Tachometer replacement thoughts

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SirRobyn0

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So back when I bought this truck 4 or 5 years ago it didn't have a tach in it. After the first time I towed my trailer with a load on I decided I needed a tach, so I bought a cheapie Equus unit, knowing that it was kind of stop gap, not the best quality but would perform the function. Well now it's starting to fail, occasionally it'll stop reading for a short time. I've checked the connections and believe that the tach is starting to fail.

Option #1, replacing it with another aftermarket tach, which is fine with me, but it needs to be a traditionally or classic styled instrument that fits in with the rest of the truck and does not standout as looking to modern.

Option #2 The other option would be to get a factory tach kit from LMC. I'd be curious to hear from other folks that have done the LMC kit. I actually kind of wanted to do this back when I got the aftermarket unit, and while I'm in there I could fix a couple other issues with the instrumentation. Biggest con with this is cost

What you guys think? Thanks.
 

Redfish

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I am very interested in this as I have been considering this myself. I would love to have a factory looking setup, just buy the small fuel gauge and move it down to the left. Of course I would have to remove the QUARTZ!!! clock...I have no idea why they made such a big deal about that Quartz Clock but they made it sound like a great thing.

Do you have to replace the entire printed circuit board?
What wire/where does the tach get its input?
 

PeteJr

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Last summer I replaced the big gas gauge with a tach and moved the gas gauge to where the clock was.
I tried to order the "kit" to do this from LMC. It was backordered for 6 - 8 months. I finally got tired of waiting and ordered all the individual pieces which "amazingly" they had. Paid about $100 more than the "kit" price. I ended up having to get the back panel also as the new, small gas gauge didn't mount in the place where the clock was on the old one.
You will need the correct printed circuit for sure.

I have pics and can list the items I bought if anyone needs it. I have an '83 GMC Sierra Classic SB.
 

SirRobyn0

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I am very interested in this as I have been considering this myself. I would love to have a factory looking setup, just buy the small fuel gauge and move it down to the left. Of course I would have to remove the QUARTZ!!! clock...I have no idea why they made such a big deal about that Quartz Clock but they made it sound like a great thing.

Do you have to replace the entire printed circuit board?
What wire/where does the tach get its input?
LMC sells a kit and their kit includes a new circuit board so I would think that's a requirement.

As for the clock is you think about the time period when these trucks came out, no other truck had a built in clock. What a luxury! My clock is dead and the aftermarket radio has a clock as does my GPS so I won't miss that at all. I have wondered though if I would miss having the large fuel gauge.

My oil pressure gauge isn't the best any more so I'd change that while I'm in there and I think replacing the circuit board could only do me good. But the kit is like $315 that's money I could put towards a bed cover if I go with a less expensive aftermarket tach.
 

SirRobyn0

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Last summer I replaced the big gas gauge with a tach and moved the gas gauge to where the clock was.
I tried to order the "kit" to do this from LMC. It was backordered for 6 - 8 months. I finally got tired of waiting and ordered all the individual pieces which "amazingly" they had. Paid about $100 more than the "kit" price. I ended up having to get the back panel also as the new, small gas gauge didn't mount in the place where the clock was on the old one.
You will need the correct printed circuit for sure.

I have pics and can list the items I bought if anyone needs it. I have an '83 GMC Sierra Classic SB.
The pics for sure would be great to see for me at least. I always seem to get into a time crunch on projects like that so seeing it would be helpful for me. Thanks.
 

Catbox

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This is the tach in my truck.
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I have too much torso, so I can never see it through the steering wheel when I drive it.
Soon I will be replacing it with a used Autogage unit that I picked from a swap meet.
These 3-3/4 inch tachs have always done well for me.
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I have a few of them to choose from as I always snap them up from the swaps when I spot them for $5-$10 each.
 

PeteJr

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Here's the list of parts I ordered from LMC.
My truck is an '83 GMC Sierra Classic. Parts differ for other years.
This process isn't too hard to do. I removed the dash pad, helps a lot.
Make sure the speedo and tach wires go in correctly so you don't have to remove the cluster after installing it. (Lesson learned)
I used some Testors model car paint for the older gauge needles.
I also, used a small rubber plug for the hole in the lens when the clock stem was. Just to keep dust out.........

36-2042 Tach - 7,000 RPM
36-3104 Tach wiring harness
38-8069 Tach bracket (didn't need it)
36-1858 Small fuel gauge
38-8101 Gauge cluster backing plate
38-8041 Printed circuit
38-1103 Dash bezel - brushed aluminum (handle with care or it will crease very easily)
36-0190 Instrument bulb holders - as needed
38-8042 Retainer clips for printed circuit - as needed
As for the clear lens over the gauges, I polished mine and it looks fine
There's other items you may need like spacers, clips, screws and headlight lens, etc.

Hope this helps !

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Soundmound

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I've been eyeballing the LMC kit but it's been out for months. I had them send me the parts list and I built it in my cart where I realized it would be almost $200 more doing it this way. I went as far as to buy a set of used gauges to try and rebuild what I had. However, what I got was for a different year than I needed as when it arrived it had a mechanical oil pressure gauge. I'm at the point now where I just want gauges back and will probably skip the tach conversion to do a like kind replacement, but will definitely NOT be reconnecting the clock as it is a parasitic drain that I don't want to deal with
 

SirRobyn0

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want to keep your clock? here ya go! :)
Tell me about that installation. I've seen those gauges I think out of medium duty trucks? I'd like that actually even more than the LMC kit, but my clock would go and my trans temp gauge would go in it's place. So how much work is that installation?
 

SirRobyn0

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Here's the list of parts I ordered from LMC.
My truck is an '83 GMC Sierra Classic. Parts differ for other years.
This process isn't too hard to do. I removed the dash pad, helps a lot.
Make sure the speedo and tach wires go in correctly so you don't have to remove the cluster after installing it. (Lesson learned)
I used some Testors model car paint for the older gauge needles.
I also, used a small rubber plug for the hole in the lens when the clock stem was. Just to keep dust out.........

36-2042 Tach - 7,000 RPM
36-3104 Tach wiring harness
38-8069 Tach bracket (didn't need it)
36-1858 Small fuel gauge
38-8101 Gauge cluster backing plate
38-8041 Printed circuit
38-1103 Dash bezel - brushed aluminum (handle with care or it will crease very easily)
36-0190 Instrument bulb holders - as needed
38-8042 Retainer clips for printed circuit - as needed
As for the clear lens over the gauges, I polished mine and it looks fine
There's other items you may need like spacers, clips, screws and headlight lens, etc.

Hope this helps !

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That's awesome. Any chance you'd be able to give a rough time estimate on the job?
 

SirRobyn0

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I used an Autometer #2891 (2 5/8"). I screwed it to the shifter column. When I'm in drive it's straight up.
I like the gauge but not the installation. I can see the appeal to do it like that, but my current tach is attached to the dash pad screw by the ash tray and that location is fine for me.
This is the tach in my truck.



I have too much torso, so I can never see it through the steering wheel when I drive it.
Soon I will be replacing it with a used Autogage unit that I picked from a swap meet.
These 3-3/4 inch tachs have always done well for me.

I have a few of them to choose from as I always snap them up from the swaps when I spot them for $5-$10 each.
I like the autogage and will keep that one in mind thanks.
 

Kurnacopia

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I did a complete bezel swap on my 74 K5. I found a guy that had a 73 suburban with a newer model cluster in it. BUT, the problem I am finding with getting things used is the plastic is so very brittle and can break off in a heartbeat when putting things together. Many companies sell the Cluster Backing Plate but never the one you need and LMC does too, but not all of them. So I highly recommend the LMC kit because all of the plastics are brand new, as well as the print out. Things will go in and seat perfectly and be solid for years to come. Thats my 2 cents.
 

StickyLifter

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I've been eyeing the LMC kit, but I may got with a Dakota Digital unit instead. Probably won't do either until next spring.
 

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