YACT: Car jerked hard on a downshift

[Red]

From a stop light, I was making a right turn onto a 45mph road. A car was approaching me quickly from behind when I was going 25mph, so I pressed the pedal deeper. The car (97 infiniti i30) jerked badly, made a noise, felt like a ran over a curb going 25mph! After that the car shifted perfectly going from speeds of 0-55 mph in all different types of acceleration. Called my mechanic and he said my tranny mount rubber might be busted and the loud jerk/noise was metal-on-metal since the rubber is probably gone.

Could something be wrong with my tranny? I had it serviced (power flush, new fluid, etc) about 1 month ago.

How hard is it to check/replace "tranny mount rubber"?

 

[HappyPuppy]

Why don't you jack the car up, crawl under it and take a look? Only you can decide whether or not your have the mechanical skills to change a tranny mount.


EDIT, EDIT, EDIT: After jacking the car up place jackstands under it before crawling underneath. I wouldn't want you to get squished because your cheapass jack failed and dropped the car on your noggin. :Q

 

[ElFenix]

Originally posted by: HappyPuppy
Why don't you jack the car up, crawl under it and take a look? Only you can decide whether or not your have the mechanical skills to change a tranny mount.

jack?

 

[v3rrv3]

If it's where it mounts it'd be something I'd probably rather have my mechanic due. Sounds like a pain in the ass to me.

 

[ElFenix]

Originally posted by: v3rrv3
If it's where it mounts it'd be something I'd probably rather have my mechanic due. Sounds like a pain in the ass to me.

yeah, getting mounted by a tranny sounds like a pain in the ass to me too

 

[HappyPuppy]

Originally posted by: ElFenix

Originally posted by: HappyPuppy
Why don't you jack the car up, crawl under it and take a look? Only you can decide whether or not your have the mechanical skills to change a tranny mount.

jack?

Yes, Elfenix, jack. I understand that most of the pimple farmers around here don't understand the word unless the word "off" is connected to it, but hope springs eternal from my bosom.

 

Red, before you do anything else, with the key removed from the ignition, disconnect the negative battery terminal for twenty minutes, reconnect and then drive the vehicle normally until it is fully warmed up, this will erase the memory of the E.C.M. and P.C.M. and allow them to relearn the operating characteristics.

If the problem continues, pm me.

 

[Scarpozzi]

You should be able to spot the mounts pretty easily. I'm guessing it's front wheel drive so you can probably jump under the engine and look for where the tranny bolts on and see if anything looks out of place. When your transmission shifts, the whole engine may sometimes move on the mounts a little... I had a car that had a busted mount for a long time and it never affected anything that I could see. (though the tranny went out at 140k)

 

[HappyPuppy]

Originally posted by: Roger
Red, before you do anything else, with the key removed from the ignition, disconnect the negative battery terminal for twenty minutes, reconnect and then drive the vehicle normally until it is fully warmed up, this will erase the memory of the E.C.M. and P.C.M. and allow them to relearn the operating characteristics.

If the problem continues, pm me.

Thank you, Roger, for saving the young man from a fate worse than death. Being squashed by a falling vehicle is tantamount to ..... er getting killed.

 

[Goosemaster]

Originally posted by: ElFenix

Originally posted by: v3rrv3
If it's where it mounts it'd be something I'd probably rather have my mechanic due. Sounds like a pain in the ass to me.

yeah, getting mounted by a tranny sounds like a pain in the ass to me too

lol +5 funny

 

[Quixfire]

Hey Red, did you get you car fixed?

 

[Red]

Roger and Quix, you have PMs. (Car jerked again last night when I floored it merging onto the Interstate to avoid a truck hitting me ITB).

 

[Quixfire]

Hello Red,
I have searched every database I could get into and cannot find a service bulletin or post about your concern. My best guess would be a transmission sensor or downshift cable failure or a faulty Throttle position Sensor. The downshift cable could prolong a shift causing it to bang/jerk when it finally engages or a TPS could given the PCM the wrong reading causing the engine to jerk when it compensates for this misinformation.

I would recommend contacting the dealer to see if this is a know issue before trying to service it yourself.

 

[pmoa]

Originally posted by: Red
Roger and Quix, you have PMs. (Car jerked again last night when I floored it merging onto the Interstate to avoid a truck hitting me ITB).

maybe you should just ride the bus