Shifting up and down like 6-9 times and never hitting 4th gear would ruin your box IRL ( fight me IRL ) lucky the supra has that safety feature.
It is extremely important to acknowledge how the Supra W58 differs from the W57, which is mostly in its fifth-gear ratio. This transmission is popular as a replacement for weak stock transmissions in other vehicles. It came in two varieties: the original found in the 1982-1989 non-turbo Supras, Celicas and Cressidas of the early 1980s; and the later version found in Mk3, Mk 4 Supras and Lexus SC 300s.
Toyota lists a change from an alloy sandwich plate to a steel sandwich plate around 1989. The steel sandwich plate has some minor internal differences, and it is believed to be slightly stronger (some wider bearings, some wider gears, slightly different gear selection mechanism, etc.). In theory the all-alloy version of the W58 should be exactly the same strength as any other all-alloy W-Series transmission. The steel plate version is considered much harder to find and worth approximately three to five times as much as an all alloy version.
The ratios and bolt patterns remain the same regardless of the sandwich plate used.
The W58 & W57 share the highest gearing and closest ratios (1st, 2nd, 3rd, and 4th (direct)) of the stock W-Series transmissions.
The ratio shift was accomplished by taking the W55 base ratios and changing the input shaft to intermediate shaft ratio by 7.9%, thus shifting 1, 2, 3 ratios higher by that amount. This also shifted the overdrive 5th gear higher by the same amount creating a wider and taller overdrive ratio.
The W58 is sometimes designated as a "close-ratio transmission"; however, in its stock form it does not meet all the criteria for a close-ratio box.
Toyota engineers have shown favor to the W58 over the rest of the 'W' series by including it in so many models and even building a stronger version for higher powered applications.
