wombvette

It is amazing that, given all of the reasons for not slip fitting the axle bearings, there are, so many posts touting this dangerous practice. I feel like I am whipping a dead horse, but I will try one more time. I am not preaching doom and gloom here. If the unit is maintained regularly, you probably will not have a catastrophic failure that would cause property damage or injury, but you will likely have wear problems that cost more than the savings realized. You do however increase the chances of catastrophic failure and I personally would not take that chance. Some seem to disregard all of the stated reasons for not slip fitting the bearings stated in the previous thread. They claim that slip fit is no more dangerous, that the wheel is not likely to come off, that the engineering is antiquated and faulty. There were some very good arguments against it, that were blown off, including one axle failure that could easily resulted in the loss of a wheel. I have offered my 30 years of experience, but have been casts as a professional repairer trying to scare the public into taking their car to a professional for an expensive fix. I personally don't care if you do the service yourself or you hire a professional. I do, however, care for your safety and those on the road with you. Here are a few examples of axle failures. http://www.members.aol.com/wombvette/AxleFail

The axle on the left was slip fit and the bearing failed. It turned within the inner race and wore down until it literally cut the axle in two. The axle on the right got red hot and melted before it twisted off. Both of these resulted in the loss of axle and wheel. Luckily in each case the final failure occurred at low speeds.
http://www.members.aol.com/wombvette/AxleFail2

This axle shows evidence of the bearing beginning to turn on the axle shaft. If you slip fit your bearings this turning is more likely and will progress until there is a great amount wear. This will make proper bearing setup impossible and more and more looseness will be evident. Eventually the axle will become so worn that the bearing play will get completely out of limits and no adjustment will restore it. It will destroy the bearings and the axles. If nothing else your slip fits will cost you several hundred dollars. If you use the spacer and shims and properly setup the bearings this may not manifest itself so quickly, so be sure to use them. Another reason to use the shims and proper torque is to minimize torsional deflection in the axle shaft. Without the solid setup it is much easier to warp a shaft and cause bearing and brake problems. I have even seen shafts bent in a panic stop.

I seldom see a properly set up, pressed fitted assembly, that has grease, fail. I do see many that were improperly assembled and set up fail. The most common failures that I see are, no grease, no spacers and shims.

All I am asking is that you consider these things, and ask yourself, Is it worth the risk?


[Modified by wombvette, 1:44 AM 5/25/2004]


[Modified by wombvette, 1:50 AM 5/25/2004]

turtlevette

you can have those same failures with the factory recommended setup. I can show you 2 of my axles that were almost cut in half.

I now have an easily maintainable setup that will be taken apart and greased more often versus a setup that is so hard to maintain that people just let them fail insead of paying many hundred of dollars to have it taken apart and greased. Because of this fact i can make a good case that the factory setup is more dangerous. How many people are driving around with dried out grease primed for failure the first time they take a road trip?

I believe its impossible to press the axle out with the trailing arm in the car. Removing the trailing arm really makes it a major job. I like to take my car on long trips and i don't feel like being stranded for a week because nobody knows how to work on these things.

I spent a week driving up in Newfoundland CA and shortly after returning home one side failed. I don't think anyone owns a corvette up there much less anyone that can work on one. I want an easily maintainable unit that i can fix and get back on the road in reasonable time.

P.S. I have 24 years of experience working on my C3 corvette


[Modified by turtlevette, 5:47 PM 5/25/2004]

NHvette

I agree with most of both your posts, but ....

I'll pick on the issues I disagree with.

Bent an axle in a panic stop ... I don't think so ... unless the panic stop sent the car sideways into a granite curb.

The trailing arm does not have to come out for pressing ... just the bearing carrier.
Also, Wombvette is stressing the idea to use the spacer/shim WITH the slip fit
bearings. I think most everyone agrees with this. The shims are very easy to
get perfect, if the bearings are slip-fit.

:seeya

VETDRMS

Thanks for the information... :lurk:

:cheers:

wombvette

NHvette, I know it sounds impossible, but I have seen it. It wasnt bent to the extent that you could tell by looking at it, but the flange was out enough to cause brake failure. I wouldnt say it if it wasnt true.

Turtle, I know that there is no use arguing with you. I will never convince you, but maybe I will convince someone else. And it isnt that I want them to come into my shop for an expensive repair. As a matter of fact, if they come into my shop with slip fits, it will cost considerably more. There are numerous ways to get the axles out with the trailing arms still in the car. Seems like you would have learned one or two in your 24 years experience. I can have the axles out in no more than 15 minutes a side. the time consuming part is in the setup of the bearings and other necessary proceedures. That needs to be done slip fit or not. :seeya

turtlevette

i have found that the trailing arm bolts have to be cut with a sallsall every time. I am at a loss to figure out how to get the bearing assembly out. You just can't get at the nuts with all the e-brake hardware in place.

Let me ask you this. Where do you stand on wheel spacers and adapters. I did not see you present an opinion in either of those threads.

Paul Borowski

:lurk:

72rdstr

:lurk:

lbell101

It's easier to take out the e-brakes than to remove the whole trailing arm (unless they are new and easy to remove or it's so bad it must be replaced). Or sometimes you can remove the spindle first (especially if someone slip fitted them) and then the nuts are right there.

Larry

wombvette

Sorry, I never read those threads. Personally I would never use any kind of spacer or adaptor. But I dont go in for much aftermarket stuff. I think that they are a risk unless engineered for the specific application. I had a customer bring me a car a few months ago that had a new set of cragars. He had just had tires put on it. I took it out for a quick test drive and returned promply as it was making a lot of noise. The tire store had failed to replace the spacers. Well it had knocked both calipers off the rear.

BTW, You do not have to take any of that stuff off the remove the axle and bearings. Just the caliper, half shaft outer joint, and the yoke.

turtlevette

Good I agree. At least you are being consistant in your philosophy.

That does assume that you have a tool to press the axle shaft out? I have heard these tools don't always work for tight press fits and the trailing arm has to be removed and put in a press. I have heard of storys of people having to put so much force that they bend their press.

Just too much trouble.

Van Steel

Here are some slip fits that people thought they set up right. You gotta be real careful and know what your doing.

GDaina

Good write up Womb...when I was doing my 68, I thought about slip fit, decided...Nah....sent the units to Bairs, requested they use synthetic grease.

You and I haven't seen eye to eye on some issues on the NCRS board, but I'm with you on the slip fits.


[Modified by GDaina, 9:28 AM 5/26/2004]

turtlevette

its good to see that old rivals can unite against me. You see i AM doing something positive. :lol:

norvalwilhelm

Setting up rear bearings is not Brain Surgury and anyone that knows what should be done and has a few simple tools can do the job.
Sure there are lots of people out there that really don't have a clue but alot of us do know how to set up bearings just as well as any company.
Tom's advertises slip fit bearings for easy maintenance and I thought he was highly respected for his products.
While I don't agree with leaving the spacer out I still believe in inner slip fit bearings.
The original press fit was used with drum brakes where a broken axle would walk out the side of the car. Our disc brakes prevent this in case of a break.
I have axles at home in the cupboard that are twisted off due to slicks and they look alot like that.
If a bearing starts to spin on the inner race it galls badly and eventually would seize on the shaft , just like a press fit and then start spinning like a normal bearing but cause a vibration. I can't see it totally wearing the axle down like that pictured.
Once again I do not agree with removing the inner spacer but it was done to my car and drove like that for years before I bought and discovered it.
Turtle vet is just trying something that has beeen brought up on the forum repeatable in the past. Our front bearings get away with it so why not the back???
Hotrodding is about trying something different, it is his pocketbook that suffers if the bearing lets go and I don't think one minute it is fine and the next the wheels take off in different directions.
He is trying something that we all have thought about at one time or another.
Let him experiment and keep us posted on the results.
Turtlevet you do live far from me?? Right ???? :lol: :lol: :lol:

turtlevette

do i not get invited to your house now? :sad:

Paul Borowski

The front wheel is just a "coaster" wheel. Not a driven spindle. The front spindle is stationary, where a rear spindle is spinning "in the bearing". There have to be much greater forces on the rear bearings with a spinning shaft in it and and axle shaft driving that "spinning" axle. Just my $.02 :cheers:

Barry's70LT1

Just to expand on front vs rear bearings.
My observations.
We all know the front setup works, slip fit and all.

With the rear set up as a slip fit, many say this is doomed to fail.
However, in most cases it is not the same "slip" fit as the front.

There is a sleeve and 100+ ft lbs of force keeping the inner races in place.

It only seems logical that there would have to be some kind of major bearing failure to over come the torqued inner races.
If this happened, I suspect you will be in trouble, slip fit or not.

As for outright breaking of the spindle, as Norval stated, the caliper should prevent the wheel from leaving the scene.

I don't agree with slip fit and no spacer. The absence of the inner races being pinned at 100+ lbs of torque could promote the races spinning on the axle.

Just my thoughts.
Thanks, Barry

moosie982

As for outright breaking of the spindle, as Norval stated, the caliper should prevent the wheel from leaving the scene.

Hi, The first time the bearings went on the '80 it DID take the caliper with it, broke off both mounting ears, along with slicing the tire, now,,,,,,,,the second ex-wife was driving the car at the time so maybe that had a lot to do with the caliper breaking,,,,,,,,,,,she didnt have the sense to stop when it started making death noises I betcha, now here we are fixing it again and thinking hard about making it slip fit again, need to get anew spindle this time. Peace,,,,,,,,,,,,Craig :seeya

NHvette

Keep looking in the forum for my vette-together later this summer.
We had a nice pig roast last year ... haven't decided on food for this year.
Everyone's invited. C1 to C6. Yes - even people with modified C3s. :lol:
:seeya