Question about 1990 Chevrolet Suburban

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1990 Chevy Suburban 4x4 shifts late and hard, particularly at highway speeds. The husband thought it was acting as if it wasn't getting fluid through the filter (starving for fluid) and he changed the trany fluid and filter. However, it is still shifting late and hard, though, and we need to try to get it fixed before winter hits us for real (we live in Iowa). Any ideas what's going on with the transmission and how to fix? What could be

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There is a vacuum line that runs down to the transmission to the modulator. Either the vacuum line has came off on one end or the other. Or the modulator on the transmission is bad. It has to be one of the two.

Posted on Sep 28, 2010


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