Story
I had to rebuild my r154 2 times for various things. THe fact of the matter with these transmissions is that it is a (now) a 40 year old design. A gear box is a gear box, I get it, and this is a good one built to a higher standard and strength than ever necessary for its applications.
I ran into issues getting parts and more recently anyone to even bother working on it. So I had two options, get a new trans or learn how to rebuild the box myself.
My gearbox is a 1990 Supra Turbo box, I used a 1jzgte bellhousing and flywheel with a 7m clutch disk and pressure plate. a lot of manufactures can make or already have clutches for this kit. I have used 1jzgtw clutch kits as well. I did modify the box with teh help of Aaron and old drift motion crew for the custom welded extended shifter housing to work with my IS
Parts
Most parts are now available through Drift Motion for internal gearbox stuff and clutches. This is great, i got all parts from these guys and they were prompt and as always, just great people to work with. The next helpful place is marlin crawler. since these boxes were used in 4runners, they have an excellent selection of upgrade parts and maintenance parts.
Clutch
I am working with an IS300, a 2jzge VVTi block, i used a 1jz bellhousing, a 1jz clutch configuration, I am using a 7m pressure plate and disk that’s highly modified to hold 700-800 ft-lbs of torque. The guy though that made them has since retired and I am nervous for the next clutch I need.
Rebuild
There are a ton of resources, manuals, and videos on how to rebuild these boxes. Some are great, others vague, but the big things i have noticed is you need a significant toolset that i do not posses. I called a dozen transmission shops in the Atlanta area and none would touch the gear box, not sure if it was because parts availability or what. If this is goal of yours to use this box know that you could be on your own for support and there aren’t a lot of boxes floating around out there. I was able to find a shop (a local shop) that did not have problem, they tore it down, i ordered parts they needed (which was nearly all of it) and they put it back together, got me a new clutch, and replaced the transmission for me which was great. The original quote for R&R+reman was under $1k which i was excited to not have to deal with pulling the trans off on my own on my back.
