PerpLexusd

Let me start with a little bit of back story, I have a 92 LS400 with well over 300K on it and a few years ago around 240K I decided it would be a good idea to do a full flush on the transmission since the fluids never been changed since I've had the car (late 90's early 00's). Needless to say that was a BIG mistake. The transmission started slipping and disengaging the gears and just got worse, I managed to make it work over the years by replacing most of the fluid with Lucas transmission fix. It worked surprisingly well kept the car going for a few years. Well the other morning on the way to work it finally gave out, I don't know what happened but it made a big clunk and stopped moving.


So here's my question I found someone selling a 5 speed automatic transmission out of a 98 SC400 for cheap locally. Will the transmission swap wit mine pretty easily or will it fit at all? Has anyone ever done this? I don't want to do the 5 speed swap that seems to be getting popular I just want to drive down the road again with a little more pep. Also should I ask this in the SC section also?

LScowboyLS

I don't know about swapping transmissions, but if I had a dollar for every time I have heard of someone doing a transmission flush of any kind and subsequently having a problem, I'd be rich!

it's drain and fill for me (do drain and fill enough times over the years and you have mathematically flushed the transmission, albeit safely!)

PerpLexusd

Yeah I wish I'd knew that back then

JBrady

While it is theoretically possible it is NOT practical or inexpensive or in any way easy.

Either find the correct replacement or rebuild the one you have.

Yamae

They are not interchangeable. A 92 LS400’s ECU is not deigned to control a 5 speed automatic transmission. As modern engines are controlled by the electronics circuits, so are the transmissions. You need an ECU for a 5 speed automatic transmission but it cannot handle the engine for a 92.

PerpLexusd

Well those were not the answers I wanted to see. I know by comparison they'd swat out physically but I was wondering about the computers. I hoped it would work but I guess not, looks like ill be searching a different route...

PureDrifter

iTrader: (10)

lol what makes you think a trans from 2 versions later of the same engine would just bolt-on and plug in and work fine?

just buy another of the same trans, they're a dime a dozen at junkyards. <$400-500 all day long. (WAY cheaper in socal too )

PerpLexusd

Hopes and dreams really, the transmission was only $100 so I really wanted it to fit. I'll probably just rebuild mine seeing as I can buy a rebuild kit for around $600 or buy another 20 year old transmission that might be just as bad for a few buck cheaper.

So my next question is are there any good rebuild kits anyone would recommend? I found some level 10 rebuilds but the reviews say they are no good. So now I'm looking at some import performance transmission (IPT) rebuilds, but haven't seen much on the reviews for them. Any other suggestions?

mikes7ke

iTrader: (1)

$400-$500? Ouch. There's a yard around here with three 90-94 LS400s and last time I was there each one still had a transmission. Transmissions go for $60 and torque converters go for $20.