Factory tach in 91

[kwmech]

Looking at putting a tach in my Suburban, but do not want some gaudy looking thing hanging off the steering column. Looking at available parts at LMC using the factory style parts. Tach next to the speedo, and moving the fuel gauge to the lower left corner. Anybody tried this or have a list of pieces and parts.? The price for parts at the moment is about 350. with what I think will work

[68Timber]

Have you considered the tach from gmsportssalvage? I think that's the name. OEM appearance and the fuel gauge is in the 6 o'clock position like it was on the heavy duty trucks of the era.

[kwmech]

Similar thing I am looking at in the LMC catalog. Just wondering if anybody has done the same thing and what the results are/ were

[Ski-me]

If I were going to do it again, I might try the one Timber suggested. I pulled it up and they now have a stand alone tach with fuel gauge in lower left.

http://www.gmsports.com/tags/tachometer

When I did it, I didn't want some big thing hanging there either. I found a small one and then did major mods to the cluster to get it to fit properly.

[kwmech]

I'd like to put the fuel gauge in that spot just like the factory did and have the tach where the the current fuel gauge is.

[Irish1941]

I put a factory tach in my '89. It's tight but a tach can fit in the electronic speedo 90-91 gauge case. Im about to do it to my current '91.
Factory tach is a stand alone gauge. Pull the pins for the fuel gauge from the harness, rewire to small gauge and you're golden.

[kwmech]

That's the kind of answer I was looking for. I need to pull apart the dash for other repairs and I wanted to do everything at once including a new stereo. What about opening up the hole in the metal plate for the fuel gauge in the lower corner?

[Irish1941]

The metal plate is actually plastic. Exacto knife makes short work of it. Use gauge panel as a guide.
You'll need to drill a hole in the case, behind the fuel gauge to run leads from the main harness fuel gauge HOT. The fuel gauge is direct fit. Uses the clock mounts. Run HOT from the main cluster harness to fuel gauge and run a ground. Done.

We are just by passing the printed circuit to fuel and just running hard wired to new small gauge.

The tach harness passes thru the big fuel gauge you'll be replacing. No cutting or drilling there. GM never change the cluster case.
And tach mounts in same spot as fuel gauge did.
Lots of mis-info out there about how this isn't even possible with TBI, after '86, with 700r4, or with blah blah...works just fine.

Here's a better picture of it.

[kwmech]

Will I need the tach mount that is in the LMC catalog?

http://www.lmctruck.com/icatalog/csb/full.aspx?Page=93

bottom right corner 38-8069

my parts list........the tach itself 36-1882, possibly the mount 38-8069, fuel gauge 36-1858, wiring harness 36-1885. Should be it?

[Irish1941]

If I remember right, that bolts to backside of the tach.
I have only used OEM gauges but Im going to guess those will be same or pretty close
Think those LMC versions are plastic face vs metal factory.

[kwmech]

Bringing this back to life. Didn't want to rush into things. Anyways got it all apart this weekend and looks like some drilling in the back of the main shell is required for the tach to fit for the wiring harness. Also, where the smaller fuel gauge is to reside a lot of plastic needs to be removed and the battery lamp eliminated. Same shell used? or am I better off using the other shell, LMC only shows 2 shells---one with and without. Also, how does the electronic speedo unplug and does anybody know where I can have the speedo repaired? (travel odometer doesn't work)

[Irish1941]

Find 90-91 Suburban cluster case that had a clock in lower LH where new fuel gauge needs to go. Easy way to do it or just hole saw in your original case. The case has the area to be cut molded into it.
I can't remember how speedo comes out. Been awhile since I opened a 90-91 cluster up but if I recall it's straight forward. Should just come out after screws are out.

This is NOT one you want but you at least you can see the hole the clock uses.
https://www.ebay.com/itm/1981-87-Chevy-GMC-Truck-Suburban-81-1989-K5-Blazer-Jimmy-Gauge-Cluster-Housing/202582026775?hash=item2f2ad46a17:gM8AAOSwSrNaOplm:rk:29:pf:0

[kwmech]

Speedo is loose, what I'm trying to figure out is how the printed circuit unclips from the speedo head without damaging the circuit itself. Yeah I was wondering how to cleanly hog all that plastic out of the lower corner. I'm thinking of just buying a different shell from LMC. Need the tach mount I got, it bolts to the bottom of the tach and then mounts the tach inside the shell. Plus the screws on the outside mount the tach also. Just have to open up the backside of the shell for the harness to pass through.

[kwmech]

Couple of pics, every one likes pics

[kwmech]

Bottom pic I have to open up the hole in the center and remove to the line on the round dimple. (which will essentially create a hole there also) Then a small spot in the very lower area (which you can barely see unless you where to look for the tach mount)

Upper pic--the 2 slots (so to speak) all the way down and the bulb in there gets removed (it's a battery lamp)

That's why I was think of a different shell if this goes south I can put it back stock

[1968vetL-71]

Irish1941, what year was your tach out of? I have been wanting to put a factory tach in my 89 V3500, but also have heard not doable with tbi, etc... This looks like a fantastic resolution.

[Irish1941]

Originally Posted by 1968vetL-71

Irish1941, what year was your tach out of? I have been wanting to put a factory tach in my 89 V3500, but also have heard not doable with tbi, etc... This looks like a fantastic resolution.

It was 81-82 with the later font.
Very easy thing to do. I guess I should write this stuff down for future needs
TBI plays zero in to the tach
The 90-91 electronic speedo clusters are a tight squeeze as kw is finding out.
Try to find cluster case that had a clock. Easiest solution for fuel gauge wiring.

[1968vetL-71]

I ordered a new tach, harnesss, mounting bracket (if needed) and fuel guage. It will be here Tomorrow. I will try and get it all in this weekend and take step by step pics to document like you did. Thanks for the info.This will go in to my 89 V3500 Crew cab.

[Hart_Rod]

Updates and pictures?

[kwmech]

Just took these, still resolving the dash pad fiasco

[Hart_Rod]

Originally Posted by kwmech

Just took these, still resolving the dash pad fiasco

Can both tach and fuel gauge be purchased aftermarket?

[kwmech]

I got them both from LMC along with the tach wiring harness and tach mount. Had to change the power lead connector in the tach harness so it would plug into my fuse block. I also had to create my own small harness for the moving of the fuel gauge. Pulled the wires out of the dash harness and extended them to go directly to the gauge bypassing the printed circuit

[Irish1941]

Told ya it was simple
Looks great. Good job!

[kwmech]

Wasn't too bad. Cutting out the shell was a little tedious without damaging it as they are no longer available new. But yeah, I think it came out ok.