68 GTX Rear Axle Issues

[Fireball3553]

I have 68 GTX with a 440-727 that both rear brake drums rub on the backing plates. Is it possible to have the rear axle bearings on the axle too far? How and I resolve the rubbing issue so it doesn't rub the backing plates? The plates are straight. Thanks

 

[mmissile]

Wrong drum and backing plate combo? 2 1/2 and 3" stuff?

 

[PRND21]

How bad do they rub? Would a shim between the drum and the end of the axle work? I wouldn't think .030 to maybe .050 would cause any problems.

 

[Fireball3553]

I just bought some washers to try and see if the space will take care of the issue. Then I could have a spacer made to go behind the rim and up against the axle. Will try that and I'll post an answer here. Thanks for your help.

 

[Fireball3553]

The car was a drag car years ago so I"ll measure the drum and backing plate to make sure they are a set. Thanks

 

[Fireball3553]

I'm still working on the car so I won't finish it till Tuesday. But the washers behind the drum didn't work. I think maybe I have the rubbing sound because the axle wasn't adjusted correctly. There was about 3/16 play on the right side and about 1/8 play on the left. From what a friend told me, there should only be .013 play total. You are suppose to adjust the nut on the axle till it's snug, then back it off 4 notches on the nut. Will try again on Tuesday afternoon. Thanks

 

[AR67GTX]

I'm still working on the car so I won't finish it till Tuesday. But the washers behind the drum didn't work. I think maybe I have the rubbing sound because the axle wasn't adjusted correctly. There was about 3/16 play on the right side and about 1/8 play on the left. From what a friend told me, there should only be .013 play total. You are suppose to adjust the nut on the axle till it's snug, then back it off 4 notches on the nut. Will try again on Tuesday afternoon. Thanks

Yes, the .013 inch play is a good figure. The adjuster should be turned until there is zero play and then backed off until there is around .013 inch play. It's best to measure with a dial indicator. Play of 3/16 inch is way too much and might lead to some strange noise from the bearings and since the tapered bearings are - well tapered, looseness might lead to enough play in and out and up and down, to result in some contact between drum and backing plates and shoes and cause noise. The play figures apply to the original tapered bearings. If it was a race car, someone might have installed the green ball bearings. They don't require adjustment of play (or so I'm told - I don't have them). If you have green bearing and excessive play I'm not sure what the answer is.

 

[PRND21]

If green bearings have excessive play, the bearings are bad or loose on the axle.

 

[oldbee]

Also supposed to bang left shaft couple times to make sure it's seated, then move adjuster on rt.side.