Looking for any pointers to an issue with my vehicle.
I have a 2015 Lexus RX350 AWD. Raising this in the Highlander forum since the Lexus RX350 and Highlander share the same platform.
My vehicle has run 145k miles and is driven year-round in NJ. Around 3k miles (3 months) back, the vehicle has started to "buck" at around the 15mph mark when accelerating from a stop. This happens every time when accelerating from a complete stop including traffic light stops. It happens for 1 second and then the car is normal again. The feeling is not a noise, but a physical sensation of the car jerking and then going back to normal, as if there is a momentary surge. Issue happens during accelerating and does not happen when decelerating.
Check engine light is not on. No adverse lights in dashboard. Transmission fluid has never been changed. Fully synthetic engine oil has been changed every 10k miles (Lexus recommendation) except the last 2 changes which were done at 15k miles. Issue started at around 13k miles without an oil change. The problem started in winter but with warmer weather in the 60s now, the problem continues. I fuel the car usually at Costco, so the fuel quality is good.
It seems to me that the bucking happens when the auto transmission is shifting from Gear2 to Gear3. An interesting observation is that if I take the foot off the pedal at around the 10mph mark as the vehicle continues to speed up from the initial pedal input, the jerking sensation is not there as the vehicle goes thru the 15mph mark. Also if I floor the pedal from a stop, there is no jerk at the 15mph mark. The issue happens around 15 mph with a standard medium/light touch on the pedal when starting from a stop.
I got a code reader (Bluedriver and Veepeak) and there were no codes for the engine, transmission, fuel system etc. Did 2 cycles of fuel system cleaning using Techron and that hasnt helped.
Would be glad to hear of possible reasons why this is happening. So far, I have got suggestions for changing the transmission fluid. But the specific symptom of the issue only happening at the 15 mph mark and that too not occurring if I take my foot off the pedal or if I floor the pedal leads me to believe it is not a standard transmission issue or a shift solenoid issue.
I have a 2015 Lexus RX350 AWD. Raising this in the Highlander forum since the Lexus RX350 and Highlander share the same platform.
My vehicle has run 145k miles and is driven year-round in NJ. Around 3k miles (3 months) back, the vehicle has started to "buck" at around the 15mph mark when accelerating from a stop. This happens every time when accelerating from a complete stop including traffic light stops. It happens for 1 second and then the car is normal again. The feeling is not a noise, but a physical sensation of the car jerking and then going back to normal, as if there is a momentary surge. Issue happens during accelerating and does not happen when decelerating.
Check engine light is not on. No adverse lights in dashboard. Transmission fluid has never been changed. Fully synthetic engine oil has been changed every 10k miles (Lexus recommendation) except the last 2 changes which were done at 15k miles. Issue started at around 13k miles without an oil change. The problem started in winter but with warmer weather in the 60s now, the problem continues. I fuel the car usually at Costco, so the fuel quality is good.
It seems to me that the bucking happens when the auto transmission is shifting from Gear2 to Gear3. An interesting observation is that if I take the foot off the pedal at around the 10mph mark as the vehicle continues to speed up from the initial pedal input, the jerking sensation is not there as the vehicle goes thru the 15mph mark. Also if I floor the pedal from a stop, there is no jerk at the 15mph mark. The issue happens around 15 mph with a standard medium/light touch on the pedal when starting from a stop.
I got a code reader (Bluedriver and Veepeak) and there were no codes for the engine, transmission, fuel system etc. Did 2 cycles of fuel system cleaning using Techron and that hasnt helped.
Would be glad to hear of possible reasons why this is happening. So far, I have got suggestions for changing the transmission fluid. But the specific symptom of the issue only happening at the 15 mph mark and that too not occurring if I take my foot off the pedal or if I floor the pedal leads me to believe it is not a standard transmission issue or a shift solenoid issue.
