two ways to beat it. one power washer/ two wax when clean then it will rinse off.

Not lacquer thinner, but plain old mineral spirits are great for removing sap, road tar, and general gunk from vehicles. Try a small patch first to see if it is effective. Follow it up with another wash with hot soapy water.

Your 1993 truck should have a base coat/clear coat paint job, but the clear coat on top will typically be fairly weathered by now, especially on the horizontal surfaces, creating a surface that is very receptive to the tars and sugars of tree sap and will hold onto them very well.

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Of the Troops & For the Troops

2003 chevy 4x4 bought new. 370,000 miles. Might have been washed half dozen times. No telling what may be behind seat.

Tom, when you get it clean, one of the prefab metal car shelters is money well spent and not a whole lot of money at that. Get one big enough for both the pickup and yer Suburban, and solve your problem for good.

Get a couple extra panels to cover the sides down about halfway and it will keep leaves and cedar needles off the vehicles, too.