Hey guys, need more data....as some of you have been watching, commenting on my 6.0 from a 94XJ12, going into my 89. Well, because I happen to have a couple of 5 speeds, and a dual disc custom clutch, as well as a aluminum flywheel, and now a pedal box on its way for a Teeves III car, I am itching to switch.

The problem is my trans. I purchased these from a retired Eaton engineer, that was clearing out. One of them is NOS, never installed, the other he claimed had less than 3K miles on it. I've had them stored in black plastic bags for quite some while.

The glitch is, I can't identify them. They both are Tremec 3550 trans. They both have large, almost square plates bolted to the top, one in front of the other, then a narrow rectagular plate, then the shifter. one measures almost 24" from face of trans to shifter, and the other is about 20". I have googled pics, and can't find anything like them. I tried to decode by the trim tags, but even that seems to lead nowhere.

I took pics, and wrote down the lettering on the ID plates

I could download pics if I knew how. I know it sounds stupid, but using one of these transmissions is a deciding factor, as I am trying my best to not spend a penny more than I have to, on a toy I know is a loser financially. I have the 460LE from this XJ12, along with the wiring, and computer, so I am not opposed to that. Its just that I'm a little disappointed to find that the 400 and the 460LE have exactly the same gear ratios until it gets to 4th, and the lockup TC make a difference. I am looking for a more fun car, with better low end pull, than a highway cruiser.

I put almost 70K into my dream V12 XKE, only to have to sell it 2-3 years ago at a HUGE loss. The XJS is not a XKE, but hey, it is a good looking V12 Jag. Any help appreciated.