Myth or not? TH400 Tranny in our trucks

[toms68cst]

I’ve heard may folks here claim they have a factory TH400 transmission. I have the 68 resto pack and a lot of sales literature for our series of trucks. Nowhere is there any mention of any automatics other than the Powerglide or Turbo-Hydromatic. (I presume they are talking about the TH350.)

Was the TH400 really offered in these trucks or is it a myth? Who here can prove that they have a true FACTORY TH400 equipped truck and not the just a TH350 equipped truck? Did GM differentiate between the two automatics in their literature? What was the first year of the TH400? Was it available in all Light duty trucks or just the H.D. C/20’s and C/30’s?

I’ve been wondering about this for a while.