I want to add a tach - need opinions, factory or aftermarket?

I plan to add a tach to my truck. It's got the typical blank spot over the steering column. I like the idea of a factory tach from a used instrument cluster but I've heard that many of them are not too accurate or may not work at all. I'd hate to buy a cluster and find out it has a non-working tach. Hopefully I'd be able to return it but even if it works, how do I know it's accurate? The alternative would be an aftermarket, probably mounted on the steering column. Any opinions on which way to go?

I like the factory tach in my truck. Accuracy? I don’t know, never checked. I think it’s close.

If I was going aftermarket, I always liked the Sun tachs, which are no longer made. So I’ve had good results from Equus on gauges so I’d probably go with this one. I guess I’m old school, just like the way they look.

https://www.iequus.com/6078.html

I agree with Dane - I like the factory tachs.  When I got Big Blue it had a huge tach that obscured part of the speedo strapped to the steering column.  I removed it and added a factory tach.  Not too worried how accurate it is, but it works well.

Steve - You are lucky that Ford discontinued the idiot lights for '86, so we know you have gauges.  And that is important as you can only add a tach to the gauge cluster, and on the trucks with gauges have the right wiring.

 

Well, I guess I'll pull the trigger on a gauge cluster. I've been reading up on it so I know I should already have the wiring for it, and the new cluster will have the ribbon cable so I think that is all I will need. Thanks!

I was lucky a member found a used one with the printed board for me.
It worked and still dose when installed.

Accuracy? I also don’t know as I never checked it.
I like that it moves as it should and it fills that blank area.
I dont really use it for anything like shifting.

I would say go for stock as the after market ones tend to block the other gauges in most cars / trucks.
Dave ----

I have actually checked the factory tach against my digital timing light, and the RPM's were bang on the money at least up to 2500 RPM or so (as far as we checked). I was doing some timing checks and we checked it in increments from idle all the way to 2500 or 2750, I forget now.

Good to know. Hopefully they are mostly accurate since I just bought a cluster.

I'm late, but 2 weeks ago, I bought a 3" Equus and mounted to the column.  With zip ties currently.  I come from a long line of column mounted tach people, so this works and throws back to the days.  My son now thinks it is a proper hot rod.

 It's wired in neatly.  Just looks like roadkill with the zip ties.   Seems to work correctly.   3" covers the blank spot nicley without overlapping the speedo or being too small.   I don't remember the rotate process on photos, so just turn your head sideways, please.  

That's a good option. It looks good and it doesn't block the other gauges.

A problem with a column mounted tach is that you won't be able to see the shift selector for your AOD.
I'm using a factory tach with my C6. I also checked it against the readout on my timing light and it seems pretty accurate.
I had heard that the factory tachs like to sometimes stick in the cold. I opened mine up and cleaned all the old yellowing goo from the circuit board with some rubbing alcohol before installing it and I've never had any issues with it sticking even at deep-freeze temperatures.

I forgot about the shift selector. It would definitely block that. Anyway, I'm going with the factory tach. Already shipped.

I checked my standard 6K factory tach as well as a couple medium duty 4K and 4.5K tachs (on my straight six with the 8 lug insulated). I compared them to a tach/dwell meter, and they were all really close.

The older, non-integrated circuit units seem to have more issues with sticking in cold weather or infrequent use, the later (late ‘85/86) with integrated circuits have fewer issues. That said I’m running an old, non-integrated circuit 4,500 rpm unit in my 81 and it has been smooth and accurate for about 4 years now.

Then I'm lucky that the one I ordered is an '86.