Originally Posted by 48ton1/2wrckr
The one I have has a vacuum leak and it looks like the rubber diaphragm has dry rotted. Just wondering if anyone ran into this and had any suggestions.
on my gmc i tried to replace the diaphragm by using a piece of innertube. problem is the tube is too thick and i couldnt get it to work. i ventured into getting the proper material and over time i decided to just leave it alone. on the chevy they used or at least on mine they used a linkage rod that went from the shifter to the adaptor. i messed with that one too and left it alone. since i know my speeds and what the the speedo reads i just make a mental adjustment in my head. it was too much effort for so little to gain. the only time i am concerned with the speed is in hi gear hi range. which both are about 50 mph.