I'm convinced that my transmission is original to the car. If you discover a revelation, please let us all know. Almost everyone remarked that they had never seen such numbering and no one owned up to understanding the ID including some who had worked at the Triumph factories in the 60-70's. I got mostly quizzical reeponses from most. When I discovered that my tranmission ID # did not match the conventional numbering, I queried several sources throughout the LBC world. to see if I could find Identificaton # somewhere else on tat trans. I'll remove transmission tunnel next W.E. I've asked the question around and nobody is familiar with those #'s. The number of and layout of the interupts on the top of the tranny will help norrow down its' age. TR6 V8 pic attached just for laughs bought that gearbox from the owner of this piece of work. If anybody identifies yours or mine I'd be very interested in hearing from them. It is a Stanpart box and looks identical to all other TR6 boxes but that is not a TR6 box number or a TR4 box number. I too have an odd gearbox with # CT78323. I have no clue what you have there and I can't find a reference to a D series anywhere. I can't remember where I read it from but I jotted it down when I redid my transmission in 2008. It is on a 69 TR6 and I know it is original. I have the following serial number on my transmission.

My D 21 E 71 is a 1971 TR-6, manufactured in June 1971 (so almost a 72!!). As I am doing a major overhaul of my TR6 I will inspect transmission and knowing which model year is a plus. I am still without knowing if it is a 75's trans. If you can contribute to understanding this please do! Thanks. My comment,, Gearbox Serial Number.my number is D 21 E 71. Asked several sources about that number and no one would own up to recognizing anything about it. Can't check right now, but as I recall, the number did not fit anything and may well have been D26 L. I think that I may have the same number as you. Search the archives for a note from me on this subject.

I never did find a number stamped on my tranny. Unfortunately there is noting there except D26 L, which is not suitable.ĭid someone ever noticed that number stamped in another place on trans? I need to find that transmission identification number usually stamped on left boss near clutchshaft. Triumph TR6 - TR6 1975 transmission identification # Hello,

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