heavy on drive. Manual said focus on coast pattern on used gears and showed a similar pattern to this as "acceptable". 0.006" backlash.

View attachment 518397

Now the aggravating part.... The whine is still there. No change in it at all. So now I'm 90% certain it's the rear transfercase output bearing.
Still I think you are better off now with that rear axle, it wasn't a good setup.
 
So you put new bearings in and reused the same gears?
Yeah. I've done some whacky things with gears over the years and never had this kinda noise.

I used to "quick change" gear sets in my S10 by just swapping pinions and carriers and reuse the pinion races in the housing. I put probably 40k miles on my old Cherokee having done that to both front and rear diffs to go from 3.07 to 3.55 with a set of used gears a friend gave me.
 
Last edited:
Yeah. I've done some whacky things with gears over the years and never had this kinda noise.

I used to "quick change" gear sets in my S10 by just swapping pinions and carriers and reuse the pinion races in the housing. I put probably 40k miles on my old Cherokee having done that to both front and rear diffs to go from 3.07 to 3.55 with a set of used gears a friend gave me.
I get that, I’ve done the same but if your gears got that hot I’m thinking they are pickeled. These were new gears right? Then they got super hot
 
Did you use a case spreader?

What happens if you move the carrier to the left and run the pinion deeper? Trying to keep the pattern centered between the face and flank but move it closer to center on the drive side between toe and heel, even if it moves the coast side a bit.

Looking at your wear where the paint isn't, I think you're off a bit. So I can squish out the paint better, I use ratchet on the pinion and use a pry bar to provide resistance on the carrier.

With used gears you mostly care about the coast side, but not at the cost of completely disregarding the drive side. The reason for that is because it's hard to get a good pattern on worn gears on the drive side because they already "wore in", but your gears aren't really worn.
 
Top Bottom