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TR2/3/3A Which TR3 tranny is this?

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PeterK

PeterK

Yoda
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After reading the TR3 Transmisison Blues thread (phew), I just had to check my spares. I've got 3 - 306812 SM, two of which have a longer input shaft (4A?) and one 250 I think because it has a reverse switch on the top of the cover.

But then there's the TR3 tranny 302551 that came woth my 4A. Which 3 is it from? And is it synchro? Has the filler plug, no dipstick.

My 3A came with one of the 306812 SM trannies and the long shrouded starter but now has the HVDA with a 4A flywheel and TR6 B&B diaphram plate.

Anybody have a reference on the 302551? PeterK
 
Peter, My guess is that the 302551 might be the early 4 and 3B trans case. It's not listed in my TR2/3 parts book and I don't have a 4 parts book. However the 306812sm is the 4A trans case. You can easily tell the non from full synchro transmissions by the reverse gear bulge on the lower drivers side of the case on the full synchro transmissions. What is the serial # on the 302551 case? That's the easiest way to tell.
Tom Lains
 
Thanks Tom,
No buldge under the speedo cable so non-synchro. Serial number is 13 A 607 - the "7" is barely visable and might not be part of the serial. The rest is very clearly stamped but I would have expected a TS prefix. Peter
 
I had the same question early this summer when I was swapping trannies and getting O/D into my TR4A. There are some late TR3A (maybe even early TR4) boxes that have the long started bulge but are non synchro (in first gear). That is what I had (not knowing so). But when I opened it (and the TR3 short bulge box that I was taking the O/D from) up I was able to confirm that it was a non synchro box with a long starter bulge.

If you would like (send me an email to remind me please) I can look up the serial number from it tonight and see how close to yours it is. I suspect there were not that many like this.
 
What I learned

Never knew about tranny numbers before, still learning too

The TR3 tranny is marked 13A60, no TS serial# on it; was made on Jan 13,1960 so it puts it squarely in the middle of the 3A production, still non-synchro, but has the bump for the later unshrouded starter.

The 2 TR4A trannies are 1965 and 1966 by their "born on" date below the serial numbers. The 1965 one came our 1958 3A with a shrouded starter nose.

The TR250 was made 8K67 (Aug 11,1967) serial #CD1392 so it's an early TR250 production one indeed.

Thanks for the lesson. PeterK
 
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