Has anyone on here ever had a bent spindle? I have extreem runout on my DR rotor only and within tolorance on the PR rotor.

 

rear spindle on c4 is just a passenger in the bearing assy...when putting c5 front rotors on mine, found one practicaly new GM bearing assy there was ''high max'' runout which translated to excess runout with the larger c5 rotor...marked the high point of the bearing assy and took it to local machine shop who chucked it up ''crooked'' in a lathe to match the high side and ''faced'' it off, final result under o.001'' installed

 

Well, when I look at the DR axle spinning, it has a wobble to it...not as severe as the rotor....I am guessing its because it is farther away from the pivit point(bearing assembly). I am thinking, rather hoping, that the spindle is what is causing the shaft to wobble. Of course, I dont know which would be cheaper to replace, a spindle or axle shaft...maybe both

 

What is a "DR rotor"? A "PR rotor"? What is an axle shaft, in a C4? The half shaft (if that is supposed to be the axle shaft) would have nothing to do with brake rotor run out, if that is what you are talking about.

RACE ON!!!

 

I'm pretty sure he means 'drivers rear' rotor and 'passenger rear' rotor. I can't read his mind, but he is talking about rotor run out and axle shafts, so that points almost inextricably to the rear rotors.

If you look in a FSM (Field Service Manual), you'll see that what most people refer to on here as a 'half shaft' is called an axle shaft by General Motors. I agree that the shaft wouldn't have anything to do with rotor run out, but his terminology is correct as per my 1991 FSM. You can get an FSM for your car from www.helminc.com.

I don't see anyway that a bent spindle or axle shaft could cause the rotor to wobble, but a bent/tweaked/worn out wheel bearing/hub assmebly could cause your problems.

 

DR=Driver's Rear rotor
PR=Passenger Rear rotor
Axle Shaft=Half Shaft

Sorry for the lingo...now that you know what I am talking about... I will explain.
I came in to fix a drink...this is my first chevy...one of chevrolet's high end sprorts cars, and is now driving me to drink! I have always been a Ford man...saying that, I am not impressed as of yet...except for the power.
To the problem at hand, I have had a sqeeking---combination---clicking in the drivers rear since I bought the vehicle a little over a month now...thought it might be a bearing, but I noticed when I wash the car, particularly the wheels, the noise went away for a while...maybe after ten minutes or so of driving. That led me to believe it had something to do with the brakes. With the wheel off, blocked up, I ran the car at idle speed in drive and there is severe rotor runout and sqeeking at the same interval as the wobble. Such a severe wobble that I started looking at the half shaft...it had a little wobble to it also, but not as severe...but enough that I know it causes a problem in balance and vibration. As I am dismantling the wheel assemblies, what I am finding is leading me to believe it is a bent spindle. I removed both wheel speed sensors. Compared to the side that has no runout and no noise, the sensor on the troubled side has been impacted, knocking the piece that protrudes from the sensor, off flush with the sensor. The good side has a piece that protrudes(about the size and shape of a standard slot screwdriver), except inverted(an outie instead of an innie)...logical reasoning leads me to believe that this is the pick up for the ring gear for the ABS. In any event, a warped spindle, if bad enough, and I am sure the clearance is pretty close...and I think if the spindle is warped bad enough, the ring gear would come into contact with the wheel speed sensor...probably the reason why my ABS light comes on. I am all ears for any additional points of veiw.

Race on!!!!

 

Good guess. I thought maybe "passenger" and "drivers", but I usually see left and right, plus I never made the connection between "R" and rear. Also, guessing that the "axle shaft" night be what we commonly call the half shaft, I was still unsure, because no way can the "axle shaft" contribute to brake rotor run out.


"
I'll have to check out that link and see if I can find a "FSM (Field Service Manual)". All I have is a Factory Service Manual. The first reference I found in my book made reference to the "wheel drive shaft". My 1984 - 1990 parts book lists it as, "Shaft, RR Wheel, Dr UJT.

The disparity and uncertainty of terms didn't make things totally clear, which is why I asked. It seems every time I make assumptions, I get my head handed to me on a platter, No different, I guess, than if I don't.

RACE ON!!!

 

clicking/ squeaking/ vibration -- each alone is a classic sign of a universal joint (six of em under a vette vs two on lesser machines) that is dry (no grease inside) and rusty, and you have all three symptoms -- kinda sounds like you need a new u-joint...''wobble'' that you report in a half-shaft can be a toasted u-joint showing off.
often with the car up off the ground, to ''unload'' the shaft, you can grab the shaft near a bad u-joint , try to rotate the shaft to/fro and see a small ''slop'' or movement of the u-joint trunion in the outer housing...if you can't see/feel movement, gotta pull the shafts off to check -- not a total loss with finding joints that are ok as they prolly are in need of some new grease before re-install for the next 100k miles...not a bad idea to replace all if one is bad, great for peace of mind, but many times it will be never before another u-joint fails after the first one, and a ''squeak'' usually gives several hundred miles warning before demanding attention.

brake rotor run-out is another separate issue.

fwiw: just looked at a half dozen different MY/ model ''service manuals'' and NONE have the ''F'' word on the front, just ''service manual'', propose that we just call 'em SM's in the future.

 

No offense intended, just ribbing you a bit, all in good fun. Sorry if I upset you. Good catch on the 'Factory' VS 'Field' error I made.

I'll be out your way skiing sometime this winter. I'll let you know when I plan to be there, and if you are so inclined I'd love to buy us a round of drinks.

 

Actually, my thoughts were the same. Less than a week after purchasing this vehicle, I noticed a "clunk" when i would shift from reverse to drive....telltale signs of a bad u-joint or bad tranny mount, not to mention the squeeking and clicking....so I said the hell with it and replaced all 6 of them. By the time I had gotten all 3 shafts out and inspected them, noticed they had already been replaced(aftermarket joints with grease fittings in the bearing cups...definately not OEM), all were tight, but I replaced them anyways since I already bought the parts and the shafts were already out! Didn't do one ounce of good. Still had all the same problems. I know where the squeek/clicking is coming from. I guess I am hoping that the clunk I am hearing when I shift from R to D is the crappy rear brakes that dont even bite. I could have a hundred lbs of pressure on the brake pedal, and if I am in sandy soil when I do it, I can see my back tire kick out dirt when I shift from R to D. It never does it when I shift into R though. As of yet, I can find no tranny mount....and if it were a motor mount, I believe the engine would be hitting the underside of the hood...but I could be mistaken. As for the crappy rear brakes, I found the thread 'hard brake pedal solution...finally!'.....out of the 200+ posts, the only solution I found was to take it to somebody else to fix! OK, now that I have eliminated the u-joints, do you have any other advise?

 

Which is better? The aftermarket Helms or the actual dealer's Service Dept. manual? Big blue binder type with the chevrolet logo, about 600 pages, got it off ebay straight from a dealer's list of discontinued items, just for my year, 1986

 

Helm manual = FSM.

To the best of my knowledge, Helm is the printer for all the Factory Service Manuals. The only difference might be in if/how the drawings are colored.

 

I am still trying to picture a bent/tweaked bearing assembly....and how likely it would be the culprit.there is absolutely no slop in the bearing when I try to move the wheel back and forth and up and down.

 

Any manual, Chilton's, Haynes, etc, can be called a "Service Manual". The term "Service Manual" is generic. "Factory" makes reference to the manual that is commissioned by the Chevrolet factory. I'm thinking you "prolly" (sic) knew that. All of my FSMs produced by Helm Inc. for GM. are titled either "Shop Manual" or "Service Manual", and have the car line logo and/or the GM logo. Our (my) adding "F" for factory separates the wannabes from the genuine article.

RACE ON!!!

 

I thought (hoped) it was all in good fun. You gave me an opportunity with the "F" word, so I jumped on it.



That sounds like fun. Let me know your plans. It's too bad we never got together when you lived 3 miles away.

RACE ON!!!

 

Chevrolet hires, commissions, Helm Inc. to produce their service manual for them. Either ought to be produced by Helms and contain pretty much the same stuff. The manuals the general public can buy at www.helminc.com are single year issues, also.



I cannot imagine how a bent spindle could cause run out in the rotor. A bent spindle, hard enough to imagine, shouldn't ever cause rotor run out. The rotor mounts to the hub (bearing assembly). Any run out would almost have to be a non-parallel rotor mounting surface on either the hub or the rotor itself, a warped rotor, or foreign material between the rotor and the hub.

RACE ON!!!

 

Hey guys, thanks for all your help! I believe I finally found the culprit. I am posting a few links to some pics I took after I got the hub off finally....and wow...ya'll were right on! The hub where the bearing is inside is cracked half way around the whole hub...only half way, so it looks a little distorted to one side. Would this also cause the ring gear in on the spindle to come in contact with the wheel speed sensor causing the tip to be broke off, as well as make the "half shaft" wobble? I don't know if these links will work...but thanks a lot for everyones help!

http://i116.photobucket.com/albums/o...e/IMG_2603.jpg
http://i116.photobucket.com/albums/o...e/IMG_2602.jpg

 

This is mine:

 

Well, everything is back together....crossed my fingers....new bearing, new u-joints, rotors turned, but I still have a slight wobble in the halfshaft and the newly turned rotor has some runout on it. When in gear, wheels off and lugnuts on, half the rotor rubs the outboard pad. The new bearing took out 95% of the wobble, but there is still a little left. Boy, I am just **** when it comes to things like this. I have another spindle on order off ebay, and debating wheter or not to buy another halfshaft or take it to a local shop here and see if the can either straighten it or make me a new one....any ideas?