Lateral play in rear axle

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ManniB

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Jul 3, 2010
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Location
Affalterbach / Germany
My Car
1971 Mach 1
Hi,

today when I re-adjusted my Koni shocks on the rear end I noticed that I could lateraly move my RH rear wheel slightly in and out. Although I didn't measure it, I think the play is less that or equal to .02 inch. There is no movement on the LH side.

Is this play excessive?

Thanks, Manfred

 
Hi,

today when I re-adjusted my Koni shocks on the rear end I noticed that I could lateraly move my RH rear wheel slightly in and out. Although I didn't measure it, I think the play is less that or equal to .02 inch. There is no movement on the LH side.

Is this play excessive?

Thanks, Manfred
Manfred,

I've looked through every reference I have on the subject and did not find any specification for lateral movement. If there is no seal leak and no noise coming from the bearing, I'd drive it and check it periodically for increased movement. Axle bearings usually start making noise when they are going bad.

Chuck

 
My 5.0 with its stock 8.8 rear clunks like mad when I push on the quarter panels and rock the car. Definitely has more than .020" lateral movement.

My '93 T-bird (with 8.8 IRS) makes no noise whatsoever. It's solid as a rock.

Neither of which leak, grind or howl with normal driving.

Like Chuck said, sounds like no problemo to me.

 
That's good news. I forgot to mention that there is no noise and no leak at all. I will keep an eye on it.

Thanks, Manfred

 
I don't believe that it is unusual for axles that are retained with C-locks to have some lateral movement. I would be concerned with axles that are retained by the bearing retainer plates (such as 8" and 9" removable carrier axles) having any lateral movement. If the ball bearings or races were worn enough to have lateral movement they should also have up and down movement.

I've seen the entire axle and wheel come out when the bearing reaches a certain wear point. I'm not sure how much wear has to take place before this happens. I was following a pickup that was pulling a horse trailer with two horses at night when his right axle suddenly departed. It was quite a show with all of the sparks and the pickup and trailer swerving around, I don't know how he managed not to lose it. I helped the guy look for his axle and wheel, we tracked it by the gouge marks as the axle whipped around, it went several hundred feet out into the brush. The bearing had clearly failed and came apart.

 
My 5.0 with its stock 8.8 rear clunks like mad when I push on the quarter panels and rock the car. Definitely has more than .020" lateral movement.

My '93 T-bird (with 8.8 IRS) makes no noise whatsoever. It's solid as a rock.

Neither of which leak, grind or howl with normal driving.

Like Chuck said, sounds like no problemo to me.


You could rock my 85 GT with the original 7.5 rear end and it would sound like some one was underneath the car with a hammer. Later I went with a 98 Cobra 8.8 rear end when I switched to 5 lug wheels and Cobra brakes and it was much quieter. But with the axle C locks I knew it would never be noise free.

With the 9" in your Mustang Unless you hear a bearing noise or notice a seal leak you should be ok. They are pretty tough, ask the Chevy people who use them in their race cars.

I drag raced my Pewter Mach 1 mercilessly for years and the ONLY time I ever went into the rear end was when I got a great deal on some 31 spine axles and a 3:50 traction lok set up! Built Ford Tough! :)

 
If your 9" rear axle shaft has side play then I would suspect worn bearings as they are the only thing that side locates the axle shafts other than an incorrectly fitted retainer plate or improperly installed retaining ring behind the wheel bearing. It may seem quiet but I'd suspect some more noise vs new bearings. Small amounts of noise creeping in over the years is quite insidious and not easily singled out by the one who drives the car.

Side play on the axle shafts of a 7.5" or 8.8" are indicative of worn traction lock clutches. When freshly rebuilt, the C-clip spring, spider gear pin and c-clips are often a challenge to reinstall. But once fitted the axles are as tight as new.

 
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