AOD transmission shutter/vibration

mode101

Member
Apr 13, 2003
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Dallas, TX
My 02 is having a really weird tranny problem, which I will try to describe.

Starting off easy from a stop light, I will accelerate to about 35-40. When I get to around 40, and the tranny shifts up to a higher gear, the tranny will start to shutter shake and vibrate (the whole car) as it goes into gear. While driving at that speed, if I want to accelerate and give it a little gas, it will do the same thing only worse - more shakes and vibration as it drops into a lower gear. It seems to do it worse when the tranny has warmed up. It will also do it on the highway at passing speeds. As the transmission is going into the highest gear, it will do it. It does it on the last shift of an acceleration as it goes into the cruising gear.

It just started doing this about a month or two ago. At first it was only doing it every now and then, now it does it all the time, and its getting worse. Automatic 02 GT vert. 42k on the clock. Car runs perfect otherwise.

Can anyone please shed some light on this.
 
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there is several different things this can be.. it can either be a engine driveability concern or it could be a trans problem.

many times a shuddering concern in high gears whne the tourqe converter is locked is a engine misfire. the engine is under more load durrng light acceleration with the converter locked, anytime you have low rpm's and high load that can cause secondary ignition related misfires to be easier to notice. If this is your problem then it could be as simple as spark plugs.

If it's in the transmission it could be many things, a internal leak that causes a presure loss such as a cracked piston cup could also be converter chatter. To be honest I would need to drive the car to get a better idea of what is going on.
 
Service

I bought the car used, with about 25k on the clock, it has around 42k now. I have done basic maintenance. Oil changes (m1 5w20) every 3k, I have changed the coolant once.

I have not had the tranny fluid flushed and filter changed yet. I did not know if it would help since the problem came on so suddenly. I was actually holding off on changing it since I was going to take it in, I didnt want to just waste that money. I fugured they probably would have to change the tranny fluid if they service it anyway.

It is gradually getting worse. Today a new noise, from a stop it made like a squeel type noise, which kind of sounded like a clutch slipping.

:shrug:
 
The only way all the tranny fluid will be changed when they work on the trans is if they rebuild it, or sell you a trans flush.

you may want to try a trans flush. look for a place that offers a bg trans flush and will let you watch them do it. We have this machine at my work and I have cleared up a few problems like this with the flush.. JUST MAKE SURE YOU CAN WATCH THEM DO THE FLUSH..

MANY MANY techs don't do the flush and just say they did it. or they change the fluid but don;t run the chemicals through the trans first. You have to make sure they add the cleaner then drive the car through all the gears either on the road or on the lift.. If this is not done then it will be a waste of your money.

Do not trust any shop I don't car how well you think you know them.
 
Installing an good plate style external transmission cooler along with the flush/fluid change is a great way to cure the dreaded torque converter shudder as well. Superheating the fluid in stop and go traffic is a sure fire way to degrade it in a hurry and is often what causes this. If it was an earlier mode (pre-99) 4R70W, there are a host of late model upgrades you can do to cure it, but since it's a late model trans, the tranny cooler would be my first move. I think installing one should be a manditory modification anyway, whether your'e having problems or not.
 
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I have the 4R70W in my 95 GT. I just replace the shifter control solenoids and after running all the gears I start driving and once the engine heats up it starts to shake when shifting gears what do you suggest