I'm having a little trouble with the sequentail transmission in my 2015 Exige V6 Cup R. I'm hoping to find some insight on this board as to what is causing the issue and if it's been seen before. Or a referral to someone who 'truly' knows Lotus's sequential transmission setup; Xtrac transmission with Shifttec GCU paddle shift control and actuation.
The car and transmission have been running great. Used for HPDE's with a little under 2000 miles now. I've recently run into the issue of the factory Xtrac transmission downshifting from 4th to 3rd, or 3rd to 2nd, on its own, without being told to do so. Obviously, this is unnerving when driving hard at high RPM's.
It seems to only do it on hot track days, 80+ degree weather, but on Friday it did happen on a 75 - 78 degree day. I thought it was happening because of high temps but the 75 degree day may have disproved this theory.
It doesn't happen very often, maybe one or two times per 10-15 lap session, sometimes not at all. It only happens on the downshift, it has never happened on the upshift.
Over the weekend, my friend, who also has a 2015 Exige Cup R, was at the event and his was running perfectly, no issues.
I spoke to Xtrac USA about it, they were very helpful, great service, though it seems clear this isn't an issue with the gearbox itself but an issue with the paddle shift control unit/actuation unit/GCU which is made by Shiftec. I have yet to get Shiftec on the phone. Lotus North America and Lotus Motorsport are none existent, I've emailed and called them both with no response.
If anyone has any real insight, or a very solid referral, it would be very much appreciated.
I've added a photo of a basic heat shield we put next to the GCU to try to shield it from some of the heat created by the transmission. It seemed to do the trick at first but issue has came up again over the weekend.