The total tolerance is .0005". And, yes, it is ridiculous. I'm sure the vehicle would have no issue with an end play of .003". But, I don't write the manual and I haven't tested it at .003" with a sufficient data base to make the conclusion.

My jet engine balancing tooling has tolerances that are .0004" in certain cases...........and we pay dearly for that privilege.

I bought that dial indicator and the magnetic base from harbor freight.
they are listed as $9.99 each on line, but listed $14.99 each in the store.

I asked about the price difference when in the store, and the guy let me have them for the on line price.

I didn`t pay attention when I looked at the dial indicator, there is no metric scale, just SAE.

I just read through all this, and this is literally splitting hairs. I would, but my eye sight isn`t that good any more



Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

dont say that too loud..............dont want Stuttgart to hear....


I have done both front and rear by feel, and I have had to go back and re-do both. maybe my feel is not very good, but it is worth the $20-$30 investment in cheepo tools(if this is all you'll use them for, they'll do) to get it right.

^ both times i did get over 10K miles service, but they still failed prematurely, IMO

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.

It's one thing to debate whether the spec should be 0.0005" or 0.0006" or 0.001." But the real debate should involve how close one can come to the spec when using "feel" in lieu of an indicator. My money says you will miss the spec substantially almost every time when going be feel.

Plenty of aircraft use wheel bearings that are exactly the same as used in automobiles.

The spec for the W123 is 0.01 - 0.02mm. In round figures, that translates to 0.0004 - 0.0008."

Thanks......now translate that into number of lines for him.......

That is true, unless he has a tenths graduated indicator (tenths in machine talk is ten thousandths), then .0004 to .0008 will not be able to be read. I like to think my MB is aircraft quality, and I apologize to Stutgart for saying that they arent aircraft quality....lol. I also know that aircraft have many bearings that are only automotive quality, mostly like linkages, cargo parts, and doors.
But either way, you can only make roller for bearing within .0001 to .0002, any more precise and they can only be measured with a CMM, or a laser device...lol which I am sure are made, for NASA, and the airforce. I could for sure seeing the need there for tolerances in the hundred thousandth or millionth range... which I will have no part in making.... even with ten thousandths, what you measure on a micrometer, is speculative. Becuase the next guy might apply more or less pressure, and a different mic, might be off by .0001, and temperture is a HUGE deal when you deal in .0001, or .00005
Im off my soapbox now...lol

As I recall, that nut has a 1mm thread pitch, meaning a 10 degree backoff calculates out to a ~0.001" distance. However, there are so many sources of error that you probably can't say much of anything about whether that equates to ~0.001" of play.

As Brian also said, its better to be too loose than too tight, but whether this method will get you there in any particular attempt is anybody's guess.

In this day and age, how can we even be sure those bearings are manufactured to tight enough tolerances, and with tight enough quality control, to support the speced play?

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'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

That is exactly correct. I guess what it boils down to, is that, the tolerance that MB calls out for, is something that may not be achievable in this day and age. Not every man and woman in this forum is a person who is familiar with dial indicators, tenths tolerances, or has the time to be. You cant look down on these folks for not having this knowledge or ability either. True, a person might say "Well, this type of person needs to take their car to a dealer or good quality repair shop, and forgo the DIY venture". But who says that this shop will adhere to the .0005 tolerance? Or even use a dial indicator themselves? The moral of this story is, quality is something that seems to be dying off. In all aspects of life. I say, to the guy who is looking for the preload tool, or inidicator. Go ahead and get the indicator, and try to get .0005, to .001 of end play. The closest that you can get it, is probably going to be close enough. I am sure a dealer, or shop would probably do the same. I would not be surprised to take it to the dealer, get it home, check it yourself and see that is has .0015 or .002 of endplay, or worse.... none!

since were on the topic, i was wondering if you need the calipers off to correctly measure the clearance. i had to drop my car off the stands and move it around while harbor freight sent me the part they forgot to. i just did the bearings by feel and was going to set them again before my car hits the road. i am very familiar with dial indicators but not for wheel bearings.

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If the midrange of the correct specification is selected, an error of plus/minus 33% is still within tolerance.

No. But the brake pads should be pushed away from the rotor.

It might be within tolerance..........might not..........because you failed to take the accuracy of the gauge into account. That's quite critical...........you know.

Incorrect. I allowed for a measurement error of plus/minus 33%.

The accuracy of the gauge is probably not better than .0003". A measuring error on the part of the technician of +/- 33% is perfectly reasonable due to the very tight tolerance.

Combine the measuring error and the error from the gauge and you cannot be certain that you're within tolerance............not that it matters..........