Hi Jim.  Because synthetic oil penetrates better, and cleans better, new
leaks can happen when you go synthetic.  You can change back, since
synthetics are completely compatible with dino oil, but the leak will likely
continue.  Dino oil doesn't make seals swell any more than synthetic does.
At 137,000 miles, a little leak is to be expected.  I'd stay with the
synthetic, the better lubrication is worth it, and I use only synthetic.  And
regarding synthetic blends, you get what you pay for.  Dino oil with some
synthetic is better than straight dino oil, but not as good as straight
synthetic.
Zoe Ann & Roger
1987 4x5 Adventurewagen (synthetic oil, leak free wasserboxer, soon to be 5
cylinder)    :)

In a message dated 5/24/99 10:24:14 PM Pacific Daylight Time,
shortlid@JUNO.COM writes:
> It is already to late!  You can't switch back once you have gone over to
>  Syn. lubricants!  Sorry, That is why i use Syn. blends, Best of Both
>  Worlds!!!!  Pure Syn. always had a problem with leaking it doesn't swell
>  gaskets like dino. juice does.
>
>  On Mon, 24 May 1999 21:46:49 -0600 Jim & Melody <JiMelody@ZIANET.COM>
>  writes:
>  >Hi all,
>  >Based on advise from the list, I had Redline synthetic MTL put in my
>  >91
>  >syncro in April.  My mechanic initially questioned my decision saying
>  >that
>  >one problem with a synthetic oil change late in life (137,000 miles)
>  >is that
>  >the synthetic tends to find any little hole to leak out of.  We'll, I
>  >think
>  >he's right.  Maybe it is not related but I've started loosing possibly
>  >a
>  >teaspoon or less of synthetic oil on my driveway overnight.  My
>  >question to
>  >you all is, would changing back to regular GL-4 make a difference once
>  >a
>  >little leak starts?  I can't say for certainty where this oil is
>  >coming from
>  >but it appears to be from between the tranny and engine.  Thanks in
>  >advance
>  >for you comments.
>  >
>  >Jim
>  >91 Syncro AW
>  >Alamogordo NM
>