Long uphill causes the oil temps to rise therefore causing oil
pressure to drop.  When you downshift you increase RPM increasing oil
pressure.

What oil viscosity are you using and what were the ambient temps?

On 3/30/09, Gregory S. Morrison <gsm@gregorysmorrison.com> wrote:
> Dear Vanagon Gurus: While driving on the interstate this weekend the oil
> light came on and buzzed when driving in 4th gear as we came to the top of a
> grade. It would go out and stop buzzing if I shifted down to 3rd.
>
> This has never happened before this weekend.
>
> I checked the oil level and it was normal.
>
> When the transmission was rebuilt several years ago we had a taller 4th gear
> installed for less engine strain and better gas mileage at freeway speeds.
>
> Thanks,
> Greg
> 86 Syncro Westy
>

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Chris S.
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