Factory GM Guages ADD tach?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Best truck design

Full Access Member
Joined
Oct 7, 2018
Posts
83
Reaction score
36
Location
Lexington KY
First Name
Chas
Truck Year
1973
Truck Model
Sierra C2500
Engine Size
350
Has anybody here done the Factory Tachometer ADD to the GM cluster offered through LMC?

You replace the huge fuel gauge with a factory looking tach and place the fuel gauge over in the small gauge clusters.( in my case replace the huge BRAKE light with a fuel gauge.

In order to do this change you need a tach, wiring for the tach and the Mylar wiring schematic for the back of the gauge cluster?

Thought comments?

You must be registered for see images attach
 

RetroC10Sport

Supporting Member
Supporting Member
Joined
Sep 29, 2010
Posts
17,194
Reaction score
2,526
Location
Green Bastard Parts Unknown
First Name
Jay
Truck Year
2001
Truck Model
pontiac aztek
Engine Size
3.4
It can be done, but it's a pain.

I do plan on adding a factory tach and fuel gauge to my daughter's '73 Cheyenne when we get a chance. I have one that works, just need to get the wiring for it. I will be adding it to the cluster but just running the fuel gauge wires to a custom connector separate from the mail cluster.
 

Camatruder

Full Access Member
Joined
May 11, 2016
Posts
294
Reaction score
1,073
Location
Belgium
First Name
Rik
Truck Year
1991
Truck Model
K5 Blazer
Engine Size
350ci / 5.7l
I did the conversion a couple of years ago on my '91. It's not exactly the same as a '73 but very simular. All wiring was included or ordered separately, can't remember. What i can remember is that it was not very hard to do. I did find some pics.
You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach
 

Camatruder

Full Access Member
Joined
May 11, 2016
Posts
294
Reaction score
1,073
Location
Belgium
First Name
Rik
Truck Year
1991
Truck Model
K5 Blazer
Engine Size
350ci / 5.7l
I did had to install an emc filter afterwards, the needle of the tach was too shaky. Found that on ebay.
You must be registered for see images attach
 

Best truck design

Full Access Member
Joined
Oct 7, 2018
Posts
83
Reaction score
36
Location
Lexington KY
First Name
Chas
Truck Year
1973
Truck Model
Sierra C2500
Engine Size
350
Thanks I love the look of the factory gauges and think GM was at their peak for truck design back in the 70's. IMO this is the best looking truck that was made (dash included).

I will be doing the conversion at some point.
 

Best truck design

Full Access Member
Joined
Oct 7, 2018
Posts
83
Reaction score
36
Location
Lexington KY
First Name
Chas
Truck Year
1973
Truck Model
Sierra C2500
Engine Size
350
I did the conversion a couple of years ago on my '91. It's not exactly the same as a '73 but very simular. All wiring was included or ordered separately, can't remember. What i can remember is that it was not very hard to do. I did find some pics.

Did you get your gauges from LMC?
 

Camatruder

Full Access Member
Joined
May 11, 2016
Posts
294
Reaction score
1,073
Location
Belgium
First Name
Rik
Truck Year
1991
Truck Model
K5 Blazer
Engine Size
350ci / 5.7l
yes i did.
 

usar17

Full Access Member
Joined
May 3, 2012
Posts
596
Reaction score
17
Location
PA
First Name
Shawn
Truck Year
1985/87
Truck Model
K20 Silverado
Engine Size
TBI350/700r4/NP208
I did the conversion a couple of years ago on my '91. It's not exactly the same as a '73 but very simular. All wiring was included or ordered separately, can't remember. What i can remember is that it was not very hard to do. I did find some pics.
You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach
Exactly what I need to do! Couple questions.

Did you have to cut the hole for the tach connectors?

What kind of connections were on the fuel gauge?

Did you have to modify the bottom left hole any for the fuel gauge to fit since that's normal a blank with just battery indicator?

Did you do anything with the battery light?

Sent from my SM-G950U using Tapatalk
 

Honky Kong jr

Super Sarcastic Man
Joined
Jun 14, 2016
Posts
14,968
Reaction score
9,833
Location
Denver,PA
First Name
J-me
Truck Year
87
Truck Model
V10
Engine Size
Lil BB 407
Exactly what I need to do! Couple questions.

Did you have to cut the hole for the tach connectors?

What kind of connections were on the fuel gauge?

Did you have to modify the bottom left hole any for the fuel gauge to fit since that's normal a blank with just battery indicator?

Did you do anything with the battery light?

Sent from my SM-G950U using Tapatalk
5k rpm meh not enough lol
 

Camatruder

Full Access Member
Joined
May 11, 2016
Posts
294
Reaction score
1,073
Location
Belgium
First Name
Rik
Truck Year
1991
Truck Model
K5 Blazer
Engine Size
350ci / 5.7l
Exactly what I need to do! Couple questions.

Did you have to cut the hole for the tach connectors?
Yes, see pic 2 in post #3.

What kind of connections were on the fuel gauge?
I can't remember having problems with the fuel gage. I proably just connected the 2 wires from the old big gage to he new small gage.

Did you have to modify the bottom left hole any for the fuel gauge to fit since that's normal a blank with just battery indicator?
yes, a little, see same pic.

Did you do anything with the battery light?
Well here i went wrong at first. I first connected the light to the instrument cluster lighting to use it for my new litlle fuel gauge, but every time i put on my lights the alternator stopped charging the battery, you know battery light on, no charging. So i simply disconnected it. New litlle fuel gauge is in a kind of dark place at night but it's not that i have to look at it much. If the battery was not charging i would see that on my voltage gauge.

Sent from my SM-G950U using Tapatalk
 

Latest posts

Forum statistics

Threads
44,435
Posts
957,869
Members
36,802
Latest member
mcflurry
Top