someotherguy
Truly Awesome
1992-1995 it's in that little white plastic container behind the glovebox area. 1995 being a one-year-only setup, it's attached under the plastic tray the PCM sits on, so it's slightly more annoying to access.When MY speedo in the '88 K1500 went wonky, it had nothing to do with the VSS. The entire problem was the DRAC module in the instrument cluster going intermittent. In that the '88 had a 700-R4, I only lost the converter clutch, not various gears. Also lost cruise control and ABS, all of that relies on a signal from the DRAC.
I don't know where the DRAC is on a '95. Perhaps integrated into the computer.
While I do agree, I haven't seen many scenarios of DRAC failure on 1992-1995. I have however seen a few examples of odd transmission behavior like you describe experiencing, on the 1988-1991 trucks. The memory is extremely vague as the trucks weren't mine so I was hearing about it secondhand, and quite a while back. Speedo would go dead, and.......I want to say the TCC would unlock. The person I'm thinking of was in an '89 C3500 so that would have been a TH400. He'd smack the dash (I know; I know) and it would behave again for a while. This told me the problem was in the cluster, or possibly oxidation on the cluster connector pins.Mine had a VSS crammed into the transfer case.
Point is, "speedo dead and no upshifts" can be something OTHER than the VSS. Don't replace it "just because". Diagnose first, replace later. This could be a failed wire harness, failed DRAC, failed VSS...and probably some other issues as well.
Richard