Speedo....97 gmc K3500

97 4x4 p-pump cummins swap, no computer in truck, dodge 4500/241, D80 rear, factory gauges, I have the factory gauges working except for the speedo. No computer or engine portion of the harness left in the truck. Looking for creative ideas anybody might have?? I've talked to Dakota Digital and they say they "think" they have what I need..... A converter box that will convert between the speedo signals used in vehicles but I'm not completely sure how it would work since I'm not running a computer anymore. I know Chevy uses 4000 ppm for the speedo, but not sure exactly witch signal or the signal for dodge? I know I know "search" And I have, but not finding the info I need, so if anybody has any suggestions then I'm all ears! this is not a major issue by any means, just be nice to have the speedo workin for mpg figuring and things. I have gps I use but we all know there's glitches and tweaks so the odometer part isn't that reliable lol. Thanks for any help.

I would think that any 4000PPM signal would work. The simplest way to do it may be to add in a GM rear case portion with a VSS in it and a 40 tooth tone wheel to the output shaft. Then run the 2 wires up to a GM VSSB and run your spoeedo that way. Does your current transfer case have a speedo drive setup in it? If it does you may want to contact HESCO(they do JEEP stuff) and buy one of there speedo drive setups that they use in the JEEP EFI setups. Then use that to trigger a GM VSSB to run the speedo. Modify teh VSSB with dip switches and fine tune your VSSB until it reads correct.

THEFERMANATOR said:

I would think that any 4000PPM signal would work. The simplest way to do it may be to add in a GM rear case portion with a VSS in it and a 40 tooth tone wheel to the output shaft. Then run the 2 wires up to a GM VSSB and run your spoeedo that way. Does your current transfer case have a speedo drive setup in it? If it does you may want to contact HESCO(they do JEEP stuff) and buy one of there speedo drive setups that they use in the JEEP EFI setups. Then use that to trigger a GM VSSB to run the speedo. Modify teh VSSB with dip switches and fine tune your VSSB until it reads correct.

Click to expand...

Hey man, you sound very knowledgable and strait forward, that's what I need. Anyway, I have access to a decent wrecking yard that my buddy owns, I think I have a tail housing lined up for the vss and can get a vssb, I get the idea of the vssb, but I'm not sure on the hook up as I've never fooled with one. I've been lookin in my book at the wire schematic on my truck and I see that the signal goes in the ECM as two wires, but goes to the cluster as one. I'm not sure bout how the 95-earlier is set up in relation to the later year. I understand how to do the dips, how to calibrate and all, and fairly knowledgable bout wiring but have not fooled with the speedo stuff enough yet to know a lot of what I need. I really appreciate any and all help you can give me. Thank you!