Can I put an SS speeedometer in my LS?
 

Hey guys, I was wondering if i could install the SS speedometer ,with the volt rating and oil pressure, into my 04 Monte Carlo LS which currently has only the speedometer with the fuel gauge, speed, and RPM. Would I need to hook up some new sensors for the gauges for the cluster or is it a direct fit plug and play? I was thinking about buying the SS cluster, sending it to a repairer/ Led repairer to have all new stepper motors and new LED lights put into it but i dont want to spend money on it without being sure, thanks.

You can definitely do it, however, the speedo holds the mileage, so you'll have to document and properly move that over, or have documentation done for it so it doesn't look like fraud.

Also, I believe the oil pressure doesn't work on the LS

I'll confirm, it is a plug and play swap. The odometer reading is in the cluster as well as the BCM. I'm not aware of a way to update the speedo, so as Chibi said, document everything or swap with a cluster that is close to the same mileage.

Everything is plug and play, no sensor swaps. Down side, no one has found a way to get the oil pressure gauge working.
I am aware of:
- The SS cars have a oil pressure sending unit and the LS has a oil pressure switch
- Both SS and LS have a line from the oil unit going to I believe pin 19 on the PCM (not sure if the pin is accurate, that is from memory, but I know 100% it's the same pin on the PCM regardless).
- The LS does not use a ground wire (I suspect it grounds to the block).
- The SS has a ground wire, but I wonder if it's not truly a ground, if that is the case, it may require being hooked to the same exact ground circuit as the SS, which goes to a certain pin on the PCM.
- The PCM in a LS and SS are the same pieces of hardware, different software. I suspect to make the oil pressure gauge work may be buried in the PCM programming (as the BCM software I speculate is the same between a SS and LS).

Even though I do not have a LS Monte or an Impala to do that swap to, I would love to read of someone making the oil gauge work.
I hope the info I gave helps if you choose to dive into it further.

I have an LS with the SS cluster and will confirm that the mileage will be off and the oil gauge will not work. I would say you really don't need the oil gauge and it doesn't bother me not having one. Also on top of what Jason said about the PCM's i wonder if you got a PCM from an SS and got it tuned and maybe ask the tuner if they could make the oil gauge work somehow might be a possibility. What's your thoughts on this, Jason?

I have looked in both the DHP PowrTuner Software and HPTuner software, there are no settings for the oil pressure anything. I did the same with the TinyTuner companion software and talked to the owner of that software. Unfortunately, it would require a lot of reverse engineering skills I do not have.

My idea about the PCM, it does not matter if the PCM is a LS, SS from a Monte, Grand Am, whatever. As long as the Service Number is correct and it is re-programmed with the SS software, re-tuned for a LS. The "theory" on this is that the SS software has a setting or additional programming to make use of an oil pressure sending unit (instead of a switch). Since none of the tools on the market that I know of have options for this obscure setting, this is a LONG work around to that problem. If someone wanted to play with this idea, I have a TON of software files for stock PCMs I would be happy to share.

Here's another interesting note. The Impala's use the same clusters as our Montes (plus a couple additional options). I've heard that there is an Impala with a 3800 but base style gauges, swap the SS cluster in and swap the oil sensor and the pressure gauge simply works. Again, I don't know if the Impala info is true.

Dang that sounds like a long process. And that Impala doesn't sound bad, i'll have to ask around on the Impala forum

Great question Blactout. I was considering the same thing. Wish I had a positive answer for us.