thoraxe

Grenaded the W58 in my SC300 and am probably going to buy a used JDM one. I'm just curious about rebuilding the gearsets in the one that I have. I've found a few bits and pieces on various transmission sites but they mostly seem focused on the trucks (eg: Tundra). It's not clear whether or not the various gears and shafts are compatible. Things branded "rebuild kit" are usually just seals and synchros and bearings (no gears).

Anyone know of a parts/rebuild source that has not just the bearings and seals but all of the gearsets? Or perhaps has a diagram of the parts and part numbers? My Google-fu seems to be lacking.

KahnBB6

iTrader: (5)

Try partsouq for exploded diagrams of the W58. That's the best way to see what internal parts Toyota even lists for this transmission. They have factory exploded parts diagrams and original part number listings from those original diagrams for a huge variety of Japanese vehicles in all world markets. Note that you should be very specific about yours as being a U.S. spec and also try to narrow down the model year and transmission listing for the overall model. You'll understand when you use their system.

MidLife

thanks. the seller got back to me and confirmed that it was from a 85 Celica GTS. im not sure if the thread i was reading for info is outdated or not, but there was a few people in there continually warning the OP sell his MK3 transmission and get one from a MK4 / SC300 because it just would not fit without extensive modifications.

any other info would help, thanks!

KahnBB6

iTrader: (5)

I think I remember that thread. I may have responded there. Fundamentally there is nothing wrong with a 1985 Celica GTS W58 but it's just not suited for an SC300 due to the significantly increased weight of the SC chassis versus that of the Celica/Supra MKII chassis putting extra stress on the weaker design of the early W58 (that's the most important problem), plus the added cost of the JZ bellhousing, custom trans crossmember solution, Marlin Crawler mechanical-to-electrical VSS adapter, and the need for an OEM SC W58 shifter extension housing or a custom extension housing.

All of those modifications are worth it if you are working with an MKIII R154 because it's a generally very strong and turbo friendly transmission that can take an excellent amount of horsepower and torque. With an MKIII W58 the ultimate safe power holding is even less than that of the SC and MKIV W58's and even putting one into a 3500lb 220hp SC300 or 250-260hp SC400 isn't sure to be reliable. With W58's the troubles people usually have are related to sudden shock-loading of the very small internal gearsets that a turbocharged engine gives. In the absence of turbo(s) the SC/MKIV W58's shouldn't ever break.

However the MKII & MKIII Supra and 80's Cressida W58's are not built as strongly as the later versions. They should usually be fine in a much lighter chassis than an SC. It's the weight of the car that adds more stress. This 1985 MKII W58 that you have was originally intended for an engine with maybe 150hp at most and the Celica chassis it came from couldn't have weighed more than 2800lbs (probably slightly less).

To find repair parts for it however I would use partsouq to look up the US-spec/LHD 1985 Celica GTS M/T. I'm not sure that the later W58 parts will all fit correctly-- you'd have to discuss that with a transmission rebuild shop. SpeedForSale in Alpharetta, GA rebuilds W58's (and R154's and V160's) and even offer a horrendously expensive PGS (I think it's PGS) cryo treated gearset upgrade for the later W58's. Jack's Transmissions may still rebuild W58's. Also Marlin Crawler of course. Any of them can offer an educated opinion on just how much can realistically be done to your '85 W58. The far simpler solution would be to just find an SC or MKIV W58 and swap that in. Out of the box it is stronger and designed to fit into the car as is.