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TR2/3/3A To j type on not to j type

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Got_All_4

Got_All_4

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That is the question. I recently acquired a J type trany from a 1973 or 4 TR6 for my TR3A. I've been following a lot of the questions about if it was even possible to fit a J into a 3 and I see a lot of you have done it. My dilemma is I also have a 69 TR6 with a A type in it and no where on the vin tag is there a O that would designate a factory overdrive install. Not sure if I'm correct here? So, debating on whether to install the A in the 3 and the j in the 6? I just ordered the build certificate for the 6 to see if it came from the factory with a overdrive and that would be the deciding factor if it did. If not what would you do?
 
I couldn't stand it, knowing I had the right tranny for each car. Make the swop and we both will feel better. LOL

Wayne
 
The 69 TR6 would have had an A type in it as well. The j type was not fitted to the TR6 until 1973.

Cheers
Tush
 
If the factory installed the OD, then there would be an 'O' on the end of the commission number. However, they were sometimes installed by dealers (who were not allowed to add the 'O' even if they had wanted to), so the OD may still be "original". Or not.

If it were me, I'd sell the J type and buy another A. I own both (both Stags have J types, the TR is an A type), and the A is a lot more fun to drive, IMO.
 
12 hours later and I just got out of the basement from cleaning it up to disassemble the J type tranny down there. This wheather is getting crazy around here as we just got another 6 inches of snow today. Hadn't seen grass since December. Too cold to work in the garage so everything is coming in. For now the A is staying in the 6 as the temps are to stay below the 20s for a few more weeks. Got to love Ohio. Anyway thanks for all the replies.
Randall you say it's more fun to drive the A types. is that because of the more gear selections and is it possible to do the same to the J type without major surgery? Basically I just wanted the overdrive for 4th gear to keep the revs down on the highway. No hills or windy roads around here so little chance to use the in between gears. Now when i go to the TRF Summer Party and do the mountain tour there were times I was shifting back between gears to find he right speed and whished I had the OD then. But that's once a year.
 
Got_All_4 said:
Randall you say it's more fun to drive the A types. is that because of the more gear selections and is it possible to do the same to the J type without major surgery?
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Yeah, basically. 2nd OD also seems like it shaves a tenth or two off the 0-60 time, but maybe it just seems that way.

But I don't think you'd want to hook a J-type up that way. The A-type keeps an accumulator full of oil under pressure, so it shifts into OD practically instantly. But the J-type has no accumulator, so it relies on the pump to move enough oil to move the clutch ring from the direct drive to the overdrive position. And the pump runs at driveshaft speed of course, which is pretty slow in 2nd gear. Even at 70 mph, the shift is slow enough to annoy me after driving the A type. There are ways to speed up the shift, but I don't see any practical method of ever making it as fast as an A-type.

PS, these things work surprisingly well in a cold garage. The radiant heat will warm your clothes and skin even if it can't get the air very warm.
https://www.tractorsupply.com/en/st...-radiant-certified-tank-top-heater-30000-btus

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