15-16 Trax tach face in Sonic cluster

[BigLee]

I've liked the Trax tach face over the Sonics, so I bought 2 used clusters, 1 Trax, 1 Sonic, from Ebay, $50 for the pair shipped.
I bought the spare Sonic cluster as the Guinea pig, and to cut and modify parts before I pulled my stock cluster to install the modded parts into.
It can be done, but it's not quite as straight forward as it might at first seem.
The Sonic's tach face is completely flat, but the Trax's tach face is dished, very similar to that of the ones in the Sonic RS, so I had to modify the inner tach bezel to clear the raised edge around the Trax tach face.

Here is a composite pic of both stock clusters:



And here is the final result:

 

[BigLee]

The housings are completely different, but all the lights are in the exact same places, and the main circuit boards are the same size and shape.

 

[BigLee]

There is a good bit of cutting/ trimming and test fitting, more cutting/trimming, ect. to make sure everything fits right.
I also brushed on a little low gloss black paint around the outer edge of the Trax tach ring, and in a few places around the Sonic's cluster, to help hide the trimming on the ring and to reduce unwanted light transfer to places I didnt want it around the cluster housing.
It's possible that this might fit into a Sonic RS cluster with a lot less work, but I'm not certain of that.
I have about 6-7 hours of work in this setup.

I had a bit of background light getting in around the inner bezel and outer edge of the tach face, so I decided to cut off the outer edge of the donor Sonic cluster tach face to prevent the excess light from getting through. It mostly worked, but I still have a tiny bit of light getting through in one tiny spot.
It was late, and I didnt have time to mess with it any more, so I calibrated the tach needle, snapped the cluster back together, and bolted it back in the car.
I'll deal with fixing this little issue soon. The cluster is easy to pull and with a few retaining clips snipped off, the cluster is easy to disassemble now as well.

 

[Mark r]

Does the whole cluster fit? I’d just swap it all out

 

[BigLee]

No. The Trax cluster has completely different mounting points, and the overall size of the cluster is considerably larger than the Sonic's.
Plus, the back cover on the Sonic cluster is what you see in the car, on the Trax, the back cover isnt visible, so it isnt smooth. Just square cut, hard edges, so I presume the dash covers it.
Not saying it cant be done, but would likely require some
extensive fabricating to make it look right.
The electrical connectors are the same though...

 

[Mark r]

I bought the traxs gauge for $20 just playing the waiting game now

 

[BigLee]

Awesome.
IMO, it really is better to buy another Sonic cluster as well, so you can modify the inner tach bezel without having to pull your stock one until the pieces are ready.
Plus if something goes wrong, gets damaged or broken, you're original cluster is still undamaged.

A few other things to note: The tach needle is a bit hard to pull off. Takes a fair amount of effort. A small 90 degree interior trim removal took helps.
Also, the tach lighting will be a bit brighter than the LCD display is, which is ok by me.
I'm not sure if the Sonic uses a slightly tinted overlay on the LCD compared to the Trax, as it has the clear lens that covers the entire display. I'll look at my Sonic donor cluster to find out.

When disassembling the Sonic cluster, go slowly and start at the bottom,then work your way around. Do any prying from the bottom so that any gouge marks are concealed from view. You can use a hook shaped pick tool to reach inside the cluster housing to unlatch the clips holding the upper side together.
Also, if you remove the clear plastic lens from the inner tach bezel before trimming on it,(recomended) just be aware that the retaining tabs on the bezel that hold the lens on are rather brittle and will break easily if you arent very gentle with them.

If you have any other questions, feel free to ask.

 

[Mark r]

I’ll get a sonic gauge too. Right now I’m just stock piling parts for summer. And thank you for offering the help.

 

[BigLee]

Daylight view.

 

[Mark r]

That looks so much cleaner. Did you change out the other leds and do one solid cooor? I was thinking about doing that as well

 

[BigLee]

Thanks.
No, all the LEDs are all permanently soldered to the board.
The tach background LEDs are white, the tach needle LEDs are red, and the warning light ones are whatever color you see.
All the waning indicators on the tach face and and around LCD display are all clear in the prints. The LEDs give them the color.
The blue and white areas in the tach dial are color coated in the face. See above pics.

I used all of my original cluster, except for the Trax tach face and needle, and the inner bezel around the tach that came from the donor Sonic cluster, which I had to cut the inner edge down to clear the raised Trax tach face.

 

[Mark r]

Let me get it here and look at it. I have another idea I’ll run it by you as soon as I get it