Hello all,

I have a 2006 LS430 with a low mileage transmission (roughly 60k) that was just installed about a month ago after the dreaded P0761 and "stuck in 3rd gear" issue.

The car drives fairly well 90% of the time, but I've noticed the transmission tends to be a little clumsy when shifting gears at times. It also seems to be that the longer the car is on the more it stumbles into this issue. 1st-2nd gear can be fairly noticeable at times, but the biggest issue being 5th-6th gear slightly jerks when I'm just cruising at a steady speed of around 45-55mph.
The ECU was sent off prior to the transmission replacement for a rebuild by Relentless Mottorsports (one of the worst experiences I've ever had with a business) so I'm curious if it could just use a better rebuild by SIA or if this is a normal or common problem with these transmissions. Any help or insight is appreciated.

 

Relentless has a great reputation. What happened with him?

 

He lost my ECU twice, consistently made excuses as to why work wasn't getting completed (he had the ECU for nearly 2 months), he was incapable of creating a business invoice and wouldn't payment aside from Zelle, Cash App, or Walmart to Walmart. I have 4 other people in a group who have all had the same issue with their cars and same experience, and after promising he could fix the 3rd gear issue "because he was the one that discovered how to fix these LS430 ECUs" (his words not mine) that it would be fixed when I received it. Nothing changed, and upon overpaying and questioning him on what he fixed andwhat he discovered he couldn't give me an answer at all and blamed the issue on me and my business.