Hello, my problem is that my automatic transmission has a shake when it shifts to first gear. For example: I am currently driving in 3rd gear then I hit the brake. When it reaches the first gear, I feel a bump like if I ran into a small hole. I’m having this problem for about 3 weeks and it only happens when it reaches first gear. I Want to hear your opinion before taking it to a shop.
That's called "bump shift". In some cases installing new software into the transmission computer will solve it, but sometimes you just have to live with it. My '93 Dynasty has done that all of its 4,100 miles and reflashing the software didn't change anything.
December, 6, 2010 AT 1:01 AM
My 02 did that it also bumped when shifting into the kickdown gear at highway speeds I've had the computer reprograms twice for the transmission and it works fine after that. The shop I took it to only charged 25.00
December, 6, 2010 AT 1:28 AM
Thanks for the info. There's actually a list of about a dozen common complaints that reflashing is supposed to address, but most of the time it doesn't make any difference because the electronic automatic transmission controller (EATX) constantly updates the shift schedules to make up for clutch pack wear and driving habits. Reflashing just sets a new starting point from where it will gradually start to update again.
You're also referring to a different problem. Miguel01's problem occurs when approaching 0 mph. The downshift to first gear occurs late and feels the same as when the transmission is shifted into gear when standing still. That's called "bump shift" and there really isn't much that can be done about it. What you're feeling at highway speed is something different that reflashing obviously helped.
Bump shift can be really annoying when you do a rolling stop where you accelerate away without coming to a complete stop. The downshift occurs just as you hit the gas and makes a really noticeable jolt. I can still feel it in my Dynasty even though I baby it.
December, 6, 2010 AT 1:54 AM
Caradiodoc you know exactly the problem I m having. I am experiencing the same problems you are with your Dynasty. There is something I didn t add to the question. Everything started when I notice a leak from the transmission. I immediately took my van to a mechanic shop because I knew these vehicles have a bad reputation when it comes to transmission.
The mechanic told me that the leak was coming from the transmission pan and it needed to be replaced. Here in New York City it cost me $60.00 for the service.
After this, I started feeling the bumpshifts. I went back to the shop and the mechanic ignores me saying the van already had that problem when I took it there. You guys have any suggestions?
December, 6, 2010 AT 2:10 AM
60 bucks to reseal a leaking pan is not bad considering the time to clean it up and the new fluid that's needed. If they put in the wrong type of fluid, it can cause some strange sensations but it shouldn't hurt the transmission. The next time it is due for a filter and fluid change, the right fluid will be in it.
Also, if the problem doesn't improve on its own, you might consider having the dealer reflash the transmission computer as hahny1 suggested. That involves installing new software and the dealer will have the latest updates. Chrysler and Toyota are very good about making the reflashing available to the independent repair shops but they don't do it very often so they might overlook something. Sometimes these problems develop due to wear taking place inside the transmission or there could be a bug in the software. Either way, it is not uncommon with today's vehicles to need to update software once in a while.