Need help! Posi unit is stuck.
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
Need help! Posi unit is stuck.
Just finished setting up new ring and pinion in my differential. the results are perfect gear pattern and preload on pinion is good. My problem is I need to take the posi unit back out to punch out the side yoke bearing that I screwed it up putting it in. It seems that my posi unit is stuck and wont come out, I put the shims in and dropped it about half way in then took a rubber mallet at drove it in and tightened the caps. Now I need to remove it to get to a the side yoke bearing and it wont budge. Has anyone had this problem before? I was wondering if I put ice on it would the metal shrink some what and help get it out. Just want to take it out quick and drop it back in.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Just finished setting up new ring and pinion in my differential. the results are perfect gear pattern and preload on pinion is good. My problem is I need to take the posi unit back out to punch out the side yoke bearing that I screwed it up putting it in. It seems that my posi unit is stuck and wont come out, I put the shims in and dropped it about half way in then took a rubber mallet at drove it in and tightened the caps. Now I need to remove it to get to a the side yoke bearing and it wont budge. Has anyone had this problem before? I was wondering if I put ice on it would the metal shrink some what and help get it out. Just want to take it out quick and drop it back in.
When properly set up with a .005" side bearing preload it does take some effort to pull the differential case out. It can be pried out using a length of pipe or other pry bar.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Just finished setting up new ring and pinion in my differential. the results are perfect gear pattern and preload on pinion is good. My problem is I need to take the posi unit back out to punch out the side yoke bearing that I screwed it up putting it in. It seems that my posi unit is stuck and wont come out, I put the shims in and dropped it about half way in then took a rubber mallet at drove it in and tightened the caps. Now I need to remove it to get to a the side yoke bearing and it wont budge. Has anyone had this problem before? I was wondering if I put ice on it would the metal shrink some what and help get it out. Just want to take it out quick and drop it back in.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Put a box end wrench on one of the ring gear bolts. Use the pinion and turn the case until the wrench is against he case, turn it a little more and it will drive it out. I don't remember which way to put the wrench, but one way it will come out pretty easy- even with way too much preload.
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
Put a box end wrench on one of the ring gear bolts. Use the pinion and turn the case until the wrench is against he case, turn it a little more and it will drive it out. I don't remember which way to put the wrench, but one way it will come out pretty easy- even with way too much preload.
Race Director
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
Use a big 2-jaw pulley puller. Bridge the casing with a 2x4 block on each side and a big adjustable wrench handle or flat bar between the blocks. Then, put the puller over the wrench and grab the windows in the carrier with the jaws. Tighten the screw against the wrench and pull it out.
Last edited by lionelhutz; Dec 16, 2015 at 09:59 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
Use a big 2-jaw pulley puller. Bridge the casing with a 2x4 block on each side and a big adjustable wrench handle or flat bar between the blocks. Then, put the puller over the wrench and grab the windows in the carrier with the jaws. Tighten the screw against the wrench and pull it out.
Race Director
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
Yes, it will work without damaging the carrier. The pieces between the windows takes the forces from the spider gears trying to push them apart, so they're quite capable of being pulled on.
Advanced
Joined: Oct 2010
Posts: 80
Likes: 2
From: near Nuremberg Bavaria
Just for completeness: The "official" way of getting the carrier in & out of the case is by using a case spreader, which takes the preload off of the posi unit during (un)install. There are OEM and/or aftermarket versions around I believe, but one can DIY them too.
Burning Brakes
Joined: Aug 2008
Posts: 878
Likes: 55
From: Deep South Denmark
Put a box end wrench on one of the ring gear bolts. Use the pinion and turn the case until the wrench is against he case, turn it a little more and it will drive it out. I don't remember which way to put the wrench, but one way it will come out pretty easy- even with way too much preload.
This is how I did it.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
tracdogg2 is busy building differentials, tuning posi's, machining bearing caps. But always makes time to answer the phone when someone has a problem.
How far did you install the axle bearings?
Did you reuse the cast iron side shims or did you use super shims?
Did you use the caps to finish pulling the carrier in?
Tim has the best idea. Use a prybar on one of the ring gear bolts at the 12 o'clock position. Use the case as the pivot point. Hold the pinion to keep it from rotating. Once it starts to move, rotate the pinion to re-position the ring gear bolt back to the 12 o'clock position. This will work only so far, until the r&p no longer make contact. From there the stub axle bores should out exposed enough to walk the carrier out.
Once the carrier is out look at the side bearing races for damage from the edges of the rollers. One or both of the races had to go in at an angle for the carrier to be this tight.
The stub axle bearings MUST be installed with the carrier out in order to set the depth. If you install the bearings at the depth of the seal step, or deeper, they will protrude into the case and prevent the side shims from sliding out with the carrier.
Mike
How far did you install the axle bearings?
Did you reuse the cast iron side shims or did you use super shims?
Did you use the caps to finish pulling the carrier in?
Tim has the best idea. Use a prybar on one of the ring gear bolts at the 12 o'clock position. Use the case as the pivot point. Hold the pinion to keep it from rotating. Once it starts to move, rotate the pinion to re-position the ring gear bolt back to the 12 o'clock position. This will work only so far, until the r&p no longer make contact. From there the stub axle bores should out exposed enough to walk the carrier out.
Once the carrier is out look at the side bearing races for damage from the edges of the rollers. One or both of the races had to go in at an angle for the carrier to be this tight.
The stub axle bearings MUST be installed with the carrier out in order to set the depth. If you install the bearings at the depth of the seal step, or deeper, they will protrude into the case and prevent the side shims from sliding out with the carrier.
Mike
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
tracdogg2 is busy building differentials, tuning posi's, machining bearing caps. But always makes time to answer the phone when someone has a problem.
How far did you install the axle bearings?
Did you reuse the cast iron side shims or did you use super shims?
Did you use the caps to finish pulling the carrier in?
Tim has the best idea. Use a prybar on one of the ring gear bolts at the 12 o'clock position. Use the case as the pivot point. Hold the pinion to keep it from rotating. Once it starts to move, rotate the pinion to re-position the ring gear bolt back to the 12 o'clock position. This will work only so far, until the r&p no longer make contact. From there the stub axle bores should out exposed enough to walk the carrier out.
Once the carrier is out look at the side bearing races for damage from the edges of the rollers. One or both of the races had to go in at an angle for the carrier to be this tight.
The stub axle bearings MUST be installed with the carrier out in order to set the depth. If you install the bearings at the depth of the seal step, or deeper, they will protrude into the case and prevent the side shims from sliding out with the carrier.
Mike
How far did you install the axle bearings?
Did you reuse the cast iron side shims or did you use super shims?
Did you use the caps to finish pulling the carrier in?
Tim has the best idea. Use a prybar on one of the ring gear bolts at the 12 o'clock position. Use the case as the pivot point. Hold the pinion to keep it from rotating. Once it starts to move, rotate the pinion to re-position the ring gear bolt back to the 12 o'clock position. This will work only so far, until the r&p no longer make contact. From there the stub axle bores should out exposed enough to walk the carrier out.
Once the carrier is out look at the side bearing races for damage from the edges of the rollers. One or both of the races had to go in at an angle for the carrier to be this tight.
The stub axle bearings MUST be installed with the carrier out in order to set the depth. If you install the bearings at the depth of the seal step, or deeper, they will protrude into the case and prevent the side shims from sliding out with the carrier.
Mike
Last edited by flyguy767; Dec 17, 2015 at 04:27 PM.
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
tracdogg2 is busy building differentials, tuning posi's, machining bearing caps. But always makes time to answer the phone when someone has a problem.
How far did you install the axle bearings?
Did you reuse the cast iron side shims or did you use super shims?
Did you use the caps to finish pulling the carrier in?
Tim has the best idea. Use a prybar on one of the ring gear bolts at the 12 o'clock position. Use the case as the pivot point. Hold the pinion to keep it from rotating. Once it starts to move, rotate the pinion to re-position the ring gear bolt back to the 12 o'clock position. This will work only so far, until the r&p no longer make contact. From there the stub axle bores should out exposed enough to walk the carrier out.
Once the carrier is out look at the side bearing races for damage from the edges of the rollers. One or both of the races had to go in at an angle for the carrier to be this tight.
The stub axle bearings MUST be installed with the carrier out in order to set the depth. If you install the bearings at the depth of the seal step, or deeper, they will protrude into the case and prevent the side shims from sliding out with the carrier.
Mike
How far did you install the axle bearings?
Did you reuse the cast iron side shims or did you use super shims?
Did you use the caps to finish pulling the carrier in?
Tim has the best idea. Use a prybar on one of the ring gear bolts at the 12 o'clock position. Use the case as the pivot point. Hold the pinion to keep it from rotating. Once it starts to move, rotate the pinion to re-position the ring gear bolt back to the 12 o'clock position. This will work only so far, until the r&p no longer make contact. From there the stub axle bores should out exposed enough to walk the carrier out.
Once the carrier is out look at the side bearing races for damage from the edges of the rollers. One or both of the races had to go in at an angle for the carrier to be this tight.
The stub axle bearings MUST be installed with the carrier out in order to set the depth. If you install the bearings at the depth of the seal step, or deeper, they will protrude into the case and prevent the side shims from sliding out with the carrier.
Mike
Last edited by flyguy767; Dec 18, 2015 at 11:04 AM.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Since you did get the carrier to move, remove the cross shaft and use a long soft punch to drive the bearing outward. It sounds like you drove the bearings in so far that they are now catching the side bearing outer races.
The bearings should be flush, or just shy of, the inside of the case.
The bearings should be flush, or just shy of, the inside of the case.
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
Since you did get the carrier to move, remove the cross shaft and use a long soft punch to drive the bearing outward. It sounds like you drove the bearings in so far that they are now catching the side bearing outer races.
The bearings should be flush, or just shy of, the inside of the case.
The bearings should be flush, or just shy of, the inside of the case.
flyguy767
Last edited by flyguy767; Dec 18, 2015 at 02:20 PM.