88 Gauge cluster calibration code

[70chevyfreak]

I am looking for a low milage gauge cluster for my 88 K-1500 and heard that if the calibration code on them are different they wont work right. Is that true. Also my old cluster is missing the shift selector cable. Where does it hook to the column and are they avaliable.

[ChevLoRay]

There are posts on here that have mentioned a DRAC module and it seems that is the key to swapability. Of course, I can be wrong. I'll see if I can find that post.

The following information came from ChevyTech in a reply that he did on another post about swapping clusters. These may be of some help to you.

Here is a very good article of how to do the swap:
http://www.fullsizechevy.com/forums/...es-w-tach.html
Here is an article that gets into DRAC calibration at the message board. The more you get to know about this, the more questions you are going to have.
http://67-72chevytrucks.com/vboard/s...=1#post2952083

[ChevyTech]

I the vehicle did not have the same rear axle & tire size from the factory the speedo would need to be recalibrated to read correctly in your vehicle.

A 1988 truck does not use a separate DRAC (Digital Ratio Adapter Controller). The digital Ratio adaptor is built into the speedometer.

Back in 1988 we would remove the speedometer cluster, connect the calibration harness, and momentarily touch the harness to battery power, which burns part of the circuit. The calibration harness kit, GM part number 25085515, comes with two "Programming clips". You only need one clip per vehicle. You remove (Break off) the correct pins on this "clip" to set the calibration. A chart in the manual lets you determine which pins to break.

GM part Number 25085993 is a package of 20 clips

These parts are no longer available.

I discussed this with & Tommie at this board in great detail. Here is a link.
http://67-72chevytrucks.com/vboard/s...d.php?t=312063

Here is a link to a write-up Tommie did that is the best write-up on this issue that I know of.
http://67-72chevytrucks.com/vboard/s...d.php?t=313815

Links from Tommie’s write up:
http://www.koolcartoons.com/lowdown/...91cluster.html

http://www.454ss.com/Articles_new/tweek/DASHB.asp

http://67-72chevytrucks.com/vboard/s...d.php?t=178366

http://www.fullsizechevy.com/forums/...odometers.html

http://www.someotherplace.com/guides...p/cluster.html

http://www.tbichips.com/drac/

http://67-72chevytrucks.com/vboard/s...d.php?t=312063

http://614streets.com/drac.html

http://www.philter.com/cgi-bin/drac.pl


I you have any more questions I will do my best to walk you through a recalibration.

The shift indicator cable connects to the right hand side of the plastic part just below the part that the shifter is connected to on the column.

[tommie]

i was about to post that chevy tech!!!

hahaha...

[ChevyTech]

I save a link to your write-up and will send people to it for years to come.

It is a very good, and full of information.

Thank you for taking the time to make it.

[tommie]

no problem....

thanks for all of you help with everything chevytech...

[ChevyTech]

You're welcome!

Now if I can just get all my typing, spelling, and grammar errors under control!

Originally Posted by ChevyTech

I save a link to your write-up and will send people to it for years to come.

It is a very good, and full of information.

Thank you for taking the time to make it.

I saved a link to your write-up and will send people to it for years to come.

It’s very good, and full of information.

I the vehicle did not have the same rear axle & tire size from the factory the speedo would need to be recalibrated to read correctly in your vehicle.

If the vehicle did not have the same rear axle & tire size from the factory the speedo would need to be recalibrated to read correctly in your vehicle.

That’s better.

In my defense, I have been traveling with very little time to spend writing here on the board. If have rushed my replies.