Chrysler 300 Transmission Shuddering

Maintenance/Repairs
1

My wife and I purchased our 2005 Chrysler 300 Limited in May 2004.
Our 300 has over 117,00 miles as of May 2011. It has been a rather dependable automobile.
I have enjoyed it almost as much as my HD. We have performed maintenance as close to the schedule as possible.

I failed to drive the car as often as our second car is an used 2002 S430 which had been my primary auto until about two months. My niece and nephew reported to my wife that the car was not “doing something right”. No one could really explain, so I had drove the vehicle myself to determine the issue. The transmission had the feel that it was being “slammed” into the next gear without any clutch. Once the car was warmed up, it appeared that when it shifted at 38-40 mph or 48-50 mph, the car shudders. It almost resembles the feeling you get when you run a car across those strips in the road.

I took the car to the dealership where I have had it serviced locally. They replaced a module which had Technical Service Bulletin from Chrysler for noted similar problems. The first module replaced did not resolve the problem. I took it back and they tried again with the end result being same as before I took the 300 into the shop, transmission appeared to shudder when shifting at the midrange gears.

The dealership as another option recommended that the transmission be replaced. I was not confident with their assessment as I had the distinct feeling they were not clear on the real issue.

I took the car to another service shop which I had more confidence in their work. I asked that they check the car for the problem with the transmission as I wanted their assessment. At this point, I had pretty much decided that I would get rid of the car, but did not want to give anybody else the troubled vehicle nor did I want to have to rush to decide on an automobile to purchase.

The second shop recommended the transmission be replaced, as well several other items be checked as there appeared to be oil leaks. The CAM plugs had been replaced as part of the service the dealer performed though the engine area had not been cleaned of the previous oil. That news was alarming, as the price estimate for a replacement engine was around 6500-7000 smackeroos, way outside of my comfort for repair on the car.

I was able to locate a used transmission with only 86k on it through a very gratuitous turn of fate. I digress, however, as the source for the used transmission was available only to licensed shops.

Two shops had referenced a transmission repair shop as one of the best in our small county. I left the car with the transmission shop for their testing, and it came back with their recommendation that the problem existed in either the coil or spark or an area related there.

I again took the car to the second shop and asked that they check the engine thoroughly for any issues with the spark plugs, wires or similarly related issues. The shop reported that the motor compression was at 190 across all six cylinder and the spark plugs and wires were new and there were no issues with the coils.

I am most happy that the engine is in excellent condition. I have planned to take the car back to the tranny shop as I reported the findings to him of the other shop. I am concerned about the transmission, though I am driving it about 60 miles round trip to work about 2-3 days each week. It still convulses at the mid-range shifting but otherwise runs pretty good after that. The car body is in very good shape as is the interior.

I was reluctant to trade or sell the car with the problem noted as I hate to leave someone with the problem. Have you ever encountered anything similar on the Chrysler’s you’ve experienced? What resolved the issue? I can imagine getting a new car in a few months. I just hate having to run out and spend money on cars until I really have one that catches my full attention and desire.

Thanks
Ronald
Salinas, California

2

Was the transmission fluid recently changed? If so, and genuine ATF+4 fluid was not used, this could be the problem. These transmissions are very picky about the fluid used. A generic fluid with a “friction modifier” won’t cut it.

It is unlikely that unless this engine has been really neglected in terms of oil changes, that there’s anything seriously wrong with it. The 3.5L engines are pretty solid and reliable.

If you take the car to a good independent shop (not a Cottman or AAMCO), they should be able to put a specialized scan tool on the transmission and determine whether an internal problem exists, and how much clutch material is left, among other things.

I’m not sure what generation transmission is in this vehicle, but this model of transmission was a problem area in cars with this powertrain. I think by 2005, that you would have the upgraded version with beefier parts, that is not as susceptible to early failure, but if the fluid and filter haven’t been regularly changed, it’s possible. I have an older car with the same powertrain, and the engine is still going strong at over 250K, with the transmission having been rebuilt once at 135K.

These aren’t the quickest cars by todays’ standards, nor quite as luxurious as your Merc no doubt, but you will miss yours if you get rid of it. They definitely drive nice and have character, and you’ll be hard pressed to find a more comfortable car for long trips. A transmission diagnostic by a good shop is essential. If it turns out that you need to replace the tranny, the used one sounds like a good deal, as long as you get some warranty with it. Good luck.

3

A rumble strip feeling is often caused by aged or incorrect transmission fluid. That’s not to say that the fluid is definitely the cause of this problem but there is at least a strong possibility that it could be.
If the car were mine and no serious codes show up on a scan I’d change the trans fluid and go from there with possibly adding a can of Berryman B-12 to the trans fluid as a bonus extra.
I’m kind of surprised none of the shops have mentioned this.

The engine compression readings are excellent and I can assure you that the current 190 PSI readings are the same as they were the day the car rolled off the assembly line new.