jeff70vette

I would like to stir up some memories from an old debate I once saw posted on the forum a number of years ago ie: slip fit versus factory press fit rear wheel bearing assembly.

I know I'll be doing bearings soon and.......
I am willing to live with the safety concerns brought up by several forum member in exchange for the ability to service and monitor the hub/bearings.

I know there are several members of this forum who have converted to this setup so.......
I was wondering if anyone had specific information on preforming the conversion especially:

1) How does one convert to slip fit setup. What (if any) machining is required, and where does one get the specs. I have machine shop so any turning/machining shouldn't be a problem.

2) What is the preload/setup procedure required.

Thanks,
Jeff

GTR1999

I set mine up using a press fit like the factory did. I was told the early 63 cars had a slip fit and had problems so GM went with a press fit. You are correct there are several here who have rebuilt them with a slip fit for ease in future maintenance. If properly setup then they should go many thousands of miles without need for greasing. To correctly setup for a slip/snug fit you would have to set them up in a lathe and polish them, stopping to "Mike" them for the ID of the bearing. The assembly procedure would be the same and the end play would be the same around .001". The spindle nuts are torqued to 100 ft/lbs. I would really think about the way you want to go before you start polishing the spindles.
Good Luck,
Gary


[Modified by gtr1999, 4:56 PM 2/21/2003]

Ken73

What boggles me is that the front bearings are essentially "slip fit" as they "slip" over the front spindle - and yet they don't have problems? What makes the rears so much different?

Van Steel

What makes the rear spindle so importment not to be a slip fit is that the run out on the rotor, to high of a run out can, cause you to have no brake pedal.
If The assembly is not set up correcty (end play) will cause the spindle to move and give you a bad run out. Spindle, Caliper mounting bracket, bearing support, & Rotor have to be put in giges to check for straightenss. If the assemblies are built correctly you should not have to redo the assembly at all. We warranty them for 5 years with unlimted miles. As far as I know we have never see a 63 with slip fit spindle and I build over 200 plus assemblies a month and build them for Corvette warehouse and chevy dealers. Check me out on the web http://www.vansteel.com

norvalwilhelm

I run slip fit bearings and Tom's advertise them. A slip fit is only on the inner wheel bearing and not the outer. This makes assembly and dismantaling very easy. To make a slip fit axle just chuck it in the lathe, put a center in the other end and polish with emery paper until the inner bearing slides on with just a slight drag.
I take my axles out once a winter for routine inspection and found last winter that I had twisted the splines. I can remove either axle in a few minutes with just a tap from a rubber malate.
In my case I made both the inner and out bearing a slip fit because my center shim is a fixed machined piece and my out flange is also flanged. But both my bearings slide on with only finger pressure and after 2 years and 2 inspections they have never spun.
In your case polish the inner bearing with a pressed outer which doesn't effect diassembly. Check all clearnaces without grease or a seal installed .
This is my home designed and home built axles as my answer to twisted splines. They are 4140 heat treated to 47RC and 80% larger then stock. You can see the fixed machined center spacer with large bearings that fall on with both the flange and inner 1/2 shaft flange removable. These do not break or twist.

GTR1999

Norval- very impressive machine work you did. Did you run those on a CNC or use an index head for the splines?

Van steel - I would have to research the books I have, but I believe someone here or on the NCRS board stated the early 63's were a slip fit. Seems we lost a few of the history knowing guys here lately that could have answered this question.

Gary

Ken73

That's just it - why is the front hub/spindle any different? The bearings are slip fit on the front - and there's not a runout problem there.

Correct - what we're talking about is making the bearings slip over the spindle so they don't have to be pressed on. They might still require some force to put them on, but not a large (read: expensive) shop press. This cuts assembly time and the required tools - you wouldn't need the fancy setup tool, as you could simply push out the bearing rather than having to press it in/out each time.

norvalwilhelm

Ken73. I just said the same thing. It will NOT effect rotor run out if the bearings are slip fit or not. Bearing maintenace is easy if the inner bearing just pops off with a rubber hammer blow. Tom's advertises slip fit bearing for easy maintenance. Wouldn't it be nice if everything on our cars was easy to remove and replace? Like stock cars they can change everything in minutes. It can be if you take the time to make things easier to fit and slip fit bearings is one of them. The only problem you might encounter is the spacer is not fixed to the axles so the outer pressed wheel bearing and the 100 fT nut is what's keeping the inner bearing from spinning on the shaft.
I would go for the slip fit inner bearing, not outer just inners.
I have gone for both slip fit but my spacers are machined into the axle so the bearing shoulder against a fixed spacer.

jeff70vette

Thanks for the replies. The more I think about it the more convinced I am to convert to slip fit.

Norval- I really like what you've built for axles- obviously you have a few ponies in that thing to warrant the work involved.

Now my next question......can I take my existing unit (stock-press fit) apart just by hydraulically pressing the axle thru the bearing/hub assembly. I always read what a pain it is, but I'm not sure why. I should just be able to press it thru, right?

norvalwilhelm

You can press the axle out but it is a pain removing the hub assembly and putting it in a press. If it wasn't for the press fit inner bearing the whole assemble would fall apart in your hands after removing the inner flange nut.
Remember if you remove the inner flange, the caliper and rotor and the 4 nuts behind the axle flange the whole assembly comes out of the trailing arm making it alot easier then removing the whole trailing arm. Here again if you have replaced the front trailing arm bushing and shims with stainless parts and kept them greased everything would come out easy.
As for cutting the splines in my homemade axles my son did that part for me. Where he works they have a sofisticated? spline machine that can cut any automotive spline both inner and outer. Cost me a case of beer.