Axle pinion nut too tight or to slack?

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gordini5
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Axle pinion nut too tight or to slack?

Post by gordini5 » Sat May 11, 2019 3:32 pm

A little help needed please.

I've changed the axle pinion shaft seal :) but when I slackened off the nut I noticed it seemed to be seated at very low torque.

Now when I try to line up the marks I made on the nut and pinion it is beginning to find its seat a 3/4 turn before the marks line up. My feeling is that if bring the marks back together it will be a good bit tighter than it was when I took it apart.

Is this what I should expect as I realise it is important not to over tighten it.



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Axle pinion nut too tight or to slack?

Post by Oldconn » Sat May 11, 2019 6:08 pm

The reason is probably that you have slipped the flange on a different spline from original. Pull it off again and wind it back a spline without turning the pinion. Pulling up the nut a fraction tighter is more desirable than leaving it slack.


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gordini5
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Axle pinion nut too tight or to slack?

Post by gordini5 » Sat May 11, 2019 9:28 pm

Thanks for the idea but doesn't seem to make it any easier. The marks I'm trying to line up are on the pinion shaft and nut but not the flange.

Would I be right in saying that it is easy to release the pressure on the preload but hard to re-load. So where I could undo the nut with an 8" long wrench I'm going to need an 18" long wrench to do it up again?

Sorry if this is obvious, lack of experience. :oops:



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Axle pinion nut too tight or to slack?

Post by AJL Electronics » Sat May 11, 2019 9:54 pm

Is your seal seated correctly? It should have taken some effort to release the nut and a reasonable torque to realign.


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Axle pinion nut too tight or to slack?

Post by Benc » Sat May 11, 2019 9:56 pm

I did this job last week on my 5 with axle on car on stands.

The steel ring of the seal was lower than the housing.

I marked the nut and shaft and needed a breaker bar to undo the nut which needed exactly 10 turns to remove.

When I refitted the nut I used my torque wrench for final tightening. I would say that 3 or 4 flats from aligning the marks the nut was tightening and needed a socket wrench to tighten.

I had to set my torque wrench to 140 ft/lb to align the marks just went past marks by a couple of mm only.

Axle was ok.

Best of luck with yours



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Axle pinion nut too tight or to slack?

Post by gordini5 » Sun Jun 09, 2019 1:10 pm

A belated thanks for all the help:) I've been messing about since, checking this and that as the new seal is leaking too. :(

I checked the seal was seated correctly, noted that there was very slight wear at the flange/seal but the seal seemed to make a good tight fit. As suggested it took exactly 10 turns to remove the nut but didn't go so far as 140 ft/lb before the marks aligned and a few mm beyond.

The old leather type seal was different and I think incorrect as it was clear the flange had cut a groove into the face of the seal housing.
old seal.jpg
leaky seal
old seal.jpg (244.76 KiB) Viewed 539 times
I assume a new flange would mean properly resetting the pre-load and so without suitable services locally I think I'm just going to live with the leak.

On the upside, I've re-bushed the aftermarket rear anti-roll bar. This must have been acting like a giant tuning fork as it has greatly reduced the axle whine heard when cruising at about 55mph. You win some, you loose some :D :D



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