Tach Cluster Question - Need Part Number Information

[Evil Trailblazer SS]

So, the tach cluster I bought as a few broken tabs and all that...plus it was a pre-84 unit that was modified at the speedo so the speed buffer was able to be connected. Through my research, I found that this cluster case's part number is 25017375. I found a brand new one at a dealer. I will purchase this one if I am forced to, but I do not "want" to modify a cluster case to work. I'd rather try to find the right case.

I found another part number for a supposed similar case (25044310) but I cannot find any info other than what my GM parts guru buddy said. He said this part number is called out for the same vehicles and same model years as the 25017375 case (1979-1984).

Since the speed buffer speedo (electronic cruise control) was offered starting in late 1983 production AND tachs were offered up until 1986, I would like to find the correct instrument cluster case for my truck (1987 V30 WITH Cruise/has speed buffer) if it were built with a tach from the factory.

Can anyone help?
Posted via Mobile Device

[80SPORT]

Last year for factory tach in 10 to 30 series trucks was 1981.....

[Evil Trailblazer SS]

No, it wasn't...The basic order form did not list it, but there are many documents that show you could get one and some people did get them after 1981. Heck, there are even a few out there with tachs from 1987 model year.

The printed circuit part number 25044898 calls out 10-30 series trucks from 1981-1986. The 25044310 AND 25017375 cases are called out for trucks up to 1984 model year (change over to speed buffer speedo) and the OEM small fuel gauges are called out up 1986 model year as well. These are all specifically for tach equipped 10-30 series trucks. So tell me how (logically) you can say tachs were not available after 1981 when all of GM's histories and information says otherwise?
Posted via Mobile Device

[motornut]

http://67-72chevytrucks.com/vboard/s...342926&page=25
Keith's 87 has one ,he's the one to ask about it

[Evil Trailblazer SS]

Originally Posted by motornut

http://67-72chevytrucks.com/vboard/s...342926&page=25
Keith's 87 has one ,he's the one to ask about it

Keith and I have chatted before, so I went ahead and sent him a PM regarding this because I am lost right now...it seems like the only logical answer is that GM modified the 25017375 cases by hand for the very few 84-87 trucks built with a tach...that doesn't seem very logical over all!
Posted via Mobile Device

[c10sport]

I pulled a tach cluster from a 1986 GMC C3500. The cluster housing had been cut out for the connector on the back of the tach unit.

You could get a tach all the way up to 1991, so I found out on Compnine before they went away. I'd LOVE to find one of those clusters if they had an electronic speedo too...It would save me from modifying my cluster for the elec. speedo but it would also take the fun out of it.

I doubt they modified the housings since the C40-80 big trucks could have a tach optional and those clusters fit the regular sized trucks, I'm betting they just grabbed one of those from the parts bins.