strange transmission noises lesson

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jdlmodelt
Scoobytruck Contributer
Posts: 44
Joined: Sat Dec 12, 2015 12:59 pm
Location: SW Colorado

strange transmission noises lesson

Post by jdlmodelt »

I thought I'd share this interesting learning for the mechanics on here.

Our 2013 Honda CR-V started making clunking noises that occasionally sounded like there was a hand full of marbles in the transmission. There was the occasional clunking sounds and excessive vibration and cabin noise. I thought the transmission was about to blow up. Jacked it up, spent a couple of hours underneath inspecting everything I could think of, including verifying the torque converter bolts were all secure since the engine was idling rough when the transmission was engaged in Fwd or Reverse. Took it down the road and at some point I drove over some bumps and the noise got worse, thought the tranny was going to crater before I could get back to the house. Jacked it up and inspected the underside one more time and finally spotted a rock wedged between the unibody frame and the cast aluminum engine oil pan. That was it. the Rock grinding and clunking sounded like a hand full of marbles in the trany. One to remember for the books. Hallalu! I thought we would be leaving the car in the shop for a month for a new trany.

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anarchy1024
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Re: strange transmission noises lesson

Post by anarchy1024 »

How did the rock cause the rough idle and the other problems when in gear?

jdlmodelt
Scoobytruck Contributer
Posts: 44
Joined: Sat Dec 12, 2015 12:59 pm
Location: SW Colorado

Re: strange transmission noises lesson

Post by jdlmodelt »

since it was caught in a "V" like valley between the aluminum oil pan and the car sub frame, it was a rigid connection between the natural vibration of the engine and the car body/sub frame. Engines and Tranys are all rubber mounted on these cars to eliminate/minimize the noise and vibration from the engine and transmission to the body, so, when it was engaged in gear with slight engine rocking that occurs and added vibration due to the engine loaded with the transmission in gear, the rock would grind and transmit noise and vibration and make strange squeaking and knocking noises as it was rubbed between the engine and frame/body.

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