Allen_396

My '69 is making a rubbing / scraping noise intermittantly from the rear wheel(s). I tried jacking it up to spin and check, but it just doesn't seem like a good idea to have the wheels hanging down like that.

Where is the best and safest place to support the back end so I can spin the wheels and not have them and the suspension just hanging there?

Thanks!

hammadown

put the floor jack under the outer leaf spring to trailing arm bolt

Hammadown

1955pirate

Does the rubbing/scraping noise seem to be more prevalent when making a slow or accelerating turn? Sounds as you describe can sometimes be the posi telling you it would like some new lube.

elke_10

check the inside of the tires specially if you got 255's on as the e-brake line may be rubbing the tire

Allen_396

Thanks for the suggestions. I only have one floor jack. Where would one put jack stands to get the back end off the ground so I could have it in neutral and spin the tires and not have the suspension just hanging?

It sounds more like actual rubbing, rather than something from the posi rear. But I don't know for sure yet.

Lon Wayne

When did you last change out the rear end fluid .Two bottles of posi additive & fill with chevy lube $9.99 on the additive and are you sitting down? and the fill two bottles $16.00ea. "ouch" I walked around McDormans holding my rear end all day $84.80 to swap out the rear end fluid.

The clutches are grabbing I know its hard to belive that any fluid you add can make a noise quit but Ill buy your lunch if the clutches are grabbing and the rear end lube doesnt fix it. now wheel bearing thats another thing ( but it makes that noise at a different time)

toolman1981

Could be the emergency brake pads that are located inside the rotor.

They act just like a drum brake to hold the car.

The springs are notorious for breaking and allowing the shoe to ride on the inside e-brake surface.

That could explain the rubbing sound.

1955pirate

Yeah, expensive, isn't it? I think I payed $54 bucks for the two bottles of lube and one bottle of friction modifier. Fortunately, I have a good buddy in the business and he let me use one of his lifts and I did the job myself. Had to pump out the old lube from the rear end....at least on my '69.

It did stop the noise I was hearing. The previous owner had no record of the rear end service so I have no idea how long it had gone.

Allen_396

I changed out the rear end fluid a couple of years ago, and then promptly leaked it out over time due to a bad pinion seal.

It has a new seal and new fluid.

Where would one put jack stands to get the back end off the ground so I could have it in neutral and spin the tires and not have the suspension just hanging?

Lon Wayne

Allen, I use two hydraulic jacks and two sissor jacks and two stand jacks. I un-hook the battery open the doors put a towel in the jambs so they dont close .Then I use boards on the top of my hyd. jack I lift up the sides A little bit at A time.(my 75 has a big metal angle at the back of the frame) its A pain and more than I need to do but Ive seen where jacks have left dents in the frame and I dont have any now and dont want any. Im putting in new yokes seals and fluid should be driving it this weekend.I also have A sissor jack under the diff.and a sissor jack under each side under the shock mount +the stand jacks holding the whole rear end of the car up .I hope any of this makes sence to you .

tonak

I am curious about the answer also. I think Allen is getting at the rear wheels dangling is not the way to rotate rear wheels. They need to be up off the ground, and lifted to somewhat the normal driving height if that makes sense.

Allen_396

Exactly! I don't want the suspension dangling down due to not knowing what sort of unnatural bind it might put on the U-joints when I try to spin the wheels.

I have one floor jack and a few little jack stands. It didn't seem safe to support it on that big bolt back there on each side. So, I was wondering where to support the back end so the suspension is like it was on the ground, but so I can spin the tire or take it off and find the source of the rubbing.

onaqwst

see if your bump stop plates on the t-arms are bent down and catching the ujoints... i had that issue

GD70

The jack stands should be positioned a few inches in front of the kick ups. Then use the floor jack under the leaf spring near the bolt, but put a wood block between the jack & spring so there's no metal to metal contact. Raise the wheel up to almost the normal position.