It takes a fixed amount of engine power to drive at a given road speed.
I have raised the overall gearing of numerous VW van over the years and
it has never resulted in a very large improvement in MPG.

Without increasing the total power or changing the power band of the
power source you will be hard pressed to improve much on the factory
tranny gearing. Changing from a 4 to a 5 speed does allow a higher top
gear but only because it has a fairly close 4th gear to drop into as
needed and needed it will be.

Finally, the engine is cooled and lubricated by pumps turning in direct
proportion to engine rpms. Maintaining a high load on the engine while
lowering those rpms with a tranny gearing change should not be expected
to make the engine last longer.

Mark

Dart 330 wrote:
>
> >They are available for ballpark $2500 USD from Weddle Industries
>
> $2500 seems like a lot of money, $1495 sounds alot better. Can anyone
> who has one from weddle let me know if it is worth over half what I
> paid for my Vanagon? I would say at least 75% of my driving is done
> over 60 mph, I would like to improve my mpg and help the engine last
> longer, I guess if you consider engine longevity then a really
> expensive trans is worth it?? I would think lowering rpms by 1k on
> extended trips would help the engine last longer over several thousand
> miles of highway driving.
>
> Nathan
> 85 Westy
> 74 Bus