Weird feeling in pedals [Archive] - GrandAmGT.com Forum

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GrandAmMe
04-26-2012, 08:01 PM
Just picked up another GAGT. One owner, 143,000kms, super clean etc...

Previous owner just had the main seal on the crank replaced cause it was slowly leaking. \

Only issue remaining is the strangest feeling in the pedals. Its only in drive. It feels like meal on metal grinding. Only the feeling....not the sound. It's only there when there is a load on the engine in drive. It goes away as you get up to coasting speed.

My Body shop guy said it seems like the rear motor/tranny mount. This would make sense since it does not happen in reverse and only happens when the engine is under load in drive and goes away as you coast. Its nothing to do with the brakes, cv shafts etc..cause it is only under engine load, not all the time when the car is moving.

The engine does rock back and forth quite a bit but not too bad. I agree with him somewhat since the engines vibrations are being transmitted through metal on metal contact due to worn out rubber on the rear mount. Only goes away in reverse or in park revving because the engine torques towards the front of the car whereas in drive the engine moves towards the firewall.

Not thinking its a transmission problem since it completely disappears if I let up on the gas in any gear and also disappears once i get to coasting speed. This is driving me insane.

What do you guys think?

Here is a video of the problem, mostly a description. You can actually hear it come and disappear at 1:02 (Disregard the exhaust leak comment)

http://www.youtube.com/watch?v=lsgeiM9e25s

locoman99
04-26-2012, 08:07 PM
Pop your hood and stand beside the car while someone else sets the e brake, puts the car in drive and gives it some throttle. If your mount is shot it will be obvious by how much the engine bucks.

GrandAmMe
04-26-2012, 08:25 PM
Pop your hood and stand beside the car while someone else sets the e brake, puts the car in drive and gives it some throttle. If your mount is shot it will be obvious by how much the engine bucks.

I did this a few times. It shakes quite a bit but nothing too serious. The more and more I think about it the more and more it puzzles me.