Transmission issue

[robinlarry]

During a session at MidOhio Race Track, I lost second and third gear. Nothing. Then they came back. Then gone again. I returned to the pits and observed the same happening again. I would have all five gears. Then I would lose them. Then back again. I installed Callahan's short shift kit several years ago and have not had a problem since. New lightweight flywheel and clutch and Quaife and no problems before the track event. Fluid drained with no shavings present. Thoughts?

[dapinky]

I know of very few (probably zero!) instances of gearbox failures on these cars - but it doesn't mean that they have never happened.

The only common 2 failures are due to the cable(s) going bad and the 'stuck in 5th gear' issue - neither of which apply here. If it were the cable(s) then it would affect either 1,3,5 OR 2,4,R depending on which of the 2 had slipped.
To affect 2 & 3 suggests that it is something mechanical inside the box on that particular shaft (possibly a stripped or partially worn gear/sincro ring/whatever) which is something I've never delved into.

Hopefully, someone will have a clue, but in the meantime, I would suggest reaching out to the Isuzone.org forum as the gearbox is the same as used in the Impulse/GEO Storm/Asuna Sunfire and they may have seen it before.

There is a pdf document (titled:- Gearbox rebuild) that I put in the manuals section on stripping and rebuilding the gearbox, so that may give a clue as to possible causes.

[robinlarry]

isuzone.org appears to be gone. Thanks for the information on the gearbox.

[TorqueHorse]

They still have an active FB group and also a Discord server
https://discord.gg/d98RGrwW