[Healeys] SAE 140 Use In Differential To Reduce Noise?

[Bob Spidell]

Interesting question.  My BJ8 diff also has a whine, though it occurs more off-throttle than on.

I have no experience with heavier gear oil--and it looks like no one else does, either--but I'll hazard a guess that the 
oil in the diff is slung about so fiercely that lubricating the axle bearings should not be a problem (except maybe when 
temps and machinery are cold--drive easy for a few miles, which is a good idea anyway).

If you do switch to 140 let us know how it works.

Bob


On 4/3/2014 7:42 PM, Graham Wilkie wrote:
> Hello All,
>
> The differential on my 1966 BJ8 starts to whine once I have driven for several
> miles, and everything has warmed up to normal operating temperature. It only
> occurs during accelerator pedal movement down (under load). The whining
> diminishes during coasting or deceleration.
>
> The differential is filled with Penrite 80W 90 mineral gear oil. (Recently
> changed).
>
> I am considering replacing my differential gear oil with Penrite SAE 140
> mineral gear oil. (Note no 'W' prefix; it is straight SAE 140). This product
> claims it will reduce differential noise in older vehicles. I wonder if it is
> suitable for our Healeys?
>
> I seem to recall reading on the List that our rear wheel bearings are splash
> lubricated by differential oil, but cannot find any reference to that in my
> workshop manual. Is that correct? I'm concerned that if that is the case, will
> the SAE 140 be too viscous to splash lubricate the rear wheel bearings
> effectively?
>
> Would I be better of using a gear oil additive like Nulon G70 instead?
>
> Any shared thoughts or suggestions would be greatly appreciated.
>
> Thank you.
>
> Regards, Graham Wilkie.
> BJ8 Moruya NSW Australia.
> _______________________________________________
>
>
>


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Bob Spidell           San Jose, CA            bspidell at comcast.net

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