Odd pinion bearing preload
07-18-2007, 07:48 PM
#1
Odd pinion bearing preload Im assembling a rear for a friend..having a little snag. The pinion bearing preload varies as you spin the pinion shaft. It will be 25 in lbs then shoot up to 70 then back down to 25.
Im feeling that the crush collar may be fugged up. I basically rebuilt this entire rear..everything is new. New races, bearings, gears. I made sure that the races were bottomed out in the holes.
Can anyone help me out?
Im feeling that the crush collar may be fugged up. I basically rebuilt this entire rear..everything is new. New races, bearings, gears. I made sure that the races were bottomed out in the holes.
Can anyone help me out?
07-19-2007, 08:46 AM
#7
Let me get this straight... You have the pinion installed, with the crush sleeve crushed...and while setting pre-load, you are feeling a bind in the pinion? As in...you put the torque wrench on the nut, and start to turn it, and while keeping it turning you feel it snag??
Is it snagging in the same spot everytime? If it is, sounds like you have a bearing issue. Whether its something that isnt seated all the way, or a faulty bearing. Once the crush sleeve starts to crush, it shouldnt matter...unless somehow its squeezed out and the sides are hitting something. At that point, I doubt you'd even be able to turn it because that would be crazy pre-load.
If I were you, and hopefully you got some spare crush sleeves for just such an occasion, Ide loosen it back up and check things out. Unless you can see something obvious. When you put the pinion seal in, did you use RTV? Did you drip some down in the outter bearing maybe? With the bearings lubed (first thing I thought of when I read your post), you shouldnt feel any resistance until you start to crush the sleeve. Should spin nice and free.
Also, if you are using new gears, dont just assume the old shims will work. You still should run a set up on the new gears. Get pinion depth set, make sure backlash and pattern are in good shape...all that jazz. I dont see how pinion depth would cause your particular issue...but just thought ide throw that in there.
J.
Is it snagging in the same spot everytime? If it is, sounds like you have a bearing issue. Whether its something that isnt seated all the way, or a faulty bearing. Once the crush sleeve starts to crush, it shouldnt matter...unless somehow its squeezed out and the sides are hitting something. At that point, I doubt you'd even be able to turn it because that would be crazy pre-load.
If I were you, and hopefully you got some spare crush sleeves for just such an occasion, Ide loosen it back up and check things out. Unless you can see something obvious. When you put the pinion seal in, did you use RTV? Did you drip some down in the outter bearing maybe? With the bearings lubed (first thing I thought of when I read your post), you shouldnt feel any resistance until you start to crush the sleeve. Should spin nice and free.
Also, if you are using new gears, dont just assume the old shims will work. You still should run a set up on the new gears. Get pinion depth set, make sure backlash and pattern are in good shape...all that jazz. I dont see how pinion depth would cause your particular issue...but just thought ide throw that in there.
J.
Last edited by ghettocruiser; 07-19-2007 at 08:52 AM.
Trending Topics
07-19-2007, 11:33 AM
#9
LS1Tech Sponsor
iTrader: (22)
Join Date: Mar 2005
Location: 32639 Groesbeck HWY. Fraser MI 48026
Posts: 1,593
Likes: 0
Received 0 Likes
on
0 Posts
Dirt in the pinion bearings will cause preload to move around. Did you also smack the pinion, front and back, to seat the races in the housing?
07-19-2007, 02:19 PM
#10
Yeah...also, if there was a burr or a piece of crap in the race seat, you could have smacked it in, and thought it was down all the way, but it could infact be alittle off. Just really sounds like "dirty" bearings or something not seated/aligned right.
J.
J.
07-19-2007, 08:06 PM
#12
11 Second Club
iTrader: (20)
Join Date: Oct 2006
Location: Virginia
Posts: 3,131
Likes: 0
Received 0 Likes
on
0 Posts
^^^^^Ive done a ton of rearends and never had to pack a bearing with grease.....maybe the outer bearings on a ton truck but never a car......
i would disasemble it and make sure the racesc are seated.....
i would disasemble it and make sure the racesc are seated.....
07-19-2007, 08:07 PM
#13
11 Second Club
iTrader: (20)
Join Date: Oct 2006
Location: Virginia
Posts: 3,131
Likes: 0
Received 0 Likes
on
0 Posts
wtf
Originally Posted by HFLDtA
Get some paint and put it on your ring gear ( about 5 teeth) & see what you contact pattern looks like. If thats not it then it has to be in the bearing (Pinion or possibly carrier). Hope this helps. Let us know if you fixed it because Ive never heard of this one.
pinion setup...lol
07-19-2007, 08:50 PM
#14
Thanks for the help everyone..i appreciate it.
I grabbed another crush sleeve...pulled everything apart. I backtracked all of my steps and made sure the races were totally seated...teh bearings didnt have any crud on them, and that the pinion shaft wasnt bent.
nothing seemed to be out of place. for safe measure i put a little lube on the bearings when i reinstalled them.
Put a new crush sleeve on...went through the process...and it went perfect.
I got the preload right on the money. Spins fine..has a constant reading.
i spoke to richmond today and they said what i was experiencing was normal...but i wanted to be sure before i blew this kids rear into a million pieces.
Again..i really appreciate everyones input...you all helped me in some way..either by eliminating what it wasnt..or steering me in the right direction.
I grabbed another crush sleeve...pulled everything apart. I backtracked all of my steps and made sure the races were totally seated...teh bearings didnt have any crud on them, and that the pinion shaft wasnt bent.
nothing seemed to be out of place. for safe measure i put a little lube on the bearings when i reinstalled them.
Put a new crush sleeve on...went through the process...and it went perfect.
I got the preload right on the money. Spins fine..has a constant reading.
i spoke to richmond today and they said what i was experiencing was normal...but i wanted to be sure before i blew this kids rear into a million pieces.
Again..i really appreciate everyones input...you all helped me in some way..either by eliminating what it wasnt..or steering me in the right direction.
07-19-2007, 09:52 PM
#15
Originally Posted by 5_02ls1
^^^^^Ive done a ton of rearends and never had to pack a bearing with grease.....maybe the outer bearings on a ton truck but never a car......
i would disasemble it and make sure the racesc are seated.....
i would disasemble it and make sure the racesc are seated.....
Ping King: Thought you said before that you did put oil/lube on the bearings... It just makes them move smoother. Glad you got it figured out! I dont usually like setting up axles for other people...althought I do it quite often. I hate when I hit snags like that because it always makes me nervous, ESPECIALLY for that first drive. haha. Every little rattle or clunk makes me think the rear is gonna blow.
J.
07-20-2007, 12:42 AM
#17
TECH Fanatic
Pinion pre-load is set by itself... without the carrier being installed. The carrier bearing pre-load would be at the same time you were setting backlash.
Sometimes, with the carrier installed, if there is any measureable run-out... it can give you the same feel as what was originally described. To see what it 'looks' like, I paint about 4-5 teeth in a row... three to four places on the ring gear. Then if it shows me any weirdness... Ill throw the dial indicator to it and measure the actual run out.
A bearing cage can also cause this same feeling... although, it will leave a 'witness' mark, and its pretty easy to find.
I would not however, recommend that you use the pinion (and its bearing) to seat the inner races... by knocking it back and forth. Use or make a simple bearing driver out of the bearing races that you pulled out of the differential. If you use the pinion... you greatly increase the possibility of bearing damage and premature bearing failure. It will cause or create a condition known as 'impact brinelling'. By hammering the bearing rollers (which are very hard) into the races themselves (which are much softer), it will create hardened spots on the race surface that will eventually lead to micro spalling... which will lead to failure and quickly I might add.
FWIW, I only use a parrfin based assembly lube (Schaffers) for the set-up and it is rather viscous. I also use a pretty liberal amount...
Sometimes, with the carrier installed, if there is any measureable run-out... it can give you the same feel as what was originally described. To see what it 'looks' like, I paint about 4-5 teeth in a row... three to four places on the ring gear. Then if it shows me any weirdness... Ill throw the dial indicator to it and measure the actual run out.
A bearing cage can also cause this same feeling... although, it will leave a 'witness' mark, and its pretty easy to find.
I would not however, recommend that you use the pinion (and its bearing) to seat the inner races... by knocking it back and forth. Use or make a simple bearing driver out of the bearing races that you pulled out of the differential. If you use the pinion... you greatly increase the possibility of bearing damage and premature bearing failure. It will cause or create a condition known as 'impact brinelling'. By hammering the bearing rollers (which are very hard) into the races themselves (which are much softer), it will create hardened spots on the race surface that will eventually lead to micro spalling... which will lead to failure and quickly I might add.
FWIW, I only use a parrfin based assembly lube (Schaffers) for the set-up and it is rather viscous. I also use a pretty liberal amount...
07-20-2007, 06:28 AM
#18
When I do set ups... I install the pinion to the correct depth, then put on the yoke and nut and get some preload on it. Then I install the carrier, check backlash and pattern, and adjust as needed. The preload isnt really that important at that point. As long as the pinion is drawn back as far as it will be during final assembly, it should be fine. After I get a good pattern, and BL is in spec, I tear it all apart. Re-check everything, install the crush sleeve and get my final pre-load. Then put it back together and re-check all my previous settings. At this point, I usually add the .003 shims for the carrier preload. USUALLY this all goes like clock work, and the more time you take doing a trial set-up, the better it comes out.
Ive never been inside a 10 bolt, so I dont know where the carrier shims are. But if they are under the carrier bearings, its also a good idea to make set up bearings. Just slighty ream the inner mating surface so you can slide them on and off by hand. Just makes things a ton easier. I do the same for the pinion. That way I can set depth and all, and dont have to press the bearing back off.
Justin
Ive never been inside a 10 bolt, so I dont know where the carrier shims are. But if they are under the carrier bearings, its also a good idea to make set up bearings. Just slighty ream the inner mating surface so you can slide them on and off by hand. Just makes things a ton easier. I do the same for the pinion. That way I can set depth and all, and dont have to press the bearing back off.
Justin
07-20-2007, 06:50 PM
#19
well i got it all together...rotated it by the rear wheels and notice that theres a very very faint ratcheting sound when going in reverse direction. This is a brand new set of gears so im not sure if its just not broken in or what.
theres also a set of spider gears in this rear..not sure if they could be causing the sound. Ive built transmissions, engines, and all that jazz, but this is my first rear..so im trying to make sure its dead on.
theres also a set of spider gears in this rear..not sure if they could be causing the sound. Ive built transmissions, engines, and all that jazz, but this is my first rear..so im trying to make sure its dead on.
