I will drive to work and the speedometer works fine. 3/4 of the way home in traffic or after accelerating it will drop to zero. Get home park it. An hour later go out and drive and its working again. This has been going on for about a month any idea whats going on?

I am pretty sure there is a recall on this. Take it in and get it fixed.

7 year 70,000 mile warrenty

#10 :)

I had this happen too about 6 months ago. The dealer replaced my instrument cluster at no cost to me. I was told that there was a TSB or a recall or something on it and that's why they replaced it at no cost. I just can't rember the details right now.


See this thread for more info.
http://www.dieselplace.com/forum/showthread.php?t=202006

The speedometer on my 04.5lly quit working a while ago, and I didnt want to pay to get it fixed. A month or so ago I got a letter from GM stating the instrument cluster problem with the speedometer and fuel gauge. The letter I got said if I had this problem take it to a local dealer and they will fix it for free. My truck was diagnosed with the problem but then they told me they couldnt fix it because it didnt fall within the 7 year 70,000 mile "parameters". I showed them the letter I received, that did not specify any parameters, and they still wont fix it. Then I spent 33 mins and 24 seconds on the phone with "customer service" explaining the situation and the highest supervisor told me that being a consumer herself she understands my situation, but legally there is nothing they can do because my truck is over the mileage parameters of 70,000 miles. She also told me that it is not considered a recall becasue nothing of harm could result of the bad cluster. She called it "special coverage". BUNCH OF CRAP!!!!!

That sucks. I was well over the 70K myself. I had bought the truck (used) from them almost 2 months prior "as is" with no warranty at all.

Maybe you should try another dealer.

04.5 LLY here, mine was acting up, no letter just took it in and got it fixed. Done Deal.

My wifes '05 Tahoe is going in on Monday to have the cluster updated. No questions asked. I would go with a new dealer.

MaxRock

mine was way over, 100k on the dually, i called gm, i bitched, and i got mine fixed for free.... try it

Mine was acting the same way for almost two months before all gauges went out completely. I had gotten the recall but have 135K so that was out. I bought a rebuilt one on e bay ($300) and put it in in the parking lot at work in 15 minutes.
The dash cowling pulls off with your fingers after dropping the steering wheel and pulling shift lever all the way down. There are 4 screws holding the cluster in and one wiring plug in the back. That's it. As I was wiggling the wiring plug, the gauges were turning on and off (as you will have to leave the key in to pull the shift lever down) and I'm not even sure that the connection hadn't become a little corroded and I may have not even needed to replace the cluster. What the dealer's want to charge for this job is outrageous.

Mines been a pita lately too. Dropping down to zero while cruising on the highway and as of yesterday, the new 0mph is actually 35 on the speedo, so I get to drive around town at 70-80mph on the speedo. I wonder if it's just the stepper motor how hard that'd be to replace.

I have an '05 GMC the TSB was issued for '03 and '04's. dealer told me there was nothing they could do for me. I then called GM customer service told them what the problem was and that I had 65,000 on the vehicle. told me to take it to dealer and performed check. cluster was bad. they are seeing some problems with '05 replaced cluster for $106.00.

I just got some new stepper motors yesterday and installed them this morning into my cluster. Took a bunch of pics and will try to post them up here this afternoon. Went pretty easy mostly, now to put it back together and see if it actually works!

I'm amazed at how GM blows people out of the water on these clusters. We have a saying around here with the GM steppers -- It's not a matter of IF the cluster goes bad, its WHEN. :cookoo:

Glad I saw this, I am taking my truck in as soon as I can. Mine has been acting up for about 3 months now and I thought it was just cause all the snow we got and plug the speed sensors or something...

GM would go broke if they HAD to fix or replace all the bad gauge clusters. They will only do the ones they have to do. It isn't only our trucks with this problem. I know that my Trailblazer and my Envoy also have these same problems.
It's not a bad fix to do just time consuming. Buy the stepper motors off eBay for around $10 ea. Also check your cluster lights if doing it yourself and replace them at the same time. They are also soldered in.

on my 98 6.0 the odometer went out and i just went to a "pick and pull" and in 10 minutes had it changed. unfortunately the mileage went from something like 128K to 37K, is the mileage still stored in the cluster in this way? I kept thinking that when I cycled the key or turned it on and off it would change to the trucks real mileage but it never did.

I have often thought that there has to be people out there with a switch or potentiometer or something to make each mile only count as a fraction of it by connecting them inline to wire xyz.

Charlie at Florida Speedometer is a supporting vendor. He sells one for under $200. I just installed one, and it works perfectly, and the lights seem brighter.