I'll ask you guys & get your opinion. On my 1966 Ford LTD, when I get up to around 60 MPH, I've got a vibration that acts just like a tire or wheel out of balance on the drivers front. I recently replaced all four tires (w/ balance) & it's still there. I swapped left front with right rear. Still there. I took it to a shop near me that does brakes & alignment, etc. I trust these guys & they feel the problem is a bent p***enger side rear axle. They lifted & spun each side rear wheel on the car & said they got a noticeable bounce on the left rear. I don't feel anything from the rear when I'm driving it, just the vibration/ bounce on the drivers front. Have any of you run into a situation like this? BTW- the rear end is a Ford 9".
What did they say exactly? an axle is either bent or not. It should not "seem to be bent"' Take the wheel and drum off and set up an indicator. A dial indicator is nice to have and is very accurate, but a simple homemade pointer clamped to the brake plate, will tell if it is bent.
You can probably get a more accurate reading if you take the brake drum off an check at the axle flange.
Exactly ^ ^ ^ However traditionally Ford's axle shafts and sector shafts are rather soft and can bend with a minor impact. I have paid for many in my days as an insurance adjuster. The one thing that bothers me is that you said the shop claims that there's a "bounce" in the wheel. A damaged axle shaft or damaged wheel won't bounce because you can't damage it to make it "bounce". As mentioned.... Pull the wheel & drum and get a dial indicator on it.
Waddayacare brought up something that I missed the first time around with the Bounce in the wheel. Take a floor jack and jack each wheel up a few inches off the ground and set something close to the tread of the tire like a jack stand or a block of wood and then spin the tire slowly by hand and see if it is out of round for some reason. That "bounce" in a tire might actually be a broken belt or tread separation. You can check the lateral runout on the rear tire the same way before pulling the tire and checking the axle for runout. He is correct in that some axles don't stand up to much of a side lick before getting bent either. I use to replace quite a number of them back when I was working in dealerships as I was the one who had to check all of the vibration issues.
Are you feeling the vibration in the seat which is normaly coming from the rear or in the steering wheel which is almost always in the frontend ?
Yes, definitely check for an out of round tire. Balancing will not cure the shake caused by an out of round tire. Think about it, you can balance a rectangle so that it spins smoothly, but the ride ****s.......
I don't think it's a tire or tread situation because I swapped left front with right rear to check for that, & I still notice the bounce (best way to describe it) on the left front.
Thanks for all the input guys! I'm going to do some testing as suggested & see if what I can find out. There's a shop here in town that specializes in differentials & axles. Gonna call them I see what they say too. Thanks again.
OK...it ain't a bent axle. I pulled the axle Saturday & took it to AZ differential & they checked it & said it was good. Next step...I'm going back to the front & see if I've got a bad drum that's out of balance.
Sounds like a bad brake drum to me, as posted earlier if you feel it in your **** its the rear, if its in the steering wheel its the front, simple check is to jack the rear ( put stands) start her up and put in gear you will see if theres a hop and you"ll feel the vibration if its in the rear, if not, your original gutt feeling is right its the front. tires are new and moved all around and no changes, brake drums are the only other thing that rotates
Check the U-joints while you're at it. Seen 'em do funny things at speed. Tire balance is good, tire run-out is good, no bent wheel or axle. A pesky u-joint can give a bad vibe, and not show up until a certain speed.
OK...looks like it's an out of balance brake drum. Took my ride to a place that will check balance with the wheel on the car. It definately was out of whack. After I gave them all the info on what I have done, they said it's gotta be the drum. Bummer is both front drums were replaced in 2009. Oh well, time to order up a new drum. Keep yer fingers crossed I get a good one. You had it right LCALIGNSHOP. Thanks again for all the input.
I ran into that once with an aftermarket drum on the rear of a pickup. Glad to see that you got things figured out even if it took some effort to do.
OK...way late on finally getting around to the replacing the front driver side drum with one I got from a buddy that did a swap to disc brakes on a 65 Galaxie. Guess what...that fixed it! It was a bad drum that was out of whack. Wish I woulda figured that out back when we replaced 'em shortly after I got the car. Coulda got it warranty'd. Oh well. I can cruise at 70 mph+ now!
Thanks for reporting back on it. They use the high dollar balancers these days to balance the wheel tire combination but it doesn't balance the total ***embly. The on vehicle balancers are difficult to find. What good does it do to balance the tire to 1/10 of an ounce when a drum can be 4 ounces out.
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