87 suburban speedo problem, any suggestions?

[Nodnarb76]

My 87 suburban 2wd with Th400's speedometer hasn't worked since I got it.
I have replaced the cable(s) and driven gear already. Once I replaced the driven gear, it worked for about 7 miles then stopped. Every once in a while when the truck is cold (first startup of the day), the speedometer works for a mile or so then stops.

When the driven gear was replaced I had my friend at work do it ( work at a dealership) and I didn't ask him to check the drive gear inside the transmission.

I seem to have some sort of adapter between the cable and gear housing (see pics), anyone know about it and if it would be likely to fail?
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[Nodnarb76]

Update removed the adapter between the cable and trans.
Works great now!
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[68Timber]

That adjusts the speedometer cable rpm so the speedo reads true. They work great until they freeze up solid and break a tooth when you go to drive it. You can remove it and bypass it but the speedo will be off. Check the speedo against a GPS to see where you really are at a few different common speeds.

[Nodnarb76]

Haven't had a chance to check and see how off it is. Seems to be pretty close.
When I ordered the driven gear, I ordered the gear for 32" tires, 3.73 rear end and 17 teeth on the drive gear. according to what I have read this is the correct drive gear for what I have and may not need an adapter. I'll report back when I know for sure.

[68Timber]

You should be good without the "compensator" if you changed the driven gear to what you need for your combo. How did you verify the drive gear?

[Nodnarb76]

There was a website I found that had it. I stumbled upon it when searching around for speedometer problems. Sorry can't find the link.
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