[Vwdiesel] Mileage vs wear

[MWoodland at Dentsply.com]

Greetings.
I have a '91 Jetta 1.6 NA w the dreaded AWY box, and am considering
swapping out with an ACN, ACH, AGS or the like.
This would drop my rpms from 4k to 3k at 70 mph... not that I would ever
drive that fast.
A friend with an '85 TD mentioned that when his 5th gear fried, he drove
for a month using 4th on the highway, turning 4000 rpms, and his mileage
didn't change.
Should I take it that the only gain I will see is reduced engine wear and
noise from making the swap, and not fuel mileage?
best regards,
Mark

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