Lately my car has started to stutter round 40mph under light power conditions. When I more aggressively press accelerator the stutter stops. I do not notice any unusual sounds from engine nor transmission. And there are no leaks on garage floor. It is the AWD model.
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Have you replaced any tires recently??
Have you checked your tire pressures recently and corrected if needed??
Try just depressing the brake pedal hard enough to turn the brake lights on but not slow the vehicle any with your left foot to see if it affects the shutter…
Have not replaced tires and I routinely adding air as the tires do loose. Have tried depressing brake pedal and think I feel a bit lessening of stutter. Will continue to evaluate. I appreciate the response as I never considered brakes. Am most concerned of transmission problem. If indeed brakes does it pose a hazard?
When was the last time the transmission fluid/filter was serviced?
What you might be feeling is torque converter clutch shudder.
.What Causes Torque Converter Shudder: Comprehensive Guide -
Tester
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This seems at odds with what I feel in the car. When accelerating normally, I do not feel a shudder, it happens under light acceleration. What sort of shop should I consult?
You didn’t answer the question.
Tester
I have had the car for about a year and has not been done since I got it. Has round 115,000 miles. So I guess that would be first action.
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The test was not checking the brake, but was a common test for torque converter shudder, typically when you depress the brake pedal enough to turn the brakes lights on, you command the TCC (torque converter clutch) to disengage, so if doing the test I mentioned stops the shudder, then you most likely have a TCC shudder or an issue with the TCC locking up to early or whatnot…
When you more aggressively press the accelerator pedal the stutter stops due to the TCC disengaging…
You can try changing the ATF with the OEM fluid NOT a universal ATF and add a tube of Lubegard Instant Shudder Fix…
Do you have a CEL (check engine light) on?? check anyway to see if you have any pending codes…
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No engine light on. How would I check pending codes? Is this an early transmission failure/leading to one? I do seem to be noticing it more last couple days.
Thanks for all the advice.
Don
Same way, it might require a better DIY scanner though (maybe), but I think places like O’Reilly normally uses the best scanner they sell to check codes… Of course there might not be any…
Not always, when I was still working for a trans shop, we often would service the trans and add a tube of Lubegard Shudder Fix and it would solve the issue, I had done this before and after working for said shop over 35 years…
Fluids break down over time and lose the additives that make them unique to your transmission’s needs. The only way to get that back is with fluid changes. One reason to never use universal fluids (ATF)…
On top of a fluid (ATF) issue, yes you could have a bad torque converter and or uneven TCC surfaces and or poor module command (TCM) or issues with the valve body…
Basically, if the ATF change with Lubegard doesn’t help, then you need a pro trans shop to be able to properly diagnose the issue, lot of possible issues for TCC shudder…
Given that the age / mileage on the transmission fluid seems to be unknown, I would suggest finding a local, reputable shop that specializes in transmission work. (No corporate chain operations such as AAMCO). They’ll often have reference to transmissions in the name of the business.
Bring it to them for an evaluation and fluid change. They will absolutely have the scanning capabilities needed. Even if it’s not torque converter shudder, having the fluid/filter serviced is just a normal maintenance thing that should be done.
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