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Diff. Front plate fixing bolts, puzzle ?

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#1 David Baram

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Posted 01 August 2018 - 07:16 PM

Good evening. Not a problem, more a puzzle. 


With having the diff out to fit to replacement chassis, I thought I would fix the oil leak from the nose of the diff by changing the oil seal.

All went well. Made tool with long bar to hold the front flange; undid the nut with even longer pipe on the end of the nut tommy bar; flange withdrew easily with puller, then spend the rest of the day removing the old oil seal. What a job that was !!! Eventually came out. Awaiting replacement. Have chosen to use alternate rubber seal not leather. 


Onto the puzzle.   Removed the front mounting plate to get to the oil seal and noticed the securing bolts, Part 132856. Never seen these before. Puzzled as to the reason for the special shape of the shank. See attached and Rimmer site photo of 132856. A very special bolt indeed priced at £6.25 each. Note it is a 3/8" thread but uses a 7/16" shakeproof washer because of the shank shape. All bolts are OK so not having to purchase the bolts just the special internal shakeproof washers.


Why this profile I am asking ???? Mounting plate has a bore machined to suit the spigot on the casting of the diff so is located accurately I would think. Never seen this profile before. Any advice to set my mind at rest.  Just curious.


Thanks, David B



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#2 Paul J

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Posted 01 August 2018 - 10:03 PM

David I replaced my input seal but found the oil leakage was through the spline and nut, worth checking yours out. I used rhodorseal on my coupling nut and washer.
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#3 BlueTR3A-5EKT

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Posted 01 August 2018 - 10:20 PM


I too suggest it was done to centralise the mounting plate to the threaded hole to the bolt....

Peter W


PS I found the easy way to renew front pinion seal was to bash the edge of the shakeproof washer out to the reinforcing ring of the front plate

- the seal then passed through OK

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    Niall Callery

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Posted 02 August 2018 - 06:55 AM

David when putting those back in I suggest using some form of Thread Lock those came loose on a Diff I had and under excelleration caused the dreaded Clonk.
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#5 glasgow4a

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Posted 02 August 2018 - 09:53 AM

Rhodorseal? please explain, Ian.

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#6 stuart

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Posted 02 August 2018 - 10:55 AM

Rhodorseal? please explain, Ian.

Here you go Ian https://www.automoti...alnt-100g-tube/


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#7 David Baram

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Posted 02 August 2018 - 04:24 PM

Thanks all.

Paul J/Stuart,  I see the leak route you are suggesting. I have 'V-tech Vital Silicone Gasket Maker' on my shelf that has same properties as Rhodorseal.


TRNiall, Have purchased the appropriate 7/16 Internal Shakeproof washers, coming tomorrow, as didn't have any in my stock, but will also use thread lock.  Don't want the dreaded diff clonk after all this work.


Thanks, David B

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