Hello. I would like to ask for some advice please. From time to time when im going down the road mainly on the interstate when im doing about 70 or so my speedometer will stick. When i stop and and get back up to speed 70mph is my 0mph so when im doing 50 my speedometer is reading 120mph. I have noticed if and when it does that i can turn the the truck off and start it back up it will reset back 10mph so i have to do that like 7 or 8 times to get it back to 0mph were it should be when i take off. Does this make sense? Any help would be greatly apperciated.
Thanks, Michael

 

I forgot to add what kind of truck it is sorry. It's a 2003 Silverado Z71 regular cab with a 5.3 if that helps anyone that may have advice. So thanks in advance to anyone who may have some.

 

sounds like a VSS (vehicle speed sensor)

 

This is a common problem for the speedos. This was a poor design. I took the little motor apart that runs the speedo, and sprayed it with some contact cleaner. It works good as new.

 

Replace stepper motors in cluster :
They are 6 total, 1 for each guage
I would replace all of them.

Materials:
1. One or more stepper motors. The updated stepper motor part # is X25 168
bad OEM # X C5 168
2. Fine rosin core solder

Tools:
1. Desoldering tool. There are several types. Some are “suckers” that you use with a soldering iron to pull the solder out of the joint. The one I used is from Radio Shack for about $11. It is a 45 watt soldering iron with a hole in the tip and a rubber sucker bulb.
2. Soldering iron. About 25 watts is good for this job.
3. 7 mm nut driver or equivalent.
4. A small flat blade screwdriver.
5. A kitchen fork. (yes, details later).

Procedure:
1. Set the parking brake. If it doesn’t work, block a wheel.
2. Turn the key on and pull the shift down to “1”. Chime goes “ding ding …”
3. Pull the tilt wheel all the way down.
4. Pull off the dash bezel. It uses spring retainers so pull it straight back.
5. Take out the 4 screws (7 mm head) that hold the cluster in.
6. Work the cluster back. Release the electrical connector at the top back of the cluster by releasing the retainer. Unplug the connector.
7. Remove the cluster. It’s a bit of a squeeze between the top of the dash and the shroud thing on the steering, but it will come out without breaking anything. Honest.
8. Take the cluster to your clean, well lit work space. Plug in the desoldering tool and soldering iron to heat up.
9. Take the back off the (black) cluster by using your small screw driver releasing the lock tabs that hold it to the (white) frame part. You are now looking at the back of the cluster PC board.
10. Take off the front lens/bezel assembly. It has lock tabs at the top and bottom to hold it to the white part. The top ones are easy with a small screw driver. The bottom ones are a bit of a bitch. Mild cursing helps.
11. The PC board is now being held in by the gauge needles. You have to remove all the needles even if you are only working one stepper motor. The guy who sold me the stepper motor provided directions to get the needles back on pointed to the right reading but I got it wrong. More later.
12. Twist each needle a little counter clockwise to break the bond between the needle and the stepper motor. Use the kitchen fork to lift off the needle. No need for a 10 ton porta-power.
13. The circuit board will now come out. Be REALLY SURE you pull the stepper motor you want to replace. Maybe mark it with a Sharpie.
14. There are 4 pins that come out of the back of the stepper motor and are soldered into the PC board. Take your now hot desoldering tool, squeeze the bulb while NOT pointed at the PC board. (We want suck, not blow.) Melt the solder and suck it up. Repeat for each of the 4 pins.
15. The motor should now be easy to pull off.
16. Put the new motor in its place. There are locator pins. Make sure it is flush against the PC board.
17. Take your soldering iron. Make sure the tip is clean and tinned. Solder each pin to the PC board. Heat the board pad and the wire; then let those parts melt the solder. Don’t try to melt the solder on the iron then try to dab it in. That doesn’t work.
18. Examine your solder joints carefully. They should be smooth and shiny, flowed onto the pad and the wire.
19. Unplug your soldering iron and desoldering tool. If you are lucky they will cool off before you accidentally grab the wrong end of one.
20. Place the PC board back in the middle (white plastic) frame. Put the back cover on, press the retainers down until they lock.
21. Replace the instrument needles. The guy that sold me the stepper motor recommended pushing the needle on pointing at mid scale, then twisting to the bottom of the scale. Try it, but this didn’t work out for me; maybe I didn’t understand correctly. Hence:
22. DO NOT PUT THE FRONT LENS PART ON YET. More later.
23. Put the cluster (less the front lens) back in the truck, with the cable plugged in. Don’t put in the screws yet.
24. Start the truck. Oh, shyte, no start. Oh, I’m in first gear. Neutral safety switch. Put it in park and really start it this time. Watch the gauges come to life. In my case some were reading really whack.
25. Shut off the truck. For each gauge that is not reading bottom of scale, pull the needle off and put it back in pointing at bottom of scale. Repeat this step a few times until you have it all right.
26. NOW put the front lens back on your cluster. You can do this with the back part of the cluster in the dash. Push until the locks click.
27. Put back the 4 retaining screws and the dash bezel.
28. Take the $500 you just saved and buy something you really wanted.

 

Admin , Maybe a decent sticky here , A ?

 

Their are a few thing you have to know about trucks. Generally once you go over a 3inch, say a 4-6 inch lift you loose power, gas milage and increase rpm. then if you put over stock size tires you will screw up your speedometer. it will run slow cuz the gears are working differently then enginared for stock. Your Speedometer runs of your Wheel Speed Sensors. and your odometer runs of your speedometer so that will be banged up too.

 

That is also most important thing.

 

Does anyone have a chevy parts number for the speed sensor?

 

hay man in my experiance I have seen a few problems the clusters in those trucks go bad so my suggestion is to see if u can get your hands on one to use as a test piece maybe a buddy who has the same truck or something like that.Also there are companiesip sh out there that repair them if you ship it to them. Oh yeah by the way if u do end up going that route the truck will still run with out the cluster .hope this helps a little