New thread: Unleash the Kraken!

-
VonCramp

VonCramp

Well-Known Member
Joined
Oct 25, 2011
Messages
529
Reaction score
27
Location
League City
So, at this point I have figured out the driver's side axle is bottoming out. It is 7/16" shy from seating in the axle flange. The passenger side goes in perfect. When I tried to use the flange to suck the axle inward it resulted in the axle locking against whatever it is bottoming out on. Pulled the third member and took back to builder. He says splines may or may not be lined up. He believes they are though. He wants to shorten one axle by 7/16". Taking the axle and third member to another shop for second opinion.
 
Damn, you are going to be a pro when that car is done. :)

Good call on the second shop.
 
Find out what's wrong first before having someone taking a grinder to the axleshaft.
I'm sure you backed off the adjuster plenty on the pass.side axle?
 
You can check the spline alignment simply by putting the axles into the 3rd member out of the housing. IN fact, that is what should be done BEFORE putting the 3rd member into the housing so that the axles will then slip in correctly....per my '62 Mopar FSM BTW.

7/16" is ridiculous UNLESS this is a new mix and match of axle parts. Don't do it with just opinions from shops. I think this has been suggested but bears repeating:
- Run a long thin measurement device like a 1/2" PVC pipe through the axle with everything out and measure the end-to-end distance from where the axle bearings seat in the tube ends.
- Then measure the distance from the bearing seating surfaces to the axle ends on both axle assemblies. Add the 2 lengths and then subtract from the first measurement.
- You should be able to closely figure out this number; it ought to be a small number and be almost exactly equal to the thrust button separation length inside the ring gear carrier. If you measure carefully, then your reults will be WELL within the tolerance of 7/16".

Once this is done and IF you really need to take 7/16" off the axle end, then you nned to do another measurement unless someone can verify that the splines will still be long enough.
- Measure the axle from the bearing's seating surface to the end of the splines on the axle and add about 3/16".
- Then measure from the axle bearings seating surface in the tube to the end of the diff as installed in the housing.
See if the first measurment is smaller than the 2nd; if not then the axle splines will be too short even with the axle cut off.

What ever happened with the info that the yoke had backed out 1/2"?

Seriously, PLEASE, you NEED to do this measurment regardless of any shop opinions. The 3rd member assembler is not going to do this for you unless you pay him; he can only be surmising what MIGHT be the issue. Since you are the final axle assmebler, you need to do all the proper measurements to be sure. Maybe you can pay the 2nd shop to do this instead....??
 
BigBlockMopar said:
Find out what's wrong first before having someone taking a grinder to the axleshaft.
I'm sure you backed off the adjuster plenty on the pass.side axle?
Click to expand...
No adjuster. Green bearings now. All of this trouble is from using two different shops. It's my fault because I didn't want to make the trip to the one pro-shop I knew of.
 
nm9stheham said:
You can check the spline alignment simply by putting the axles into the 3rd member out of the housing. IN fact, that is what should be done BEFORE putting the 3rd member into the housing so that the axles will then slip in correctly....per my '62 Mopar FSM BTW.

7/16" is ridiculous UNLEI SS this is a new mix and match of axle parts. Don't do it with just opinions from shops. I think this has been suggested but bears repeating:
- Run a long thin measurement device like a 1/2" PVC pipe through the axle with everything out and measure the end-to-end distance from where the axle bearings seat in the tube ends.
- Then measure the distance from the bearing seating surfaces to the axle ends on both axle assemblies. Add the 2 lengths and then subtract from the first measurement.
- You should be able to closely figure out this number; it ought to be a small number and be almost exactly equal to the thrust button separation length inside the ring gear carrier. If you measure carefully, then your reults will be WELL within the tolerance of 7/16".

Once this is done and IF you really need to take 7/16" off the axle end, then you nned to do another measurement unless someone can verify that the splines will still be long enough.
- Measure the axle from the bearing's seating surface to the end of the splines on the axle and add about 3/16".
- Then measure from the axle bearings seating surface in the tube to the end of the diff as installed in the housing.
See if the first measurment is smaller than the 2nd; if not then the axle splines will be too short even with the axle cut off.

What ever happened with the info that the yoke had backed out 1/2"?

Seriously, PLEASE, you NEED to do this measurment regardless of any shop opinions. The 3rd member assembler is not going to do this for you unless you pay him; he can only be surmising what MIGHT be the issue. Since you are the final axle assmebler, you need to do all the proper measurements to be sure. Maybe you can pay the 2nd shop to do this instead....??
Click to expand...
I measured as suggested by your reply. I arrived at the 7/16" measurement this way. I even had the 1/2" PVC pipe handy. If the axle is ruined I will have to buy another I guess. I have gotten myself in a mess by not dealing with strictly one shop. Changing the third member and bearings got me into trouble. I was told by Dr.Dif that the thrust button in or out doesn't matter. Others have said it does matter. I don't know anymore.
 
If your "builder" does not know how to align the splines, then you need to take your stuff and run. ALL you have to do is remove the carrier, loosen the bolts holding it together, install the axles in either side and gently turn them to align the splines. Then with the axles still in place, retighten and torque the case bolts. That guy is beginning to sound like the world's biggest idiot.
 
Since you are using the green bearings you no longer need the thrust button.
If your new center section has one you may be able to remove it to gain the needed
space for the axle to seat. I would check this first.
Most aftermarket axles have extra long splines and can be trimmed and still have full spline engagement into the side gears.
Really no need to pay another shop if you can read a tape. That's what they will do.
7/16" is not much error to overcome. Just look it over good to determine where it needs modified before cutting anything. Done this many times when buying used racing axles that weren't ordered for my housing. They really only need to be close. 7/16" is way close.
Hope this saves you a few bucks.
 
Good post above, IMO. As I recall, and in checking my older FSM, the thrust buttons are not nearly deep enough to create 7/16' of space by removing them; this info is just relative to the green bearings, I suspect. I don't think removing the thrust block doable on this but I don't know that for sure. This leaves shortening the axle or getting a different one. The axle splines still need to be measured to be sure that they are long enough to clear the mating splines in the diff.

Question to Von Cramp: Were these the original axle shafts with the axle, and is it just that the diff is new to the axle?
Dumb question on my part (to everyone): What different axle lengths are out there for the 8.75"? Were stock sure-grip axle lengths different than for stock open diffs?

Stuff happens! Don't beat yourself up over it. The only people who never make mistakes are the people who never do anything. Mistakes don't make you bad or dumb; they make you human.
 
nm9stheham said:
Good post above, IMO. As I recall, and in checking my older FSM, the thrust buttons are not nearly deep enough to create 7/16' of space by removing them; this info is just relative to the green bearings, I suspect. I don't think removing the thrust block doable on this but I don't know that for sure. This leaves shortening the axle or getting a different one. The axle splines still need to be measured to be sure that they are long enough to clear the mating splines in the diff.

Question to Von Cramp: Were these the original axle shafts with the axle, and is it just that the diff is new to the axle?
Dumb question on my part (to everyone): What different axle lengths are out there for the 8.75"? Were stock sure-grip axle lengths different than for stock open diffs?

Stuff happens! Don't beat yourself up over it. The only people who never make mistakes are the people who never do anything. Mistakes don't make you bad or dumb; they make you human.
Click to expand...
I am starting to question the length now because I have 4 1/2" bolt pattern axles! Anyone know the length of a stock a body 4" pattern axle?
 
DoctorDiff said:
I guarantee your clutch hub splines and side gear splines are mis-aligned.
Click to expand...
Never expected the great Doctor Diff to find me here! I read another thread here and I know you are right! I just got so many possibilities thrown at me that I ended up making it a lot more confusing than it had to be. I hope you don't think I didn't believe you. I just wasn't sure what to do. Unfortunately the guy who put together the third member already trimmed my axle down. So, now I will have to find another one. I talked to three driveline shops here in town and they all said it was wrong axles or the thrust button. I can't even pick the third member up until Monday now. Really sucks, but I know a little more than I did before about the 8.75 rear.The biggest problem is that I had no idea if I inserted the passenger side axle and rotated it, I would throw the splines off on the driver's side. All I knew is that my axle didn't go into this new third member with a suregrip. I was lost. When I get it back, hopefully the crowbar on axle trick will work.
 
You must log in or register to reply here.
-

Back
Top