You have to tell them the PCM makes assumptions based on the final drive ratio, and if it'* wrong, shift tables will be wrong.

Alright. I can take him for a ride too. I know all the tricks to make it shift like crap, thanks to everyday driving. I can make the TC shudder reallll bad if I'm real light on the throttle on the way to tc lock, and when it locks at 45, you'll swear a chunk of steel just fell off something in the drivetrain lol. And then as long as it'* locked and you apply throttle, it just keeps shuddering until you tap brake and lock it normally. It'* real goofy...

When the shift tables in the PCM are wrong because the gear ratio in the trans is wrong, performance AND fuel efficiency are both hurt.

I gaurantee you that if you get an attorney, you'll win. This is black and white.

Well, you didn't necessarily get an "inferior" transmission, just the wrong transmission.

I'd be willing to bet the shop didn't know the difference. Doesn't mean they'll be happy to have the difference explained to them, of course...

Well I called the dealer, then the warranty guys. The only guy that could understand what I was trying to say was the guy in the service dept at the dealership. I kept confusing the people at the warranty place, and the one lady got pissed off at me for confusing her with all the numbers. I was like well I don't know how I'm supposed to get service if the claims respresentative doesn't understand the situation lol. So she talked to the guy that handled my claim, he recommended me dropping the car off at the transmission shop and letting them start the claim. I'm going to have to walk them through it, I can feel it now...

Going to drop my car off at the dealership and pick up the rental Wednesday next week. I wanted to avoid all the holiday hub bub.

I'll keep you posted...

Alright. I've taken the time to type up a somewhat detailed letter to explain to the transmission shop what exactly is going on here. I'm going to go ahead and post it, and let you guys take a look at it to catch anything I may not be catching. I will be getting up around 9 am tomorrow morning to drop it off and pick up my rental.

Joshua Lowe
1997 Pontiac Bonneville SLE


Dear CAT,

This is the third transmission this vehicle has had in my ownership. The first transmission was taken out when the car was first purchased through the warranty. It had a habit of downshifting into neutral when throttle was applied from 25-35 MPH. The second transmission only lasted a few weeks, and tended to shift very rough. When you guys pulled that one out, you said the torque converter was making metal shavings.

The third transmission, which is the one that is currently in the vehicle, has been acting somewhat strange. I eventually just assumed I was being too much of a perfectionist. The time to shift from R to D is much greater than the first two transmissions. Also, on certain days, the 2-3 gear shift can be very delayed as well. The most noticeable issue with this transmission is whenever the torque convert is locked and the car shifts into 4th gear @ 45MPH, the shift can be very rough and unsteady. You can feel the engine and transmission rock when it shifts. It typically happens when you’re slowly approaching 45 mph in traffic, or a similar situation. Once the TC has locked and it’* in 4th gear, it takes at least half throttle at most times to get the TC to unlock. If you try to put a load on the transmission (i.e. going up hill, accelerating) while the TC is locked in 4th gear, the transmission tends to shudder. I know it’* not in the engine because I’ve tested/replaced everything associated to that type of symptom. I’ve tested the ignition coils, replaced spark plugs, replaced wires, inspected o2 sensors, cleaned MAF sensor, and cleaned the throttle body to no avail or improvement. The dipstick also shows signs that the transmission may be producing metal shavings, as there are typically a metallic grey residue on the rag when it is wiped.

I have also noticed that the dogbone mount has deteriorated to the point where it will need replaced. I’m not sure if it was during one of the transmission installations, or if it’* because there’* what appears to be transmission fluid leaking on it from somewhere above it. I have purchased a new dogbone mount, and it is in the passenger seat. If possible, I would like you to replace the mount when the transmission is replaced once again. Please make sure no transmission fluid is dripping on the new mount once it is replaced.

Finally, after some intensive study and research, I have discovered that this transmission is not meant for the PCM on this vehicle, and is not the same type of transmission this vehicle had straight from the production line. The transmission that has been installed in this vehicle, as identified by the “7ASW” tag on the transmission, is described as 1997 C/H-Body 4T60E with 2.86 gears and 1420 stall torque converter. The transmission originally equipped for this vehicle, as determined by the “FW2” in the RPO tag in the trunk (picture attached on page 2), is described as 1997 C/H-Body 4T60E with 3.06 gears and 1897 stall torque converter. The transmission tag should state “7ACW”. I have also attached the transaxle ID chart.
[end page 1]
[begin page 2]
If the PCM is running the 7ASW transmission with the shift tables of the 7ACW transmission, that would explain the erratic shifting and poor shifting performance. Also, since this transmission has been installed, I’ve noticed a significant loss in gas mileage and performance. I’ve contacted Guardian Warranty Company and they’ve suggested that I bring the car to the transmission shop for you to confirm this. Guardian Warranty Company’* phone number is 1-800-xxx-xxxx.

It would be much appreciated if you could please contact the warranty company and explain to them, in a brief summary, everything that I’ve stated in this letter.


Thank you,
Joshua Lowe

[Insert Picture of RPO Label here]

[end page 2]
[Page 3 is 1997-99 4T60-E ID Chart]

VERY well done. If they say 'take a hike', you have a rock-solid letter for an attorney. And the trans shop will know it when they read it.

Awesome, thanks for the approval. I'll go ahead and print that out now. I'll let you guys know how it goes.

good luck with this... i expect them to be a PITA at first, but when they realize they screwed up and that there is the possibility of legal action, they will most likely be very accommodating

Ok I'm just throwing this out there, what is the possibility of getting a computer to match the transmission that is in the car now?
I know that isn't what the desired end product is in this car, but is that even possible to do?