I have used PS stop leak with good success in the past.. Looks like to me you have almost nothing to loose.. The stop leak only cost about $3.00.. PS fluid should not cost $10.00 a quart.. Autozone has Synthetic for abou $5.00 a quart..
Just remember.. It takes a little time for the seal to expand.. In the old days, we used to just pour some brake fluid in to swell the seals.. It's probably the same thing..
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