SledgeHammer 2.0

Okay, for those of you who have followed my rear end scraping noise problem... I took it over to a Corvette Specialist. I trailer-ed my car there because the noise of the rotor being hit by the caliper was getting so bad I was afraid to drive it.

When I got it there we pushed it in the shop and the guy there jacked the vehicle up at the center of the rear end, grabbed the P.S. tire and it moved up and down (in and Out) with a pretty good solid thunk, like the wheel bearing isn't tight at all. I told him that stuff was pressed together and I would just about promise the clearances were right.

Anyway, got a call today and the guy is telling me that the trailing arm was moving in and out due to a retainer clip in the rear end that holds the axle being either gone, worn or just bad. He stated that the axle shaft was moving in and out at least a inch. Evidently the bearing for the spindle is set correctly and the axle shaft is causing my problems.

Any of this make sense? I still can't picture how the Rotor could be hitting the caliper because of the axle in the rear end.

Bill Irwin

Proctology calling Doctor Dover, Doctor Ben Dover.

Sorry, could not resist. Bill.

Geek's 65

For those of us who haven't been following along . . . . What year car are you talking about? I have taken a couple 65s, a 67 and 69 trailing arms apart and set them up correctly. The stub axle has a big ole nut on it that holds the whole thing together after you set up the play using the shims. The only way I could think of where the axle shaft moved in and out an inch is if that nut wasn't tight or fell off which means the cotter key wasn't put in or secured and fell out. Never heard of or see a "retaining clip" in the axle set up of a trailing arm.

65 vette dude

I'm no expert, but it sounds like he's talking about the C clips inside the rear. If they break, and the pieces move around in there, they can reap havoc. One inch of in and out movement seems like a lot.

Pilot Dan

Could be a broken or missing C clip or worn stub axle end. If you are really unlucky like I was, a worn elongated differential pin hole in the posi. Either way, if that is where the play is coming from, you will need to pull the center section and remove the cover for a look. I ended up having Gary Ramadei (GTR1999) rebuild my rear. If you have a differential problem, he is the best. Pilot Dan

SledgeHammer 2.0

That's the piece I am talking about. I got an initial quote of around 1500. just to fix the clip. Way more than I thought.







Here is my original "drama filled" post.

http://forums.corvetteforum.com/c1-a...sion-bump.html

65 vette dude

Sound's real high to me, and I bet the final bill will be even higher than that. I would contact Gary Ramadei about a rebuild......gary.ramadei@radiall.com

mechron

everybody above is correct about the C clips. what actually happens with C2s and C3s due to the design of the rear suspension is that the differential yokes are pushed inward and wear aginst spider gear cross shaft (which is harder). eventually the yokes wear enough to where the y are worn to the C clip groove, then the C clips simply fall off.
this is way more common than you may think. i have done 100s since the 70s. C3s seem more suseptable to this than C2s, wether it was due to increased weight or just poorer metalurgy in the 70s i have no idea. on C3s i have seen this happen within as little as 60-70 thousand miles. 1 inch at the yoke is impossible, 1inch at the top of the tire is about right in and out for a yoke with a dropped C clip.

TheSaint

My first thoughst to

TheSaint

Deleted

wombvette

Yes, but, a missing C clip will cause no noise, and no real future problems. Grinding a C clip up in the gear is possible and could cause damage to a gear, but it is very rare. I find hundreds of clips in the bottom of rear housings, some whole and some not, and the rear is operating perfectly. This certainly will not cause the rotor to hit the caliper. That would only be possible if the rotor is moving relative to the bearing. Otherwise it is held solid and cant contact the caliper.

Geek's 65

I agree. Any issue in the pumpkin won't cause the rotor to contact the caliper.

Kensmith

When I first got my 65 coupe, I took it to a local shop to be checked out. They found that they could move the trailing arm in and out also and this was due to normal wear. Unfortunately for me they also found the 4.11 posi case to have a very small fracture so I went with buying a re-built rear end as repairs were more than the re-built. After it was replaced there was still a screeching noise coming from the r-rear. Well, come to find out there was also a bad wheel bearing. So I got a re-built trailing arm VS replacing the frozen bearing. Then came the missing E-brake shoes. L-rear had them, r-rear didn't. Always full of surprises. Sounds like you do need to have the rear rebuilt for bearings, yokes etc. Not sure how the caliper can touch the rotor though unless it is warped.

Mike Ward

Wayne is right. The excessive play in the yoke has nothing to do with the rotor hitting the caliper.

Can't your 'shop' see or hear that problem?

kimo1965

[QUOTE=Pugly;1573889450]That's the piece I am talking about. I got an initial quote of around 1500. just to fix the clip. Way more than I thought.


That's a RIDICULOUSLY high price if it is only "just to fix the clip" as you say above! I had one break one time. I simply pulled the cover off the rear end and replaced the clip. Took less than an hour and solved the problem. Jim

Kensmith

[QUOTE=kimo1965;1573896815]I'm sure that is not for the clip but a complete re-build with bearings, clutches, tolerances set, etc etc etc.

SledgeHammer 2.0

No it was for the Axle stub that sticks out of the housing.... Axle and Clip, Labor and fluid.

While I may not agree with the price, I don't think the guy is trying to rip me off or anything. I went to his shop with what I believed to be more than one problem, he started on the inside and once that is fixed will check on other problems. My problem is I can't afford to start off at $1500.00 and wind up at 3K plus. I am sure once the in and out problem is fixed, then the rotor problem will still be there and that will be more expense.

The trailing arms have new bearings in them. I am just going to have to pick up my car and either store it or buy me a book and rebuild the whole rear myself. I have rebuilt plenty of differentials in Camaro's Mustang"s etc. Just have very little experience with the whole half shaft thing. Most new cars with I.R.S. have regular style control arms (upper and lower) in the rear with CV axles.

If you think about it, That clip has to be very important. Other than the front trailing arm Rubber Bushing what really controls how much the top of the tire could travel in an in and out motion? The strut holds the bottom in place, but there is nothing on the top.

Hitch

[QUOTE=kimo1965;1573896815]Can you explain to me how you dropped the diff and pulled the cover in less than an hour on a midyear? There are a few bolts that are blocked by the crossmember..

As for the grinding noise and the rotor hitting the diff has nothing to do with this problem. It sounds like you need another shop to investigate this problem because the shop you have it at is only interested in your $$$$$

Dave

Geek's 65

Clip has zero to do with your tire moving in and out AND the rotor hitting the caliper. Lateral tire movement where the rotor could hit the caliper is set by the inner and outer bearing setup in the trailing arm. NOTHING else. If tire is moving in and out because the half shafts are moving in and out, then so is the complete trailing arm assembly. Ergo the rotor and the caliper are both moving in and out exactly the same because they are part of that assembly.

Your shop may be right - the clip missing in the pumpkin and letting the half shafts move is wrong and needs fixing. But it isn't causing what you first took the car to them for. If the rotor is hitting the caliper then there is something in the trailing arm/wheel assembly that is messed up.

Mike Ward

Not correct. The rear suspension geometry ensures that the yoke is pushed INWARDS at all times with at least 300lbs load. This load increases during cornering up to a lateral load of 1.3G, or if the car is lifted off the ground. You can take the clips off and throw them away and it will make NO difference to the handling. Many have in fact. Many more have driven their cars for years without knowing about the missing clips with no negative effects, including you.

I see many people have tried to offer advice steering you back to the original problem of the rotor hitting the caliper. How about focusing on that?