I got the car back from the shop today. He replaced both axles once again under their lifetime warranty on the off chance the first set might have been bad.
I will have to admit that its working much better than before...the 40-50 mph vibration is now very slight and heavy throttle still makes enough shake to "buzz" things inside the car. I made one full throttle blast and got a nasty rattle right before shift point.
In a last effort I'm gonna try rotating my dogbone mounts 90degrees...if this helps I may go with a set of poly mounts to replace the stock (obviously shot) rubber mounts.
If this doesnt do the trick then that only leaves tranny problems and I dont even want to think about that right now. Especially since I dont race the car or do burnouts. The fluid and filter have been changed twice since I've owned the car. If this is the best tranny life GM can offer then this will be my last GM car. My wife is right, I do love the car but its stabbing me hard and not making life fun. Here's hoping the dogbones do the trick and life gets good again...if not I may give up and cut my losses.

Good luck with it t-bat.

Im sure that youve already checked, but do i remember you trying the lower motor mount? or the tranny mount?

this is sad to read, very sad, i'll pour amillion bux into my GTP before I part with it, its the best car ive owned

best of luck to you my friend!!

Hey Tbat Chrysler hasn't had the best luck with tranny's either

Remember the top mounts have 2 parts and the round bushing (closest to the engine) is often overlooked,I did notice a much firmer feel whrn I went to billet dog bones with poly bushings,also I am building a tourqe arm much like thrashers unit that welds from the LCA to frame because I do have wicked tq steer at shifts ,the point is I could fab you up a set if you have someone to weld them on I should have one set built this wkend they may be worth a try ,sorry to hi-jack your post but it's too bad your so far away I'm sure your problem can be solved and I'm sure you're frustrated by now ,this is one of the problems of FWD as they get a little older ,anyway if I can help let me know.Chico(pops)

Yep, both of those have been replaced...just two in a long line of "I hope this fixes it" parts...but thanks for asking.

No sweat on hijacking the thread Pops, if anyone has experience here its you. I admire the fact that you have repaired and replaced so many things on your ride without ever expressing any frustration here on the board.
I guess I need to stop using my old Intrepid as the yardstick by which other cars will be judged...I'll probably never have another car that good.
I suppose its also a good thing that the Denali XT is strictly a concept cuz if that badboy was on the showroom dressed in black it could spell a quick death for the T-Bat. I know I swore off buying new cars some time ago but that one has my eye. I'm sure my wife would have other ideas.

Hey TBat, asking around I learned the bolts on the converter loosen up, and fly wheel bolt problems... don't know how true but.... check motor mounts,rotors, and wheel balance. Good luck.

He checked the rotors for true and even swapped wheel/tire package.

Tbat it's funny you use an Intrepid as a yard stick. Everyone else I've known they drove em crazy. One was even officially labled a lemon by CA law and Dodge had to buy the car back for the original sale price plus out of pocket expenses such as towing and such.

There are things about the GP that drive me crazy quality wise like the windows, AC compressor clutches, squeaks, weather stripping that looks like it's been on the car since 1968 and other various little things I've had to fix/replace but I've yet to see a car styling that moves me as much as the 97-03s. So I'm able to overlook all it's flaws. Not many DD 10 year old cars do that to me.

1999 concorde, oil light on motor puked. Chrysler missed the boat on their 6 cyl motors oil galleys too small, with sludge build up you were dead in the water. Had one, car not worth fixing. Now it's probably a rice rocket or ash tray.

my Trep was a 95 with the 3.3 pushrod engine...the 98-02 (2nd gen) had many engine issues with the north/south 2.7 ...the 3.2 and the 3.5 were much better engines all around...but the 1st gen car with the 3.3 was reliable as a rock...there were some tranny issues with people mixing fluid since this was their introduction of the ATF+4...many owners mistakenly poured dexron or typeF into their trans much to their dismay later. After 02 many improvements were made to the 2.7 just in time for the LH platform to be axed in favor of the new LX (300/Magnum/ Charger)

I do agree Herc that the GP has many pluses...prolly the only reason the car has lasted with me for this long:)

hey i got dibs on the rims and tires.....lol


dibs..lol

What is a dip? This isn't skoal.

i think bobby is the first for the rims...

but besides the point we are a family we should be encouraging tim to keep the gp, not let it win and feed the vultures haha

i wish gp parts were as cheap as skoal haha

but we are hungery

T-Bat I think its time to get a G8

SUCCESS AT LAST!!!

Someone once said that football is a game of inches. I submit to you that man never owned a Grand Prix.
I had a spare set of mounts that I had gotten from Ed some time back with the intent of powdercoating ot chrome plating them. I anchored them to the workbench and used the WD-40/two large screwdrivers and a box end wrench to rotate the dogbone inserts 90 degrees. this took all of 15-20 minutes and then another 15 or so to install on the car. I had just finished swapping the 18s back onto the car (at my wifes behest) and I went for a short test drive.

What a difference an inch can make...the 40-50mph vibration is history and the throttle-on steering wheel shake is gone as well. full throttle blasts onto the interstate are pointed by crisp shifts and my K&N heat shield no longer rattles against my hood. There is some slight vibration transmitted from the engine, the kind of which I assume would come from poly mounts. You can feel the engine pulling in the seat of your pants and thats the kind of feeling I can happily live with.
I let it rip on the interstate on the way to work, up to about 85mph and then back down to a 70mph cruise...aside from the tire roar, it was the kind of ride I remember this car being capable of, so once I swap to a more compliant wheel/tire combo the car should be ready for hi-way duty once again.

All this felt so good I swapped in my tinted tail lights. I'll post thread with pics on that tonite when I get home from work.

My thanks and gratitude to you here one and all...for your support both technical and emotional. For any faults this car may have, the support of fellow enthusiasts like yourselves makes up for a lot.
It feels very good to feel good about my car once again.

Good for you TBat, I hope I have the patience a lot of you guys have. I've only had this car 3 1/2 weeks and already have motor problems. We shall see. Good luck with your "new ride".....

YAY!!!!!!! your keeping your Bad Ass gp. looken good now driven good way togo

So I thought you only wanted to get ride of wheels/tires cause of vibration, you still getting rid of them?
I am glad you figured it out. A whole inch huh, that's not what she said!

WOW! Well, I dont think you have to worry about anything breaking in the front anymore now that its all been replaced!

looks like your set for another 10 year run. way to go batman you saved the day yet again. i think you just swaped the rims just to have a reason to see them on the montanna.

the rim swap was an experiment (but it was funny seeing my wifes reaction)...I will still be selling the 18s at somepoint in the near future in favor of some better riding wheel/tire combo...I think I will be leaning back towards the stealth look...just havent decided yet...style and money are always balancing factors.

i wouldnt mind the rims but i think bobbys in line first

Glad to hear you've got it fixed, and the Tbat is prowlin' the streets once again!

Sweet!!!! Glad something finally worked and it wasn't tranny related. I told ya the rotation would be easy.

You should buy my wheels!

Ahhhh another reason to stay stock on ride hight and wheel size

I tell my wife constantly "I can feel myself slipping into old guy mode...more subdued exhaust, softer ride and generally less willing to mod heavily. I gotta say I admire Chico for being the hardcore mold breaker but I'm just not so willing to make those trade-offs anymore.
I may very well have brought some of these headaches on myself but thats life, and Lord knows I've learned from it....

But I'm sure I wont stay stock on wheel size

I'm glad you found the issue. It's amazing how small the culprit was (and how easy it was to fix).

Get rid of the bullits for some mag wheels. I want to see some 15s with big meat on them. If it looks good (like your sig) I might have to copy it one day.

I'm still considering the 17in Bullitts and keeping my center spinners, but I would like those to be black. I suppose I could paint some gray/silver ones since there are good deals out there on those. The real bummer is if you want raised white letters they pretty much come only on 15in tires. Goodyear offers the NASACAR Eagles but they are pricey tires. Other than those you can pretty well forget white letters on 16/17 and up.
The 245/60/15 is within 1mm of the stock tire diameter...so there are a few factors to consider.

I think my tires were 100 bucks a pop. They were comparable to all the other decent wet/snow traction tires available in the stock size.

you grabbed a good deal...tire rack gets $118 and bigwheels.net gets $133...plus they only come in 225/60/16.

I got em online some where I forget where but I got ripped on the mount and balance. All four ran me about $100 to mount and balance I won't be buying tires online anymore. I thought I was gonna save money but it seems for most places (99%)if you don't buy the tires from them they gouge you on the mount and balance That was in Maine not sure how it is here in Marietta. And barring in blowouts I shouldn't need new tires while I'm here.

Glad to hear that you got it fixed. Now I just gotta figure out what mine is doing one day when I have time.

Thats awesome t-bat!

Congrats!