Noise and slight jerk when downshifting from 2nd to 1st
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From: Hawaii
Noise and slight jerk when downshifting from 2nd to 1st
47k miles 2010 XK,
when downshifting from 2nd to first especially when going down hill,
and especially when the car is hot and been driven aggressively,
I can hear and feel a clunk almost like somethings loose suspension or a loose transmission mount,
any advice on what to look at first?
when downshifting from 2nd to first especially when going down hill,
and especially when the car is hot and been driven aggressively,
I can hear and feel a clunk almost like somethings loose suspension or a loose transmission mount,
any advice on what to look at first?
Last edited by trkyam; Jan 5, 2019 at 08:22 PM.
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Senior Member
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From: Hawaii
How much lash is acceptable?
Should this be checked while in P?
When i push my car I can roll it a couple inches while in Park back and fourth
Should this be checked while in P?
When i push my car I can roll it a couple inches while in Park back and fourth
Last edited by trkyam; Jan 5, 2019 at 08:54 PM.
While in park and one rear wheel off the ground, slowly turn it back/forth look for diff motion but no drive shaft motion. You might also hear unusual clunk/grind sounds from the U-joints if they are at fault.
As CeeJay suggests it could also be mounts or bushings as well.
As CeeJay suggests it could also be mounts or bushings as well.
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From: Hawaii
Sometimes in my condo garage the trans automatically goes to 1st in sport mode.
also the lovely pops and cracks when coming to a stop light
also the lovely pops and cracks when coming to a stop light
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it does, but not til Im at near standstill. And thats for take off purposes. In manual mode you have to drop it to 1st when at a complete stop. It will only go as low as 2nd. The reason is 1st is too short, and if I have to make a left or right from a standstill, I dont have to shift into 2nd mid turn, because the paddles are stuck to the upside down or spinning steering wheel. 2nd can handle take offs just fine, but if you want to launch, 1st is your friend. I dont use Sport mode because it downshifts too aggressively too often. I use manual mode, and I do mostly upshifts. If Im going to stop, I slow down and the computer will drop gears without downshifting(nicer on the Viscous clutch) once I stop, I will downshift to 1st for take offs, but never if Im going to turn. I will drop into 2nd if Im going to make a turn at an intersection, while at speed. Dropping into first while at speed is just too much wear and tear.
Last edited by Brewtech; Jan 6, 2019 at 05:11 PM.
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Ahhh, easy fix. Dont use Sport mode while doing non sporty driving such as exiting your garage. If you need 1st, select it manually and ride the way down. Shift up around 2k rpm, or switch to auto, and warm things up. The real challenge is to learn to shift and think ahead, when using paddles, and you can avoid needing to shift while the steering wheel is spinning. Ive gotten real good at it because sport mode doesnt do it for me. The shift points dont match what my mind is thinking, and the downshifts, as fun as they may sound, theyre simply at the wrong time. Use the paddles instead. Im going out on a limb here, but 1st is not for engine braking, unless youre tracking it, and are prepared to lose it all. Thats my approach to aggresive shifting and/or racing, and its what kept me sane when I money shifted my cup car. Live and learn.
Last edited by Brewtech; Jan 7, 2019 at 05:45 PM.
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I'll have to try it as I don't ever remember using sport mode.
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Transmission fluid has a life, and how it is used decreases that life.
Its hard to know for sure based on what you say.
The fact that it is "when hot and driven hard" inclines me to believe it is fluid related.
Wear in driveshaft's would be evident when cold.
Its hard to know for sure based on what you say.
The fact that it is "when hot and driven hard" inclines me to believe it is fluid related.
Wear in driveshaft's would be evident when cold.
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It seems to be a misconception that the car defaults to starting in 2nd gear. I can assure you, at least on my 2007 model, whether in D or S mode, it always starts from 1st at a stop. All you have to do is count the shifts to 6 to realize it!
To the OP, when you say clunk do you mean like a clicking/popping sound? I have had this noise ever since I bought my XKR, most evident when lurching slightly when paddle shifting and/or getting on and off the gas in manual mode while at mid to upper RPMs. Nobody seems to have figured it out.
To the OP, when you say clunk do you mean like a clicking/popping sound? I have had this noise ever since I bought my XKR, most evident when lurching slightly when paddle shifting and/or getting on and off the gas in manual mode while at mid to upper RPMs. Nobody seems to have figured it out.
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On my 5.0 XKR, always going to 1st would be unpleasant and unnecessary.
I have found it depends on how much throttle I apply. In other words I have to request the 1st gear.
