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General Site Info => General Discussion => Topic started by: johnboy3927 on August 07, 2015, 09:36:34 pm

Title: 1984 k10 transmission questions?
Post by: johnboy3927 on August 07, 2015, 09:36:34 pm
Was there ever a 3 spd automatic made by gm with overdrive? I am looking at buying a truck on craigslist and the owner says it has a 6 cylinder with a 3 speed with overdrive. Never heard of an overdrive tranny until the 700r4! Any help would be appreciated to see wether this guy just doesn't know what he is talking about or is a scammer!
Title: Re: 1984 k10 transmission questions?
Post by: Irish_Alley on August 07, 2015, 10:06:39 pm
some miscount the gears like the sm465 some say 3 speed with granny some say 4 speed and they both are right in a way just depends on how old you are. 3 speed+OD would be 4 speed (700r4)
Title: Re: 1984 k10 transmission questions?
Post by: zieg85 on August 07, 2015, 10:13:53 pm
3 speed with overdrive could be the elusive NP 833 manual transmission.  A rare find indeed.
Title: Re: 1984 k10 transmission questions?
Post by: Irish_Alley on August 07, 2015, 10:29:11 pm
forgot about the manual lol
Title: Re: 1984 k10 transmission questions?
Post by: enaberif on August 07, 2015, 11:53:02 pm
While not necessarily overdrive you could get a TH350C with a lockup converter.
Title: Re: 1984 k10 transmission questions?
Post by: LTZ C20 on August 08, 2015, 03:14:04 am
While not necessarily overdrive you could get a TH350C with a lockup converter.
This, there was the TH350C, no its not an actual extra gear, it's a lock up converter but that's still in over drive. Saying the 350C doesn't count as over drive would be like saying that the 700 R4 has 5 gears not 4. The converter isn't a gear, it does however drop the rpm's, allowing for better mpg and blah blah blah.

If it's an auto 3 speed with OD, it's either a 350C or a misidentified 700R4. If it's a manual 3 speed with OD, it's a 4 speed. (Whether you prefer 3 speed with granny low or 3 speed with OD like Zieg mentioned.)

Like Irish said, depends how old you are haha.
Title: Re: 1984 k10 transmission questions?
Post by: Irish_Alley on August 08, 2015, 03:24:33 pm
maybe its my ignorance but i dont follow how the th350c could have OD. if its really a gear over drive (1:1) then locking up the tc would just be 1:1 since the 3rd gear is 1:1.
Title: Re: 1984 k10 transmission questions?
Post by: Jason S on August 08, 2015, 05:45:49 pm
For an 80's GM truck with an automatic 3-speed with overdrive, I'm thinking 700R4...