I was having that problem with my 85 and it turned out to be the
speedometer cable-- it was stripping out at the wheel point (it's a square
peg end that started wearing itself a round hole where it inserts, so it
wasn't really turning fully with each turn.) Had a used speedo cable with a
nice end glued/gooped into place (in the worn insertion point ) Works fine
now.

(and while the speedometer was out they hung it upside down for a half hour
with a few drops of oil and that took care of the "speedometer needle
Parkinson's" that was a separate, but annoying, problem...I had been just
living with taking an 'average speed' reading of the midpoint between where
the needle bounced. ie, if it was bouncing between 30 and 35 I figured
I was going about 32! <%-\   separate issue, but I didn't know that until
after it was fixed.)

--Patrice
85 "Vana Blue"

----------
> From: Paul Chubbuck <paul@OPTECS.COM>
> To:
> Subject: Odometer/speedometer inaccuracy
> Date: Wednesday, June 12, 2002 6:50 PM
>
> On a long drive recently, I checked and re-checked the odometer and
> speedometer in my 82 Vanagon.
>
> I found that to get an accurate mileage, I had to multiply the indicated
> mileage by 107%.
> To get accurate speed, I had to multiply the indicated speed by 110%.
>
> My tires are 195/70 R 15. I don't know if those are standard size or not.
> Can anyone explain these discrepancies?
>
> Thanks,
> Paul in New Mexico